(UNTITLED)

• Document Type: CREST
• Collection: General CIA Records
• Document Number (FOIA) /ESDN (CREST): CIA-RDP83-00423R001900030002-6
• Release Decision: RIPPUB
• Original Classification: K
• Document Page Count: 45
• Document Creation Date: December 14, 2016
• Document Release Date: October 29, 1998
• Sequence Number: 2
• Content Type: PHOTO

Approved For Release 2001/03/06 : CIA-RDP83-00423R001900030002-6
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Approved For Release 2001/03/06 : CIA-RDP83-00423R001900030002-6
Approved For Release 2001/03/06 : CIA-RDP83-00423R001900030002-6
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Approved For Release 2001/03/06 : CIA-RDP83-00423R001900030002-6
Approved For Release 2001/03/06 : CIA-RDP83-00423R001900030002-6
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Approved For Release 2001/03/06 . CIA-RDP83-0
Efficiency .
Operating and Maintenance Eamon'
Overload Capacity . . .
tgatig. 0 '_,"Arpl:a0"'Probleffl
Photo-Review of Typical Installations .
'pie tit the loitroit Rectifier
nstruction of the ignitron Rectifier 22
Auxiliaries of the Ignitron Rectifier . 28
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ANOTHER PRODUCT OF WESTINGHOUSE
RESEARCH SPEEDS INDUSTRIAL PROGRESS
From the original idea to the installed and working
unit, the IGNITRON RECTIFIER is a product of West-
inghouse research. It is another?and important?link
in the long chain of Westinghouse developments in
the field of generation, transmission and conversion
of electrical power. Westinghouse research in these
fields has been continuous for more than a half cen-
tury. Ignitron is exclusively a Westinghouse contri-
bution to the progress of modern industry.
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120,000-ampere, 673-volt Ignitron Rectifier
installation for electrochemical service.
4 1000 kw, 600-volt Ignitron Rectifier fo
transit service.
1000 kw, 250-volt Ignitron Rectifier for steel
mill service.
750 kw, 250-volt Ignitron Rectifier for steel
mill service,
IGNITRON RECTIFIERS introduce a basically new
principle in the utilization of the rectifying property
of the mercury vapor arc, which greatly increases the
efficiency of power conversion in the 250-3000-volt
range. Under this new principle it is possible to de-
sign a rectifier which more nearly approaches the
theoretical efficiency of the mercury arc.
Improved efficiency and added economy, maximum
availability and long-time dependability are designed
into the Ignitron Rectifier. Not only is the scope of
mercury arc rectifiers extended to include the lower
voltage range, but new high standards of perform-
ance are attained as a result of the basic improvement
in design and operating principle.
The original cost of Ignitron power conversion equip-
ment compares favorably with that of rotating types.
Real savings are to be had in instal-
lation, operation, and maintenance.
An investment in Ignitron Rectifiers
becomes increasingly profitable.
\kali
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\./
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HIGH EFFICIEN
The fundamental method of operation
of the Ignitron with its intermittent ex-
citation system and individual tubes
for the anode and cathode is responsi-
ble for the high efficiency. By the re-
duction in shields and arc length, the
Ignitron reduces arc drop and pro-
vides increased efficiency. The curves
here show the efficiency advantage of
the Ignitron over synchronous con-
verters and motor-generator sets.
HIGH EFFICIENCY m
Uniformly high efficiency over the
entire load range is a characteristic
of the Ignitron Rectifier which offers
decided advantages in many applica-
tions. For constant 24-hour loads the
higher efficiency of the Ignitron Rec-
tifier is of great importance. For highly
fluctuating loads Ignitron Rectifiers
contribute to economy of operation by
maintaining their high efficiency
under light load conditions.
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LOW 4hzae, COSTS
Low arc-drop loss and resulting high efficiency
. . . simplified, automatic operation. . . freedom
from problems of high starting demand, syn-
chronization and reverse current . . . these
factors contribute directly to greater operating
economy in Ignitron Rectifiers. In contrast to
rotating equipment, Ignitron Rectifiers require
no special air cleaning or ventilating service.
LOW
They do not require bearing or commutator
maintenance. Regulation and control are sim-
ple, and for the most part automatic. Near-100%
availability of power when needed likewise
contributes to operating economy, by avoiding
costs incidental to delays and stoppages. An
Ignitron Rectifier is always ready to deliver
power instantly, at any load demand.
Many features and characteristics inherent in
the simplified principle of operation of the
Ignitron Rectifier provide reduced maintenance
costs. These include:
1. Absence of commutators, brushes, collector
rings or bearings which require periodic
maintenance and replacement.
COSTS
2. Absence of windings subject to deterioration.
3. Operation of interior parts in a near perfect
vacuum.
4. No parts requiring periodic replacement.
5. Cooling system protected against corrosion.
Ignition tube showing copper cooling coils. Finished Ignition tube with cover over coils.
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41 cie
OVERLOAD CAPACITY
Since the only effect of an excessively high cur-
rent in an ignitron Rectifier is the generation
of heat with increased vaporization of mercury,
a momentary overload or even a short circuit
cannot damage the equipment. Provided the
overloads are removed within a reasonable
time, the Ignitron will readily handle applica-
tions involving high load swings. Load shifting
is very seldom necessary. This unusual ability
to handle high overloads for reasonable periods
of time makes the Ignition particularly wel.[
suited to such service as coal mining, street
railway, steel mill and other applications in-
volving overload and short-circuit conditions.
PROBLEM SOLVED
"Arc-back" occurs occasionally in all mercury
arc rectifiers. In the multi.anode tank type, this
tendency can be curbed only by the use of
grids and shields. This solution of the problem,
however, increases arc voltage drop and thus
impairs the rectifier efficiency. In the Ignitron
Rectifier, the arc is extinguished and the source
of ionization eliminated during the half-cycle
when the anode must withstand high reverse
voltage. The distance between anode and
cathode can be decreased, grids and shields
can be reduced. The Ignitron thus offers higher
efficiency with increased reliability.
0
4
30
25
20
15
10
'4'
0
,"
J.:,
,D
0 "t-1?G14 \-010,4
Ck to \VOL
1000 2000 3000
CATHODE CURRENT - AmPERES
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4000
Approved For Release 2001/03/06 : CIA-RDP83-004
VOLTAGE a?Ai
Simple, positive control of the d-c voltage of an
Ignitron is effected by delaying the pickup time in
the cycle of the anodes?which is accomplished
by shifting the ignition impulse. Pickup can be
placed at the exact point in the cycle which will
give the desired voltage reduction. In other words,
the normal direct-current voltage characteristic
of the Ignitron can be reduced as desired by de-
laying the action of the ignitors in starting the arc
to a phase position other than normal. This delay
can be accomplished manually or automatically,
to provide smooth, fast variation in output voltage.
OF INSTALLATION
An Ignitron Rectifier is installed simply by placing
it on a normal strength, reasonably level floor. No
special foundations are required because of its
lightweight construction and vibration-free opera-
tion. Installation consists simply of putting the
unit in place and connecting the control leads,
power leads and water supply. Auxiliary appa-
ratus is mounted in a separate cubicle which is
completely wired. The cubicle is usually mounted
adjacent to the Ignitron assembly, however it may
be located in the switchgear lineup if desired. No
air ducts, ventilation systems or noise suppressors
are required. When installation expense is in-
cluded, the installed cost of the Ignitron is gener-
ally below that of rotating equipment.
Auxiliary control cubicle, which houses the
Ignitron excitation equipment. Open view is
shown above; closed view below.
View showing simplicity of installation.
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Approved For Release 2001/03/06 : CIA-RDP83-00423R001900030002-6
With no rotating or moving parts except
the rotary vacuum pump and the centrifu-
gal water-circulating pump, the Ignitron
Rectifier is remarkably quiet in operation.
Where substations must be maintained in
office buildings or residential districts, this
quiet operation is a very real advantage
that means much in good will.
Skid-mounted Ignitron Rectifier designed for ease ir:
changing substation locations.
LIGHTWEIGHT ? COMPACT ? PORTABLE
Though sturdy in construction, the Ignitron
Rectifier is lightweight and compact. Com-
plete rectifier and associated apparatus
can be mounted on skids for portability,
and the entire power conversion unit then
load center changes. The compactness of
the Ignitron in relation to its rating is a
decided advantage where space is at a
premium. In cases where existing stations
are already crowded, rectifiers can be in-
can be moved to new locatioas ias. the d--c
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10
Approved For Release 2001/03/06 : CIA-RDP83-00423R001900030002-6
SERVICE RECORDS...ENTHUSIASTIC
ACCEPTANCE...PROVE THE OVER-ALL
ADVANTAGES OF POWER CONVERSION
BY IGNITRON RECTIFIERS
The Ignitron Rectifier was introduced by Westing-
house in 1937, and the first installation was made early
in that year. In less than 12 years, well over 4,000,000
kw of Ignitrons have been purchased. New capacity
is being added at a constantly increasing rate. On the
following pages are illustrated typical installations in
railway, mining, power, general industrial and elec-
trochemical service. Much of the factual data in this
book has been assembled from the
fine performance records of these in-
stallations and the many other West-
inghouse Ignitrons in use today.
