GE CLPG12C User manual

INSTRUCTIONS
CARRIER CURRENT GROUND RELAY
CLPG12C
GENERAL ELECTRIC
GEI-8391OG

GEI-83910
TABLE OF CONTENTS
PAGE
INTRODUCTION
........................ . . . . . . . . . . . . . . . . . . . . . .. ....... 3
APPLICATION .............................. . . . . . . . . . . . . . 3
RATINGS .......................... ......... 4
COILS ......... ....... ................................... 4
CONTACTS ................ ....................................... 4
CHARACTERISTICS ......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
OPERATING PRINCIPLES .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
PiCKUP................. .......................... ...... ........ 5
OPERATING TIME ................................................... 5
BURDEN
................ .......................................... 5
CALCULATIONS OF SETTINGS ............................................... 5
TWO-TERMINAL LINE ...................................................... 6
THREE-TERMINAL LINE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 6
CONSTRUCTION ............... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 7
CARRIER-START UNIT (G-1) ................................................. 7
TRIP UNIT (G-2) ........... . . . . . . . . . . . . . . . . . . . . . . . .. .................. 8
DIRECTIONAL UNIT (GD) ................................................... 8
AUXILIARY UNIT (GD1X) ................................................... 8
SEAL-IN UNIT (SI) ................... . . . . . . . . . . . . . . . . . . . . . . 9
RECEIVING, HANDLING, AND STORAGE .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 9
ACCEPTANCE TESTS ............................................................ 9
VISUAL INSPECTION ................ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 10
MECHANICAL INSPECTION ................................................ 10
ELECTRICAL
TESTS ........................................................ 10
Upper-Unit Pickup (G1) ........................ ............... 10
Middle-Unit Pickup (G2) ........... . . . . . . . . . . . . . . 11
Bottom-Unit Pickup (GD) ........... . . . . . . . . . . . . . . . . . . . .. 11
Bottom-Unit-Core Check (GD) ....... . . . . . . . . . . . . . .. 11
GD1X Unit Pickup ........................ . . . . . . . . . . . . . . . . . . . . . .. 11
INSTALLATION PROCEDURE .......... ....................................... 11
RELAY SETTINGS .................. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 11
CARRIER-PICKUP-START UNIT (G1) .... ................................... 12
CLUTCH ADJUSTMENT........ .................................... 12
TRIP UNIT (G2) .......................................................... 12
CLUTCH ADJUSTMENT
.................................................... 13
DIRECTIONAL UNIT (GD) ........................ . . . . . . . . . . . . . . . . . .. 13
PERIODIC CHECKS AND ROUTINE MAINTENANCE. . .. . . . . . . . . . . . . . .. 13
MECHANICAL CH ECKS ............................. 14
ELECTRICAL TESTS ............. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 14
SERVICING .................................................... . . . . . .. 14
MECHANICAL ADJUSTMENTS ....................................... 14
ELECTRICAL ADJUSTMENTS . . . . . . . . . . . . . . . 15
RENEWAL
PARTS... .......... ...................................... 16
LIST OF FIGURES...... ........ .......................... 17
(Cover Photo 8029772)
)

GEI-83910
CARRIER CURRENT GROUND RELAY
CLPG12C
I NTRODUCTI ON
The CLPG12C is a high-speed, zero-sequence ground relay designed specifically
for use as a ground-fault relay in directional-comparison relaying schemes. This
relay contains one high-speed zero-sequence directional unit, which may be
po 1 ari zed from voltage and/or current. It also contains two hi gh-speed zero-
sequence non-directional overcurrent units and one direct-current-operated (DC)
aux il iary unit. The CLPG12C is packaged ina size-L2 case and incl udes a target
and a separate seal-in unit. One CLPG12C is required per terminal.
APPLICATION
The CLPG12C finds application on grounded neutral systems as the directional-
comparison ground relay in directional-comparison schemes, regardless of the type
of channel
that is used. This relay, operating in conjunction with the pilot
channel and the CLPG12C relays at the other ends of the protected 1ine section,
provides high-speed tripping for all single-phase-to-ground faults in the protected
line section.
The two non-di rect i ona 1 overcurrent uni ts and the operat i ng ci rcuit of the
directional unit may be all supplied in series from the neutral connection of the
three line-current transformers. The polarizing circuit of the directional unit
may be supplied from a current transformer in the neutral of a grounded neutral
power transformer or from the broken-delta secondary connection of three potential
transformers whose primary windings are connected in wye, or it may be
simultaneously supplied from both sources of polarization.
These instructions do not purport to cover all details or variations in equipment nor provide {or every
possible contingency to be met in connection wilh inst.allation, operation or maintenance. Should {urther
in{ormation be desired or should particular problems arise which are not covered sufficiently for the purchaser's
purposes, the matter should be referred to the General Electric Company.
To the ex/ent required the products described herein meet applicable ANSI, IEEE and NEMA
standards; bllt no such assurance is giuen with respect to local codes alld ordinances because they vary greatly.