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11
Ianitron Rectifiers found quick acceptance in
electric railway service. Of utmost importance,
Ignitron Rectifiers operate at high efficiency
particularly at light loads. They give high over-
load capacity and instant availability.
C1A-RDP83-00423R001900
In addition to high efficiency, and high over-
load capacity, mining service requires installa-
tion in isolated places and low headroom. Being
lightweight, compact, and readily adaptable to
automatic control, Ignitron Rectifiers are par-
ticularly suited to the needs of mining service.
They can be installed in isolated places. 13
led-te 2ool taato6 C1A-RDP83-00423R001900030002-6
14
.Cfeeweer/
zpp.
/torediecoe-
In the electrochemical field, where load is maintained
continuously at full capacity, Ignitron Rectifiers have
undergone possibly the most severe tests that
could be devised for power conversion equip-
ment. Proof that they can carry heavy loads
continuously, with minimum maintenance,
is found in the increasing number of appli-
cations in this field.
15
Industry in general wherever there is need for
power conversion in the range below 3000 volts--
select the Ignitron Rectifier because of its ease of in-
stallation, availability factor, and high overload ca-
pacity. Low operating costs and low maintenance costs
help reduce the total cost of direct-current power.
16
Approved Far Re.
lea
?i
When utilities convert power from a-c to d-c, the cost
per kilowatt of output is reflected directly in operating
profit. As a result, the unparalleled high efficiency
of the Ignitron Rectifier is a factor in the noteworthy
swing to this type of equipment. Momentary over-
loads and short circuits won't damage the West-
inghouse Ignitron Rectifier. Voltage can be
controlled easily and economically.
The Ignitron Rectifier is an ideal conver-
sion device for supplying direct current
for powerhouse auxiliaries. It also has
definite advantages for office building
loads supplied from a d-c network.
17
18
The phenomenon on which the mercury arc
rectifier is based is the :'.act that in an ionized
gas at low pressures, only a small positive
potential with respect to the gas is required to
cause current to flow to an electrode, while a
large negative potential can be applied before
appreciable current flows. The cathode, or
negative terminal, must supply electrons. With
a cathode spot on the negative electrode, in the
presence of a gas an anode will pick up current
when a positive potential is applied. Without a
cathode spot, the negatve electrode will not
supply electrons and no current will flow.
Since a cathode spot cannot be created reliably
in a low-pressure gas by the application of high
voltage, it is necessary to start a rectifier by
some other means. In the multi-anode tank
rectifier, the arc is established by separating
electrodes having an applied potential at the
cathode surface. The cathode spot thus formed
is maintained continuously by a small current
to an auxiliary anode. This arc current main-
tains sufficient ionization for reliable pickup of
the main anodes. The continuous presence of
ionized gas, which includes the time that the
anodes are bearing reverse voltage, greatly
Fig. 1 --Typical efficiency
curi-e for an Ignitron Rectifier
unit.
facilitates the formation of a cathode spot on an
anode, which materializes in a short circuit in
the reverse direction, as an arc-back.
The Ignitron principle provides a method of
starting an arc reliably in a few microseconds.
This method of starting an arc is based on the
fact that when current is passed between a high
resistance and low resistance material in con-
tact, a gradient may be set up at the junction
sufficient to create a cathode spot. This method
is amenable to synchronous application. With
such a system of ignition, the arc may be per-
mitted to extinguish at the end of each con-
ducting period. This leaves the anode sur-
rounded by a de-ionized gas during the time
that it is bearing a reverse voltage. Of course,
in order to take advantage of this method of
operation, each anode with its own cathode is
mounted in a separate chamber, thus removing
it from the influence of other anodes when they
are conducting current. This permits a reduc-
tion of the shields and grids to the rm nimum
necessary to take care of the transition periods
and permits the location of the anode close to
the cathode with a consequently low arc-drop.
Approved For Release 2001/03/06 : CIA-RDP83-00423R001900030002-6
Mercury Vapor Forms Path
for Current Flow
The phenomenon of rectification does not de-
pend on materials of either the gas or the elec-
trode. Mercury, however, is peculiarly suitable
for the negative terminal (cathode) at which the
heat of the arc concentrates on a small spot.
Mercury is a metal which is liquid at ordinary
temperatures, and is vapor at temperatures
which are readily attained and maintained, has
the right density and other characteristics for
both the required conductivity and insulation
strength. The vaporized mercury provides the
path for the flow of current.
This vaporized material is not permanently re-
moved from the cathode surface (ultimately de-
stroying its usefulness) but condenses and flows
back to the cathode as a liquid. Mercury vapor
is a gas in which the collision of electrons with
molecules is highly elastic, and so conducts
current with inherently low loss. The anode or
positive electrode is graphite. Graphite with-
stands the temperatures of operation better
than other available materials, and because
it does not melt but vaporizes directly, it with-
stands "arc-backs" with negligible injury.
Rectifiers must be substantially free from gases
other than mercury vapor. In the common
gases, collisions with electrons are not elastic,
power loss is higher and the breakdown
strength is less reliable. Certain of the gases,
notably oxygen, combine with mercury under
conditions of high temperature and form com-
pounds which would interfere with the ope-a-
tion of the rectifier and in time destroy the
mercury cathode.
An Ignitron Rectifier consists of a gas-tight steel
container in which there is the anode of graph-
ite and cathode of mercury. An ignitor is used
to initiate the cathode spot at each cycle. The
ignitor is a high-resistance rod, partly immersed
in mercury, through which a current of suffi-
cient magnitude flows to the mercury. The po-
tential gradient set up at the junction between
the two materials is sufficient to initiate a cath-
ode spot. The magnitude of the current neces-
sary is dependent upon the resistivity of the
material used for the rod.
Once the cathode spot is started, the anode will
pick up current if it is positive with respect to
the cathode. The arc will be extinguished as the
anode becomes negative, and will not carry
current until the next positive half cycle, when
the cathode spot is re-established by the next
synchronously timed impulse.
FIG. 2--Typical arc-drop curves of 1,500-kw, 600-volt d-c
rectifier units.
How the Ignitron Principle
Reduces "Arc-Back"
It has been found that occasionally a cathode
spot will spontaneously appear on an anode
when it is bearing reverse voltage and when it
should be maintaining its high resistance to re-
verse current. When this happens, a reverse
current will flow. This phenomenon is known
as "arc-back." Once formed, a cathode spot
on the anode will maintain itself as long as
current is conducted to it and the rupturing of
this current requires the opening of protective
circuit breakers.
In the multi-anode tank rectifier in which the
arc is maintained in the chamber continuously,
it is necessary to use grids, shields and baffles
to guard against arc-back. Considerable sep-
aration of the anode and cathode is required
for this, as well as for mechanical reasons. The
shields, grids and electrode separation increase
arc-drop, the amount of increase being pro-
portional to the extent to which arc-back is
minimized. The elimination of the source of
ionization in the Ignitron during the period in
which the anode must withstand high reverse
voltage removes the major condition which is
favorable to arc-back. Elimination of the chief
cause of arc-back makes it possible to reduce
the anode-cathode spacing and the amount of
shielding and gridding. This is done in the
Ignitron with substantial decrease in arc-drop
with a consequent gain in efficiency. Reduction
in arc voltage of the Ignitron from that of the
multi-anode tank rectifier is illustrated in Fig. 2.
The arc-drop is materially less over the entire
load range.
30 al
2
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va.20
1 iht4 01014>N c00
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19 10
000 4000
CATHOD
AAAPPD
Am*
7,r.Assirsr -441000.Av
FIG. 3 ? Wiring diagram of single-phase, full-
wave rectifier.
FIG. 4 -Wiring diagram of Delta three-phase zig-
zag rectifier.
RECTIFIER CIRCUITS
One of the simplest forms of a full-wave rectifier
is shown in Fig. 3. It consists of a single-phase
transformer with a valve element in each leg of
the secondary. The return circuit is connected
to the mid-point of the transformer secondary.
Each of the two valve elements passes current
as it becomes positive, and the result is a pul-
sating current. As the number of phases is in-
creased, the voltage output becomes smoother,
but the time each phase is active is reduced.
The effect of increasing the number of phases
will be seen by comparing Figures 3, 4 and 5.
Obviously, use of more phases decreases the
utilization of the anodes and the windings.
The three-phase connection is a desirable com-
promise between utilization of the phases and
wave form. By special connections of trans-
formers, a larger number of anodes may be
made to operate in groups of three, as shown in
Fig. 6, giving the utilization of three phases and
the wave form of a greater number of phases.
The RMS current in the windings of the two
three-phase d-c windings is only 70.7 per cent
of that obtained in the six-phase transformer.
Excitation Circuit Accurate
and Reliable Ignition
The Ignitron circuit is designed to give a pulse
of current once each cycle through the ignitor
rod to the cathode. One form of excitation cir-
cuit is shown in Fig. 7. The impulsing trans-
former is phased out with respect to the rectifier
transformer so that the excitation impulses have
the correct phase relationship with respect to
the voltage applied to the Egnitron anodes. As
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RECTIFIER TRANSFORMER
PRIMARY
A-C SUPPLY
RECTIFIER TRANSFORMER
SECONDARY
FT
ANODE
IGNITOR
FT
ICATHODE
CY: Y,737,5( 4 7r, 5 :77, 7\ 1 \ /7\ ,
\ ?,/ \ / v
A
A A 1, >' A /5 /
\ /\ / \ \ \ \ \
/ 5 \ 5 / 5 / 5 / \ / \ \
5, 5/ \ \
/5 \ / 5 / 15 \ \
/ \ \ \ / \ \ / \ \\
N/ /?.?
\ \ 5 \ /
CURRENT IN ANODE #1
RECTIFIER TRANSFORMER
PRIMARY
RECTIFIER TRANSFORMER
SECONDARY
-F
11 1-
-Ft
D-C OLIETPUT
ANODE
FTIGNITOR
CATHODE
0-C
\ VOLTAGE
CURRENT IN ANODE #1
voltage from impulsing transformer becomes
positive on its sine wave, current passes through
the linear reactor and charges the condenser.
The reactor governs the charging rate of the
condenser. The same voltage is impressed
across the Hipernik? core, saturable reactor,
pair of rectoxes and ignitor in series. FIipernik
iron has a saturation curve which is a straight
line until saturation is reached, at which point
there is a sharp knee and beyond which there is
practically no increase in flux through the iron.
When saturation is reached, further increases
in voltage will not increase the flux and the
reactance of the reactor becomes very low. This
permits the capacitor to discharge through the
reactor, rectoxes and ignitor in series. The flow
of current from ignitor to the cathode creates
the cathode spot.
The impulses through the ignitors have a sharp
rate of rise which insures accurate and reliable
ignition. Correct timing and energy of the im-
pulse is obtained by correct design of the entire
circuit. Direction of current flow is controlled
by the rectoxes.
FIG. 7--Wiring diagram of Ignitron ignition circuit.
A C SUPPLY
r-i! r--I r-111-1
F-1 F-1
Li I L_.; I I '
_ -
, = I -r-
-41 L 1_1-
SATURABLE REACTOR
?r- _ LINEAR REACTOR
RECTOX
L)-C (../JrFlri
RECTIFIERS it---CAPACITOR
A-C SUPPLY
CHARGING
TRANSFORMER
PRIMARY
CHARGING
TRANSFORMER
Construction Quality Determines Performance Quality
The quality of performance given by a rectifier
is determined by the quality of construction.
By close study of, and adherence to the funda-
mental principles of the mercury arc, together
with the greatest possible refinement in manu-
facturing details, the Westinghouse Ignitron
Rectifier has been brought to a quality that is
unparalleled.
Careful attention has been given in the design
so that parts and surfaces are arranged to pro-
vide the necessary de-ioni zation and gradients
with the least obstruction to the arc, and also
so that the mercury vapor flows from its source
at the cathode to the condensing surfaces with
the least possible turbulence, thus maintaining
the vapor pressure necessary for best operation.
The successful achievement of this objective is
responsible for the high efficiency and freedom
from arc-back in the Ignitron, repeated arc-back
having been the major barrier to application of
mercury arc rectifiers fox nearly thirty years
after the original invention. Random arc-backs
have been brought to a negligible number in
the lgnitron (Fig. 8).
Vacuum-Tight Welded
Steel Ignitron Tanks
Each Ignitron tube or tank is made of specially
selected steel plates, welded vacuum-tight. All
seams are welded on the inside so that no
cracks are exposed where foreign materials
might lodge. Since any extraneous materials
within an Ignitron tube may contribute to the
condition which causes an arc-back, the inside
of each tube must be kept free of foreign ma-
terials, both those which might be left in the
tank when assembling, and by gases that
might leak in du:ring operation.
The design and construction make interior
parts accessible and any one of the Ignitron
tubes of an assembled unit may be serviced
without disturbing the rest of the unit. This is
another factor that contributes to low main-
tenance cost.
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PORCEL
,
INSULA
VACUUM
MANIFOLD
CONNECTION
ASBESTOS
GASKET
TANK
VACUUM
VALVE
ALUMINU
GASKET
or= 000cro
CATHODE
COOLING
COILS
0030002-6
23
SEALS
AL -RINGS
FIG. 9 Cross section show mg metal-to-metal seal.
Seals used by Westinghouse are exclusively of
solid materials, the use of sealing fluids being
avoided completely. The cover plate and igni-
tor entrance seals consist of enameled alumi-
num rings set in a groove of slightly smaller
cross-section diameter and compressed as
shown (Fig. 9). Use of two concentric rings
makes an absolutely tight joint. The enamel is
of a special composition which protects the
aluminum ring from the mercury vapor.
FIG, 10 Vacuum-tight anode bushing.
0423R001900030002-6
Enameled aluminum rings are
set in a groove of slightly
smaller diameter and com-
pressed to form an absolutely
tight seal at cover plate and
ignitor entrance.
Anode leads are taken into the vacuum cham-
ber through porcelain bushings, soldered vac-
uum-tight to the tank with the exclusive West-
inghouse solder-to-porcelain process. Although
this makes a permanently tight seal, it can be
replaced in the field in event of accidental
damage to an anode. Separable joints in the
vacuum pumping system which operate at low
temperatures are gasketed with a speciai grade
of rubber which is substantially free from gas
FIG. 11? Cross section of ignitor entrance assembly.
Exclusive Westinghouse solder-to--porcelain seal applied
to porcelain bushings.
Approved For Release 2001/03/06 : CIA-RDP83-00423R001900030002-6
evolution. The rubber is protected from the
mercury vapor by steel vee-rings which also
constitute a complete retainer for the gasket.
The entrance bushing for the ignitor utilizes a
Kovar-hard glass seal as the vacuum-tight in-
sulator. The entrance bushing for the shield
potential is a special aviation type mica insu-
lated spark plug which screws into the cover
plate and which is made vacuum-tight by a
copper gasket.
Anode Assembly
The design of the anode assembly is simple
and rugged. Electrodes are of highest quality
graphite. Anodes operate at high temperatures
and the anode shank design must provide tem-
perature gradients such that the insulating and
terminal parts operate at permissible tempera-
tures. In the Westinghouse design, these tem-
peratures are maintained by the correct choice
of materials in the anode stem, and with the
aid of a small copper radiator. Use of a water-
filled radiator is avoided. Insulating porcelain
is so located that it operates well within safe
temperature limits.
The anode and shield assembly is shown in
Fig. 8. The shield is made of graphite and is
capable of withstanding the high operating
temperatures safely. Shields are suspended on
Mycalex insulators.
Cathode
The mercury of the cathode is contained in the
bottom of the tank. Cooling fins in the bottom
of the tank (which is covered with external
cooling coils) keep the mercury at correct oper-
ating temperature. The quartz ring confines the
cathode spot to the desirable area and any
accumulated dirt is kept outside the ring, away
from the active area of the cathode. Construc-
tion details are shown in Fig. 8.
Ignitor
An exclusive Westinghouse development, the
ignitor is a pencil-point-shaped rod of high re-
sistivity. It is partly immersed in the mercury
cathode as is shown in Fig. 8. The characteristic
of the ignitor is such that a small impulse of
power initiates a cathode spot. The ignitor as-
sembly includes a flexible diaphragm which
permits adjustment from outside the tank.
Photo shows three stages in the construction of Ignition
Rectifier anode assemblies.
Approved For Release 2001/03/06 : C
Copper coils are soldered to the outside at the vacuum
chamber at each Ignitron tank. Cooling water circulates
through these coils at high velocities. Cooling systems are
made of nonferrous materials throughout.
Efficient, Corrosion-
Resistant Cooling System
It is necessary to provide a cooling system for
rectifiers to dissipate the heat of the arc and to
control the mercury vapor pressure in the vac-
uum chamber. For power units, this is most sim-
ply accomplished by a water cooling system.
Copper coils are soldered to the outside of each
vacuum chamber of the Ignitron assembly, and
water is circulated through these coils at high
velocity by a motor-driven recirculating pump.
In the larger sizes there are several turns of
cooling coil inside each vacum chamber near
the cathode. Use of nonferrous materials for
the cooling system practically eliminates the
corrosion problem, and the use of high velocity
water circulation adds materially to cooling
efficiency. The old-style steel water jackets
were subject to corrosion and the relatively
large water volumes required necessitated slow
Ismer movement with consequent reduction of
cooling effectiveness. If good
quality water, free from acids,
solids and scale-forming mate-
FIG. 12
Ignitron
rials, is available, direct cooling can be used.
Temperature of the recirculated water is main-
tained automatically within permissible limits
by an automatic valve, thermally operated, by
admitting water in proportion to the arc loss.
Water discharged from the cooling system is
maintained at approximately 55" C. On this
basis, an approximation of water consumption
can be arrived at by figuring on 0.3 gallons
of water per minute per hundred am peres of
rectifier load.
lithe quality of the cooling water available is
not high, a water-to-water heat exchanger is
used. The recirculating water system can be
filled with good quality water and
the heat dissipated from this to
the cooling water through the heat
Diagram ot the
cooling system_
-MERCURY
VAPOR
VACUUM
JH PUMP
_
TEMPERATURE i . . ...-_-='-'..:":
7.:`,.,-+V
REGULATOR
k tiVLB III it
0 II
? it 1
\ it 1
It ii
\ ill 1
\
1 FILLING CONNECTION
till
--r--t'
it ,
. II ,
REGULAtOR II I:11 41
4,
.._..7.,?.... 41, _ STRAINER 10 tll
I
g------.L.r44.--4:
AIM CONNECTION cQuNEcricik --, -IF - :: I
" - - xd-, *--1, II
TE/APERATURE
REGULATOR
Approved For Release 2001/03/06 : CIA-RDP83-00423R001900030002-6
exchanger. With this system, the quantity of
water is increased (usually about 25%) de-
pending upon the efficiency of the heat ex-
changer. (Fig. 12).
If a supply of cooling water is not available, a
recirculating system with water-to-air heat ex-
changer can be used. For this system, correct
temperatures are maintained by automatic
thermal control of the motor-driven fan. CAU-
TION: For some locations and with a closed
recirculating cooling system, antifreeze com-
pounds are added to the recirculating water.
Some commercially available antifreeze com-
pounds become acid with use, and it is neces-
sary to test the solution periodically for acidity.
If acidity is shown, the system must be drained
and filled with fresh solution.
EASE OF INSTALLATION
Ignitron Rectifiers usually are assembled in
groups of six or more individual Ignitron tanks
or tubes. The assembly is mounted on a self-
supporting structural steel base, with bracing
and lifting members (see photo, below). The
assembly is complete with vacuum system,
cooling piping, valves, etc., and all parts within
the structure are complete with wiring for con-
trol and power connections to terminal blocks.
After installation, the only work involved is
connection of the control, power and water cir-
cuits to associated equipment. Auxiliary appa-
ratus such as insulating transformers, excita-
tion supply, hot wire gauge supply, vacuum
relays and control switches are mounted in an
Assembly of twelve Ignitions,
mounted on a structural steel
base.
auxiliary cubicle. The cubicle is completely
wired to terminal blocks.
Installed Anywhere
The Ignitron assembly, control switchboard
and heat exchanger (when used) may be in-
stalled in any room having a substantial and
reasonably level floor. The rectifier and heat
exchanger are self-supporting and require only
reasonably accurate alignment or leveling. The
switchboard may require wall supports or may
be built into a self-supporting structure. The
transformer may be constructed for indoor or
outdoor service, for mounting on the usual type
foundation.
Approved For Release 2001/03/06 : CIA-RDP83-00423R001900030002-6
27
:-RDP83 00423R001900030002-6
.10
"74 -?:.4" ????=,
Vacuum maintaining and indicating apparatus
is designed to properly evacuate the Ignitron
tubes and to indicate the pressure maintained.
This equipment is mounted on and forms an
integral part of the assembly. The system is
automatic in operation. (Fig. 13).
T/T011! , ? l'retti7WAVItad:
IleasISININM411.0110.11410T,M!
ESEvOffi-
-AND _
_ BAROMETRTC _
ROTARY
_
7/SWATS&
121G. 13 Schematic diagram of vacuum system.
The tubes of an ignitron assembly are mani-
folded and the vacuum is maintained by a
continuously operated mercury vapor vacuum
pump which pumps gas from the manifolding
through the mercury trap and discharges it
through a barometric tube into an interstage
reservoir. A rotary, oil-sealed backing pump,
pumps the gas from the interstage reservoir
and discharges it at atmospheric pressure.
Vacuum connections on the high-pressure side
of the interstage reservoir are made with flared
copper fittings. These fittings are small, fool-
proof and make reliably tight joints.
A Pirctni-type hot wire gauge connected to the
vacuum manifold continuously indicates the
pressure in the vacuum system and operates
to shut down the Ignition at high pressures.
A McLeod type gauge, manually operated, is
supplied for accurately reading the pressure
and calibrating the hot wire gauge. The aux-
iliaries are described in detail as follows:
Hand-Operated
Vacuum Valve
The vacuum valve for use between the mani-
fold and mercury vapor vacuum pump, is small
and compact by virtue of a flexible steel bel-
lows. The steel bellows, welded to the fixed
body and moving mechanism, provides a vac-
uum-tight operating mechanism. Valve seat is
of high-quality rubber, making a reliably tight
valve with little pressure exerted on the hand-
wheel. Movement of the valve disc is large as
compared to the opening in the valve body,
thereby minimizing pressure drop in this de-
vice when pumping gas from the vacuum sys-
tem. (Fig. 14).
,514;
magasseramilataztigamatailumnslo
FIG. 14 Hand operated vacuum valve.
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28
Approved For Release 2001/03/06 : CIA-RDP83-00423R001900030002-6
Mercury
Vapor Vacuum Pump
A mercury vapor diffusion pump is capable of
evacuating a vessel to a very low pressure, but
will not pump against a high back pressure.
The pressure to which a vessel can be reduced
with this pump is of the order of a fraction of a
micron. (One micron is the pressure which will
support a column of mercury 0.001 millimeter
high. Atmospheric pressure is 760 millimeters,
so one micron is, therefore, 1/760,000 of an
atmosphere).
The back pressure from a diffusion pump may
be stepped up by use of one or more ejector
nozzle type stages. The back pressure against
which a mercury diffusion pump will exhaust
is from 250 to 500 microns. In the three-stage
pump, two additional stages of the nozzle type
exhaust in series from the discharge of the
first, or diffusion stage, to a back pressure of
the order of 20 millimeters. (Fig. 15).
In the diffusion stage of a mercury vapor pump,
a blast of mercury vapor from a mercury boiler
is directed against a cooled surface at an angle
in which it is desired that the gas should flow.
This vapor is condensed when it strikes the
cooled wall, and the liquid mercury flows back
to the boiler through a trap. In this way there
is no vapor flowing toward the gas inlet of the
pump, and any permanent gas molecules which
diffuse into the stream of mercury are carried
along and prevented from returning. This prin-
ciple operates only with rarefied gases. Be-
cause of the low pressures of the gas, in order
to obtain a reasonable speed of pumping the
area of this stage is made large to present a
large opening into which the low-pressure gas
can diffuse. The second and third stages, which
deal with higher pressures, are made smaller.
The pump is so constructed that mercury vapor
is supplied from an electrically heated boiler at
the bottom of the pump, and is fed to the several
stages in parallel. A common cooling system
consisting of copper cooling coils provides cool-
ing around the stages, and the liquid mercury
is returned to the boiler through a series of
traps. The gas discharge tube is extended along
the edge of the cooling coils up toward the
pump intake, in order that any mercury tend-
ing to be discharged from the pump is con-
densed and returned to the boiler.
Design of the interior parts, nozzle spacings and
size of parts, make up a small, compact and yet
highly efficient pump. This pump, in contrast to
other commercial types, can be mounted di-
rectly on the Ignitron Rectifier assembly with
little increase in its over-all dimensions.
FIG. 15 Three-stage mercury vapor vacuum pump.
INLET
DIFFUSION
STAGE
SECOND
STAGE
THIRD
STAGE
MERCURY
BOILER
- - -
?
?
II ..emolke
II
6
DISCHARGE
CONNECTION
HEATER
INSULATION
HEATING
ELEMENT
ELECTRIC
HEATER
TERMINAL
NA.
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29
/06 : CIA-RDP83-00423R001900030002-6
110. 16 Interstage reservoir and barometric seal.
Interstage Reservoir
and Barometric Seal
rhe mercury vapor vacuum pump, pumps from
the Ignitrons into the interstage reservoir, from
which the gases are pumped to atmosphere by
the backing pump.
The barometric seal. consists of a tube some-
what longer than barometric height, with its
lower end immersed to a few millimeters in a
mercury pool. Gas being discharged from the
mercury vapor vacuum pump flows through the
tube and bubbles through the head of mercury
into the reservoir. (Fig. 16). The mercury pool is
large, in diameter so that if atmospheric pres-
sure reaches the interstage reservoir, mercury
will be forced up the tube to barometric height
without exposing the end of the tube, thereby
forming an inherently automatic vacuum seal
to the vacuum manifold. An oil trap in the upper
portion of the reservoir prevents oil from the
backing pump from coming in contact with the
mercury in the pool in the event of voltage fail-
ure to the backing pump driving motor.
A manometer type pressure gauge which shows
the pressure in the interstage reservoir is sup-
plied. This indication of the performance of the
backing pump is useful for tests of the vacuum
S ysterA
pweeivtitti FdicRWINVe020 0 1 /0 3/0 6
Rotary Oil-Sealed
Vacuum Pump
A direct-connected, slow-speed, three-phase
motor and pump operate continuously to ex-
haust the gas from the interstage reservoir.
Pumping action is obtained in this unit by the
rotation of a rotor that is eccentric to the pump
frame. Two radially movable blades force the
gas from the pump intake to the discharge. Oil
in the pump seals the blades, the rotor and
frame, making the compartments formed be-
tween intake and discharge vacuum-tight when
the pump is operating.
The Westinghouse rotary vacuum pump will
pump down to a pressure of less than one milli-
meter of mercury with an average pumping
speed of about 0.3 liters per second. A direct-
connected vertical pump eliminates the neces-
sity for stuffing boxes and eliminates oil leak-
age from the oil reservoir mounted around the
pump proper. The close manufacturing toler-
ances, the absence of gears and the smallness
of parts combine to make a quiet-operating
unit. (Fig. 17).
17 Rotary, oil-sealed vacuum pump.
McLeod Vacuum Gauge
In high vacuum (low-pressure) practice where
pressures of the order of one micron are en-
countered, a special form of gauge is required
because the eye cannot detect directly such
small differences in balanced mercury column
heights. The McLeod gauge gives an accurate
reading of low pressures by taking a sample of
the gas and compressing it to a degree where
it will support a head of mercury to a readable
: CrAl-RDOSA)0423R001900030002-6
10
:CIA
CONNECTING
TUBE
1
SCALE LENS
PLATE
MERCURY
CHAMBER
IGHT
LIFTING
CAM
STEEL
-BE L?WS .
FIG. 18 McLeod vacuum gauge.
By the use of a flexible steel bellows, the height
of this gauge is reduced to practically one third
the height of other commercial gauges. The
steel bellows assembly is completely welded,
thus eliminating any leaks that would affect
the accuracy of the gauge. Once this gauge is
completely degassed, it remains so since no
materials are used in the vacuum chamber
which continue to give off gases for long periods
of time. A miniature light to facilitate taking
readings is mounted back of the translucent
scale plate. This gauge will read pressures
varying from 0 to 500 microns, the logarithmic
scale making the lower values more accurate.
Hot Wire Vacuum Gauge
The Pirani-type, or hot wire, vacuum gauge is
used to continuously indicate the pressure in
the Ignitron unit and prevent its operation at
excessive pressures. This gauge operates on
the pressure-thermal conductivity principle
which, with Wheatstone Bridge to detect
changes in the resistance of the hot wire fila-
ment, indicates pressure. One filament in a
glass tube exposed to the pressure in the Igni-
tron vacuum manifold forms one leg of the
bridge, a compensating bulb completely evac-
uated and sealed off forms another leg, and
two variable resistors complete the bridge cir-
cuit. The presence of gas in the unsealed tube
affects the rate at which heat is lost by the fila-
ment. This, in turn, changes the filament resis-
tance and the bridge balance. The indicating
and contact-making instruments, calibrated in
microns, indicate the pressure and operate to
remove the unit from service on high pressure.
(Fig. 19).
This gauge is affected not only by a permanent
gas, but also by mercury vapor, although less
affected in the ratio of the molecular weights
of mercury and air. The gauge is located on
the vacuum system so that practically all va-
PR)Ond1416sCT 0e0Y regagig 61}bdidr: CIA
31
FIG. 19 Hot wire vacuum gauge, with cover removed.
by giving indication principally of permanent
gases.
The hot wire gauge bridge, complete with both
bulbs and resistors, is arranged in a small,
compact unit. Usually it is mounted directly
above the McLeod gauge so that during cali-
bration there is no difference in pressure due
to different locations of the gauges in the vac-
uum system.
Three-Way
Vacuum Gauge Valve
The three-way bellows valve is designed to
make connection between the vacuum mani-
fold, the Pirani gauge and the McLeod gauge.
It is a low-capacity, low-pressure valve that can
be used where it is necessary to maintain a
nearly perfect vacuum. The vacuum-tight mov-
able element is obtained by the use of a steel
bellows, welded to the compression ring and
valve stem, as is shown in Fig. 20. The vacuum
seal in the valve assembly is made by com-
pressing the rubber gasket between the com-
pression ring and the valve body.
FIG. 20 Cross-sectional view of three-way type vacuum
valve.
GASKET SEAT
- THREADED
TO HOT WIRE GAUGE
RUBBER GASKET
NM\ NMI
1100Rpoar
Nnk.
m.00.7tik7.?
_
eritiMIL
COMPRESSION
RING
FLANGE
TO VACUUM
MANIFOLD
OF THE
RECTIFIER
VALVE BODY
TUBE_ VACUUM VALVE
WRENCH TO TURN
?
',AUG isE.LOWS
ASSEMBLY
32
Approved For Release 2001/03/06 : CIA-RDP83-00423R001900030002-6
Surge Suppressors
Voltage surges tend to occur in applications
where suddenly applied loads may be en-
countered with low water temperatures. Volt-
age surge elimination is accomplished by con-
necting a capacitor of adequate size in series
with a resistor from each anode to cathode, to
damp out any oscillations. Since surges are
due to instability in the arc under abnormal
conditions, their elimination is best accom-
plished by provisions c:t the source.
Degassing Equipment
Atter an Ignitron Rectifier is assembled, it must
be subjected to a degassing process in order to
remove all of the foreign gases before it is suit-
able for operation at its rated voltage. This con-
sists of evacuating the rectifier and applying
current somewhat above its rating, but at low
voltage, to raise the temperature of all parts to
somewhat higher than normal temperatures
and drive off the absorbed gases. If an Ignitron
in service is opened to atmosphere for any
reason, it must be re-degassed before being re-
placed in operation. However, after a rectifier
has once been thoroughly degassed, the re-
degassing is a relatively short process, unless
the interiors of the tubes have been exposed to
atmosphere for a long time.
For the purpose of degassing, transformer low-
voltage degassing taps can be provided with
terminals brought to a terminal board within
the transformer. In many cases where there are
a large number of rectifiers on a system? or
where partial capacity operation is contem-
plated while degassing one section, i.t proves
more convenient to provide a separate degas-
sing transformer.
In either case, the degassing current is regu-
lated by ignitor control of the direct-current
voltage.
Visible gauges permit careful
checking of the degassing
operation.
Testing an 1gnitron Rectifier.
Approved For Release 2001/03/06 : CIA-RDP83-00423R001900030002-6
IGNITRON RECTIFIER POWER SUPPLY
TRANSFORMERS
Conditions under which Ignitron Rectifier trans-
formers operate differ in one essential respect
from those for rotating machines, in that the
d-c windings carry practically no current dur-
ing certain portions of the voltage cycle. The
duration of the conducting and nonconducting
periods is determined by the cyclic polarities
of the transformer windings, and by the valve
action of the rectifier anodes. This mode of
operation results in higher transformer losses
and increases d-c kva rating required for a
given kilowatt output from the rectifier. It also
results in the a-c and d-c windings being of
unequal capacity. As a consequence, rectifier
transformers are fundamentally more costly
than ordinary transformers based on the same
kva input rating.
Various transformer windings and connections,
which subject the anodes to various current
intensities during the conducting cycle, are pos-
sible. In general, the types of windings which
subject the anodes to lesser current intensities
result in more economical transformer designs.
Interior it) f trcrnformer showin
MorpJicxso cmsform
Approved For Release 2001/03/06
Approved For Release 2001/03/06 : CIA-RDP83-00423R001900030002-6
Interphase Transformers
Westinghouse transformers utilize interphase
transformers between wye or zigzag groups of
d-c windings which cause the groups to operate
as independent, three-phase units. The inter-
phase transformers displiace the neutrals of the
groups in voltage relation so that essentially
six to twelve-phase operation of the Ignitron is
obtained, but with the i:aherent advantages of
three-phase operation in which each winding
carries current for 120 electrical degrees.
This type of connection may be characterized
as superior in the following important respects:
Simplicity.
-High utility factor on basis of ratio of d-c
winding kva to kw.
Causes Ignitron anodes to operate under
most favorable conditions.
increased capacity of Ignitron to handle ex-
u eme overloads.
Use of the interphase transformer, which pro-
vides the benefit of three-phase operation of
transformer secondary windings and rectifier-
anodes, inherently introduces the disadvantage
that at very low currents (below the value re-
quired to magnetize the core of the interphase
transformer) operation reverts to six-phase and
there is a sharp voltage rise which amounts to
a theoretical value of approximately 15 per
cent. Special provisions have been made in the
design of Westinghouse interphase transfor-
mers so that this voltage rise takes place at
an extremely small load, approximately six-
tenths of one per cent of the unit rating.
En most cases this is satisfactory. Where there
is a great amount of zero load operation and
where voltage rise is a serious disadvantage,
means can be provided for separate excitation
of the interphase transformer iron, or a phantom
load provided to completely eliminate this no-
load voltage rise. (Fig. 21).
FIG. 21 Voltage rise at light load when using interphase
trans., ormers.
720
700
41.1
LD 680
di 660
640
When a rectifier is operated with the voltage
reduced by ignition delay, the duty on the
transformer and interphase transformer is in-
creased, and this type of operation must be
given consideration in the design. Particularly,
the size of the interphase transformer must be
increased if the intended load involves opera-
tion at large angles of delay.
Transformer equipment has been designed to
provide uniform impedances in the three-phase
groups, and they are so arranged that the
load divides evenly between them, and conse-
quently divides evenly between the Ignitron
anodes. Accurate balance is important in recti-
fier transformers to avoid unbalanced currents
and distorted wave form. Westinghouse trans-
formers are not only accurately balanced but
are also rigidly braced to withstand short cir-
cuits on the rectifier and the more severe
stresses of the unbalanced short circuits due to
arc-back, without damctge. The main and inter-
phase transformers can be mounted in the same
or separate tanks, whichever is most conve-
nient for the station.
Direct-Current Voltage
Regulation
FIG. 22 Direct-current voltage characteristic.
The direct-current voltage characteristic of an
Ignitron Rectifier unit is determined almost
wholly by the transformer. Arc-drop or voltage
loss in the rectifier as essentially constant
throughout the normal load range. The de-
crease in direct-current voltage as the load is
increased is caused principally by the increase
in resistance and the reactance drop in the
transformer windings. With a transformer of
normal design, the resultant regulation is of
the order of 5 or 6 per cent. In a majority of
applications this is the type of regulation that
is needed. (Fig. 22). This normal characteristic
can be altered, however, by use of ignition
control, where desirable.
Ignition control is accomplished by delaying
the ignition impulses to the ignitors. The trans-
former must be designed to provide the highest
Far Relcase 20 1/03tai ? CIA-RDP83-00423R001900030002-6
01 0.2 0.3 0.4 34
PER CENT LOAD
Approved For Release 2001/03/06 : CIA-RDP83-00423R001900030002-6
voltage desired, and d-c output is reduced from
that value by delaying the point of pickup by
shifting the phase position of the excitation
supply. This delay can be accomplished man-
ually or automatically (with a conventional
voltage regulator) as indicated by the applica-
tion. Inherent compensation or modification of
normal regulation can be obtained by other
connections. This method of control provides
an extremely smooth and rapid variation of
voltage output, but is accomplished at some
expense of power factor and wave form. (Fig.
23 and 24).
6
ANSFO MER TO NEUTRAL VOLTAGE
1 2 3 4 5 6
4
/ 4
RESULTANT /\
D-C VOLTAGE \
\ TIME
/
/
/
/
I..." 'RR ????
I I
FULL LINES-GROUP I
1-3-5 41 144-ANGLE OF OVERLAP
OTTO LINE$-GROup 2_4.4
?
FIG, 23?Wave shape with zero ignitor delay.
IPANSFORMER TO NEUTRAL VOLTAGE
1 2 3 4 5 6
-r--. -r--.
4441P4 44N 44NA
A ? /\
Y ?
i 1 ' U I 4
RESULTANTs !
%I / % 1
-C VOLTAGE% i ?i
/ %!
\
' TIME/ lir I /I V \ /
\1 / \ /
1 / \ // \ /
\ / \ I/ \
I lk
A
I
, ,
, , ? \ , ?
, , , 1 \ 1
, 1
? , 1 \ 1
..,........? r...,___.?
FULL LINES-GROUP' -41 14-ANGLE OF OVERLAP
I I
1.3-5, I , 0?ANGLE OF DELAY
DOTTED LI'NES-GROUP 2-4-6
FIG. 24--Wave shape with 300 ignitor delay.
The normal rectifier regulation can be made to
parallel with other forms of conversion appara-
tus with the usual shunt characteristic. Through
use of ignition control, it is possible to obtain
parallel operation with machines having vari-
ous degrees of compounding. Since the d-c out-
put voltage of synchronous converters and
rectifiers depends upon the high line voltage in
the same manner, parallel operation of a rec-
tifier with a converter is simpler than with a
FIG. 25 Typical efficiency curves of 1500-kw, 250-volt and
motor generator, the d-c voltage of which is 1500-kw, 600-volt leritron units. The influence of voltage
iridAppitiVed iftdri
EFFICIENCY
Efficiency of an Ignitron Rectifier unit is the
ratio of the power output at the d-c terminals
to the power input at the high tension terminals
of the transformer. Component losses of the
unit included in the efficiency calculations are:
the copper and iron losses of the transformer
equipment, the loss in the rectifier arc and the
power for operation of the standard rectifier
auxiliaries.
For a given kilowatt output, the efficiency of
any arc rectifier unit improves as the direct-
current voltage is increased. Losses of the trans-
former are in proportion to kilowatts, but the
arc loss of the rectifier is practically in pro-
portion to d-c amperes. The lower the ratio
of d-c amperes to kilowatts, the higher the
efficiency.
Throughout the normal load range, the arc
volts drop is practically constant, there being
only several volts difference in arc-drop be-
tween light load and full load. The volts drop
in the arc at any given d-c ampere load is
determined by rectifier design.
For 250-volt d-c operation, the Ignitron unit effi-
ciency is higher than that of a motor generator
set throughout the normal load range. It is
higher than the efficiency of a synchronous
converter up to 75% load, and lower beyond
75% load.
For 600-volt, d-c operation, the Ignitron unit effi-
ciency is higher than that of a motor generator
set throughout the normal load range. It is
higher than the efficiency of a synchronous
converter throughout the normal load range.
For operation at d-c voltages above the 600-
100
95
90
tti
85
80
Bill
111.111.111111111111
...4000..._
isami.al
gli_
011111110111.11111111111111
AI 00 KW, 200 VOLTIGNITRON
RECTIFIER
8-1500 KW, 00 VOLT SYNCHRONOUS CONVERT R
C-I500 KW,
2.50-001.1 SYNCHRONOUS MOTOR GENERATOR SET
0-1100 KW,
OGVOLT IGNITRON RECTIFIER
1-1500 KW,
'-I 00 KW, 60040
OGVOLT SYNCHRONOUS CONVERTER
LT SYNCHRONOUS MOTOR GENERATOR SET
ill
1 I
25 50 75
PER CENT LOAD
100
125
reitsse20 0 /03/06 : CIA.RDM340 23R004900&30002,4
35
Approved For Release 2001/03/06 : CIA-RDP83-00423R001900030002-6
volt d-c class, the Ignitron unit efficiency is
higher than that of all rotating conversion units
throughout the normal load range.
Due to the considerably higher efficiency of the
Egnitron unit as compared with rotating units
at light loads, its application is particularly ad-
vantageous on low load factor installations.
POWER FACTOR
The power factor of a rectifier installation is
determined by the operating conditions, the
transformer characterislcs and connections,
and the constants of the supply circuit. Power
factor of a rectifier is generally understood to
be the ratio of input power to the product of
the rms voltage and rms amperes of the a-c
supply. Consequently, power factor depends
upon both reactive volt-amperes and effects of
wave distortion. Fig. 26 shows the power factor
of typical six-phase and twelve-phase rectifiers
supplied from a large a-c system.
RATINGS
Rectifiers are rated according to the standards
which apply in the service for which they are
intended. In case the accepted standards do
not fit the expected loading, special ratings
may be used. Rated overloads and high mo-
mentary swings have no injurious effects on
mercury arc rectifiers in contrast to rotating
machinery--so overloads specified in the rat-
100
95
or
o 90
or
85
or
?- so
FIG. 26 Typical power-factor curves.
12 PHASE WITH 9% REACTANCE
C6 PHASE WITH 6% REACTANCE
25 50 75 100 125 150
PER CENT LOAD
ings are available for regular operation with-
out involving additional maintenance costs.
Overload cycles must be separated by inter-
vals of full load or less operation of sufficient
length to permit the rectifier and transformer
to reach normal full load temperatures
RECTIFIER HARMONICS
The d-c output voltage and a-c supply current
contain harmonics which are inherent in the
operation of a rectifier and are similar to the
slot or commutator ripples or other harmonics
produced by rotating machines. These har-
monics are of relatively small magnitude and
may be safely ignored in the majority of in-
stallations. If the rectifier constitutes a large
percentage of the total load on the power
supply system, however, it may be desirable
to give consideration to the possibility of in-
creased heating in the a-c generator.
There is also the possibility that harmonics
from a rectifier may give rise to an inductive
co-ordination problem if either d-c or a-c supply
lines of the rectifier are located in close prox-
imity to communication circuits. This problem
together with other noise problems has received
careful consideration by power and communi-
cation system engineers. In general, these prob-
lems may be solved by means applicable to
(1) the power system, (2) the communication
system, (3) the coupling between the systems,
or a combination of these methods.
Where a wave shape problem is encountered
and remedial measures applicable to power
supply equipment are indicated, these will take
the form of a larger number of phase positio:ns
in the rectifier, where this is possible, or of
filtering equipment. To reduce harmonics in the
d-c circuits, filtering equipment would include
one or more shunt elements, each consisting of
a reactor and capacitor connected in ser les and
tuned to a harmonic frequency.
The resonant shunts will ordinarily be used in
combination with a reactor connected in the
main d-c circuit. To reduce the harmonics in the
a-c circuit, the filter equipment will consist of
one or more sets of tuned shunt elements con-
nected across each of the three phases of the
supply. Experience has proved that filters for
the a-c circuits are rarely required.
Approved For Release 2001/03/06 : CIA-RDP83-00423R001900030002-6
71i;
DISCONNECT
SWITCH
AUXILIARY
TRANSFORMO
INSULATING
TRANSFORMER
THERMOSTAT
ELEMENT
CONTACTOR
COIL
THERMO-
STAT
INTERPHASE
TRANSFORMER
WATER WATER
CIRCULATING HEATERS
PUMP
ROTARY MERCURY
VACUUM VACUUM
PUMP PUMP
HEATER
SHIELD
,r-IGNITOR
TO
SHIELDS
CHARGING
TRANSFORMER
METER
PHASE SHIFT
REACTOR
FIRING
CAPACITOR
0-1*-.44
TO IGNITORS
TO D.C.
REGULATING
CONTROL
SATURATING
REACTOR
PIRANI GAUGE
BRIDGE CIRCUIT
TO
IGNITORS VACUUM/
SYSTEM
D-C BREAKER
D-C BUS
DENdIfloa 9,1411H3LIMS
?-Z000?00061,00NEZ1700-EacKIN-V10 : 90/?0/1.00Z eseeieN iod peAcu ? ? vA
ApprovedFor Release2001/03/06 : CIA-RDP83-00423R001900030002-6
Witching Equipment
Switching equipment is available to meet the
various applications ranging from manual to
full automatic control. Automatic control of an
Igmtron Rectifier station is very simple.
In a manually controlled station the operator is
responsible for performing in their proper se-
quences the various steps required to place the
unit in operation. The vacuum pumping system
normally is in continuous operation. This is true
with, both manual and automatic control, and
regardless of whether the rectifier is carrying
load or is shut down. (Fig. 27).
Placing the Ignitron in service, the operator
first checks the system vacuum to see that it is
within safe operating limits. He then closes the
high tension a-c breaker which energizes the
main power transformer so that potential is
applied to the rectifier anodes. The excitation
equipment is next placed in operation. Ignition
of the main anodes follows, and then the d-c
line breaker is closed. This completes the start-
ing operation and the rectifier now delivers its
share of the load to the system.
Full Automatic Control
When full automatic control is supplied, all of
the above operations are performed auto-
matically. The Ignitron is placed in operation
or shut down by one or more of the usual
methods. Among the most common of these
are undervoltage starting and light load stop-
ping, remote pushbutton control and supervi-
sory control.
Vatious degrees of semiautomatic control are
available also to supply the demand for this
type of equipment. Generally speaking, these
forms of control require an operator to place
them in service, after which they operate with-
out attention until taken out of service, either
by the operator or due to operation of one or
more of the protective devices.
Even in manually operated stations many of
the automatic features usually are retained, for
instance a provision for shutting down a unit
in the event of loss of vacuum or overtempera-
ture, although frequently the arrangement is
such that these conditions sound an alarm.
Protective Devices
With full automatic control, full protection must
be provided to take care of any emergency
that may arise. These protective features can
be divided into two classes. Those in the first
group prevent the rectifier from operating until
after the emergency has passed, when it is
again released for service. Functioning of a
device in the second class effects a complete
station lockout until someone visits the station
to correct the trouble and reset the lockout
relay. Devices of this class are reduced to a
minimum with Ignitron Rectifiers.
The design of control and protective eauipment
for an Ignitron Rectifier, while eliminating a
great many features necessary for the control
and protection of rotating machines, introduces
a number of considerations not encountered in
connection with this type of conversion appara-
tus. These differences have been recognized
and suitable apparatus developed to provide
the same surety of protection, correctness of
sequence and high degree of service reliabil-
ity which characterize Westinghouse automatic
switching for other classes of equipment.
Approved For Release 2001/03/06 : CIA-RDP83-00423R001900030002-6
38
FOROMMETEelleRNATIONAIMPIGNIIIIONiREVIVIERS
SEE THE WESTINGHOUSE OFFICE NEAR YOU
LOCATION ADDRESS TELEPHONE
AKRON 8, OHIO, 106 S. Main St. Jefferson 3165
ALBANY 4, N. Y., 456 N. Pearl St. 5-1597
ALBUQUERQUE, N. M., 11151/2 E. Central Ave. 3-1826
ALLENTOWN, PA., 739 Hamilton St. 4-5108
AMARILLO, TEXAS, 303 Amarillo Bldg. 7838
APPLETON, WIS., 321 West College Ave., 1. 0. Box 206 ...4-4116
ATLANTA 2, GA., 1299 Northside Drive, N. W. Atwood 1642
AUGUSTA, MAINE, 9 Bowman St. 2463
BAKERSFIELD, CALIF., 2224 San Emidio St 2-4381
BALTIMORE 2, MD., 501 St. Paul Place Plaza 0300
BEAUMONT, TEXAS, 515 American National Bank Bldg. ....41481
BINGHAMTON 62, N. Y., 704 Marine Midland Bldg. 2-6403
BIRMINGHAM 3, ALA.. 1407 Corner Bldg. 3-8137
BLUEFIELD, W. VA., 704 Bland St., P. 0. Bcx 848 39131
BOSTON 10, MASS., 10 High St. Liberty 2-0600
BRIDGEPORT 8, CONN., 540 Grant St. 4-0151
BUFFALO 3, N. Y., 814 Ellicott Sq. Bldg. Washington 3966
BUTTE, MONT., 1 East Broadway 2-2301
CANTON 2, OHIO, 120 W. Tuscarawas St. 39171
CEDAR RAPIDS, IOWA, 512 Dows Bldg., P. 0. Box 1828 ....7638
CHARLESTON, S. C., 89 G. Smith St. 9904
CHARLESTON 1, W. VA., 179 Summer St., P. 0. Box 911...37-565
CHARLOTTE 1, N. C., 210 E. Sixth St. 5-3731
CHATTANOOGA 2, TENN., Volunteer Stab?. Life Bldg. 7-4361
*CHICAGO 6, ILL., 20 N. Wacker Drive Franklin 2-5520
CINCINNATI 2, OHIO, 207 W. Third St. Garfield 2250
CLEVELAND 13, OHIO, 1370 Ontario St. Cherry 1-7600
COLUMBUS 15, OHIO, 262 N. Fourth St. Main 4134
CORPUS CHRISTI, TEXAS, 416 N. Chaparral St. 3-9237
DALLAS 1, TEXAS, 209 Browder St. Randolph 4161
DAVENPORT, IOWA, 2212 E. 12th St., P. 0. Box 29 3-2761
DAYTON 2, OHIO, 32 North Main St. Adams 9153
DENVER 2, COLO., 910 Fifteenth St. Keystone 8121
DES MOINES 8, IOWA, 1400 Walnut St. 2-0244
DETROIT 31, MICH., 5757 Trumbull Ave., Box 828 ..Trinity 2-7010
DULUTH 2, MINN., 10 East Superior St. Melrose 821
EL PASO, TEXAS, 718 Mills Bldg. .2-5691
EMERYVILLE 8, CALIF., 5815 Peladeau St. Olympic 2-3770
ERIE, PA., 1003 State St 24-867
EVANSVILLE 8, IND., 106 Vine St. 5-7146
FAIRMONT, W. VA., 10th and Beltline 501
FERGUS FALLS, MINN., 1011/2 W. Lincoln St. 4250
FORT WAYNE 2, IND., 610 S. Harrison St. Anthony 3421
FORT WORTH 2, TEXAS, 408 West Seventh Street ..Fortune 4086
FRESNO 1, CALIF., 2608 California Ave. 6-6489
GARY, IND., 846 Broadway 2-1468
GRAND RAPIDS 2, Mich., 148 Monroe Ave., N. W. 9-3106
GREENSBORO, N. C., 1008 Pamlico Drive 2-3415
GREENVILLE, S. C., 160 W. Tallulah Drive 3-7755
HAMMOND, IND., 235 Locust St. Russell 8937
HARTFORD 3, CONN., 119 Ann St., 7-8141
HOUSTON 2, TEXAS, 1314 Texas Ave. Charter 4691
HUNTINGTON I, W. VA., 1029 Seventh Ave., P.O. Box 1150 .7146
INDIANAPOLIS 9, IND., 137 S. Pennsylvania Street Market 3301
JACKSON, MICH., 180 West Michigan Ave. 2-0519
JACKSON, MISS., P. 0. Box 4296, Fondren Sta. 2-3527
JACKSONVILLE 3, FLA., 37 South Hogan St. 3-7431
JAMESTOWN, N. Y., 300 Wellman Bldg., 101 West 3rd St. ...3042
JOHNSTOWN, PA., 107 Station St. 81-257
KANSAS CITY 6, MO., 101 W. Eleventh Street Harrison 7122
KNOXVILLE 8, TENN., 605 Burwell Bldg. 2-8101
LITTLE ROCK, ARK., 707 Boyle Bldg. 4-0368
LOS ANGELES 17, CALIF., 600 St. Paul Avenue ..Madison 6-3881
*After March 1, 1951: Mdse. Mart Plaza, Chicago 54, Illinois
Appr
LOCATION
ADDRESS TELEPHONE
LOUISVILLE 2, KY., 332 West Broadway Clay 0212
MADISON 3, WIS. 1022 E. Washington Ave. Badger 4990
MEDFORD, OREGON, 38 N. Bartlett St., P. 0. Box 1308 8-289
MEMPHIS 3, TENN. 825 Exchange Bldg. 8-8546
MIAMI 4, FLA., 11 N. E. Sixth St. 8-23691
MIDDLESBORO, KY., 2019 Cumberland Ave., P. 0. Box 517 ...221
MILWAUKEE 2, WIS., 538 N. Broadway Daly 8-1800
MINNEAPOLIS 13, MINN., 2303 Kennedy St.,N. E. ..Granville 3545
MOBILE, ALA 171 Emogene Place 6-2215
NASHVILLE 3, TENN., 6th Ave. at Shirley St. 42-3505
NEWARK 2, N. J., 1180 Raymond Blvd. Market 2-0200
NEW HAVEN 10, CONN., 42 Church St. 5-3191
NEW ORLEANS 13, LA., 238 South Saratoga Street ..Raymond 8656
NEW YORK 5, N. Y., 40 Wall St. Whitehall 3-4321
NIAGARA FALLS, N. Y., 253 Second St. 9700
NORFOLK 10, VA., 915 W. 21st St. 5-1639
OKLAHOMA CITY 2 OKLA., 120 N. Robinson St. 7-1633
OMAHA 2, NEBR 117 North Thirteenth St Harney 8700
PEORIA 2 ILL., 418 S. Washington St. 7116
PHILADELPHIA 4, PA., 3001 Walnut St. EVergreen 2-1200
PHOENIX ARIZ 11 West Jefferson St. 4-3158
PITTSBURGH 30, PA., 306 Fourth Ave. Atlantic 1-8400
PORTLAND 4, ORE., 309 S. W. Sixth Ave. Atwater 9464
PROVIDENCE 3, R. I., 16 Elbow St. Gaspee 1-0818
RALEIGH, N C. 803 North Person St. 6302
READING, PA., 4th and Elm Sts. 7236
RICHMOND 19, VA., 1110 E. Main St. 2-4758
ROANOKE 4, VA., Kirk Ave. and First St., P. 0. Box 599 ....6263
ROCHESTER 7, N. Y., 1048 University Ave. Monroe 1635
ROCKFORD, ILL., 323 S. Main St. 2-3452
RUTLAND, VT., 98 Merchants Row 3292
SACRAMENTO 14, CALIF., 1720 Fourteenth Street ..Gilbert 3-6525
SAGINAW MICH., 124 So. Jefferson St. 4-2640
ST. LOUIS 1, MO., 411 North Seventh St. Central 1120
SALT LAKE CITY 1, UTAH, 235 West South Temple St. ....5-3413
SAN ANTONIO 5, TEXAS, 115 West Travis Street Garfield 5114
SAN DIEGO 1, CALIF., 861 Sixth Ave. Main 8151
SAN FRANCISCO 8, CALIF., 410 Bush St. Exbrook 2-5353
SEATTLE 4, WASH., 3451 East Marginal Way Main 0808
SHREVEPORT, LA., 222 Spring St. 4-5298
SIOUX CITY 4, IOWA, 1005 Dace St. 5-7634
SOUTH BEND 4, IND., 216 E. Wayne St. 3-7167
SPOKANE 8, WASH., 1023 W Riverside Ave. Main 3294
SPRINGFIELD, ILL., 517 Illinois Bldg., P. 0. Box 37 3-1532
SPRINGFIELD 3, MASS., 26 Vernon St. 6-8373
SYRACUSE 4, N. Y., 700 W. Genesee St. 2-1361
TACOMA 2, WASH., 1930 Pacific Ave. Broadway 6565
TAMPA 1, FLA., 909 Wallace S. Bldg., 608 Tampa St. 2-2542
TOLEDO 4, OHIO, 245 Summit St. Garfield 4625
TRENTON 10, N. J., 1100 S. Broad St. 2-4136
TULSA 3, OKLA., 619 S. Main St. 3-3191
UTICA 1, N. Y., 113 N. Genesee St. 4-1194
WALLA WALLA, WASH., 17 N. Second Ave., P. 0. Box 182 ..5124
WASHINGTON 5, 11. C., 1625 "K" St., N. W National 8843
WATERLOO, IOWA, 300 W. Third St. 4679
WATERTOWN, N. Y., 245 State St. 1400
WHEELING. W. VA., 12th and Main Sts., P. 0. Box 329..6222-6223
WICHITA 2, KANSAS. 301 S. Market St. 5-2631
WILKES-BARRE, PA., 267 N. Pennsylvania Ave. 3-1144
WILLIAMSPORT 1, PA., 348 W. Fourth St. 4289
WORCESTER 8, MASS., 507 Main St. 4-2648
YORK, PA., 11 W. Market St. 7851
YOUNGSTOWN 3, OHIO, 25 E. Boardman St. 4-1118
eigerdaltallinaltIECIMIRS
Ft 3024-A
Westinghouse Electric Corporation
EAST PITTSBURGH, PENNA.
Approved For Release 2001/03M--:-C -RDP83-00423R001900030002-6
71/2M-2/51
Printed in U.S A
Approved For Release 2001/03/06 : CIA-RDP83-00423R001900030002-6
L.
111-TILIAS
NEETRIPT
ROUTING AND CONTROL RECORD
DO NOT DETACH FROM 'ON LOAN' DOCUMENTS
21 April 1955
DATE
TO:
Graphics ReRister 25X1A9a
ATTN:
BUILDING
-
ROOM NO.
TITLE
Pictures of 6,000 Ampere Ignitron Built in
US for USSR
25X1A2g 25X1A2g
REMARKS R-23853
Qiad RETAIN
I I ON LOAN
DOCUMENT(S)
FOR RETENSION
BY ADDRESSEE
DOCUMENT(S) MUST BE RETURNED TO
CONTACT DIVISION/00
BY (DEADLINE)
25X1A8a 5X1A9a
FROM:
CONTACT DIVISION/00
EXTENSION
2576
BUILDING
Quarters Ee
ROOM .
18Q8
Approved For Release 2001/03/06 : CIA-RDP83-00423R001900030002-6
oved For Release 2001/03/06 : CIA-RDP6300423R001900030002-6'