GEI-83910
The
sensitivity of each of the overcurrent units, as well as that of the
directional unit, is adjustable over the ranges specified under RATINGS. The
operating times of the three units are given in the CHARACTERISTICS section. !\
complete elementary diagram for a directional-comparison scheme over a carrier
channel including the CLPG12C may be obtained from the local district office.
Figure 2 shows typical external connections.
RATINGS
The potential coils of the CLPG12C relay are rated 120 volts intermittent and
360 volts for 10 seconds, both values being at rated frequency.
The CLPG12C relay is available in either of the following ratings at either 50
or 60 Hz.
Gl Unit
G2 Unit GD Unit GD Unit
Range Range Range Range
in in
V x I I x I
Amperes Amperes
Potential Current
Polarization Polarization
0.4 - 1.6
0.5 - 2/1
- 4
3.6 -
57.6 0.25 - 4.0
0.8 - 3.2
1 - 4/2 - 8
3.6 - 57.6
0.25
- 4.0
The angle of maximum torque is 80" ± 2" (I lags V) when the unit is potential-
polarized. If it is current-polarized, the angle of maximum torque is 10" ± 10" (I
pol lead lop).
If the unit is set for 0.25 (IxI), then the unit will pick up when VxI = 4.5 ±
15%. If a 3.6 VA pickup is required, then the control spring should be adjusted so
that the contact will just close when 3.6 VA is applied at the angle of maximum
torque.
The auxiliary-telephone-relay unit (GDIX) is available in continuous ratings
of 48 or 110 or 125 or 250 vo lts DC. The current ci rcu its are rated 3 amperes I,
cont i nuous and 140 amperes for one second. The 140 ampere rat i ng is also the
max imum permi ss ib1e current. The target-and-sea 1- in coil s with a one (1) ampere
rating will carry 30 amperes for tripping duty and 2.5 amperes continuously. The
target··and-seal-in units with ratings of 0.6 ampere DC wi 11 carry 30 amperes for
tripping duty and 0.9 amperes continuously.
CONTACTS
The tripping contacts of this relay are the normally-open contacts of the G2
and GD units. They wi 11 carry 2.5 amperes cont i nuous ly and wi 11 c1 Dse and carry 30
amperes DC for tripping duty at control voltages of 250 VDC or less. The breaker-
trip-coil circuit should, however, always be opened by a circuit-breaker auxi liary
switch or' other suitable means. If the tripping cUlTent exceeds 30 amperes, ,in
auxi liary tripping y'eliJy should be used.
,

GEI-83910
CHARACTERISTICS
OPERATING PRINCIPLES
The three main units of the CLPG12C relay are of the high-speed efficient
eight-pole cup structure. They most closely resemble an induction motor, except
that the rotor iron is stationary whi 1e the rotor conductor port i on (the cup) is
free to rotate.
PICKUP
The relays can be set to pick up, i.e. close the N.O. Contacts, at the values
of
current shown in the RATINGS section. The method of adjusting pickup is
described in the INSTALLATION PROCEDURE section.
OPERATING TIME
Figure 3 shows the operating time of the two overcurrent units (Gl and G2) as
a function of operating
current. Figure 4 shows the operating time of the
directional unit (GO) as a function of multiples of product pickup.
TABLE I
60 C.P.S. CURRENT BURDENS AT MINIMUM Gl PICKUP
MEASURED BURDENS IN
OHMS IMPEDANCE AT:
Gl Transformer
Gl
G2 Tap
R X Z 5
10
20 60
Circuit Connection Rating
Range
Ohms Ohms Ohms Amps Amps Amps
Amps
Amps Amps
Operating Shunt
0.4-1.6 0.5-2 0.80 1.84 2.00 2.00 1.80 1.50 0.95
(Studs 3-4) Shunt
0.4-1.6 1 - 4 0.60 1.36 1. 50 1.50 1.20 1.00 0.70
Stepup 0.4-1.6 0.5-2 2.44 3.42 4.20 4.20 3.10 2.20 1.20
Stepup 0.4-1.6 1 - 4 2.12 3.12 3.80 3.80 2.60 2.00 1.10
Shunt
0.8-3.2
1 - 4 0.30 0.70 0.76 0.76 0.70 0.57 0.40
Shunt 0.8-3.2 2 - 8 0.23 0.52 0.58 0.58 0.50 0.42 0.31
Stepup
0.8-3.2
1 - 4 0.73 1.04 1.26 1.26 1.20 1.05 0.75
Stepup
0.8-3.2
2 - 8 0.64 0.94 1.14 1.14 1.00 0.80 0.50
Polarizing
All All All 0.25 0.04 0.26 0.26 0.23 0.21 0.20
(Studs 5-6)
8URDEN
The burdens imposed on the current transformers are shown in Table I. The
capacitive potential circuit burden, calculated at 120 volts, 60 Hz, is shown in
the following table:
Potential Circuit Burdens
WATTS
VARS
VOLT AMPERES
18
3.18 18.35

The burdens imposed by the
for the comparable 60 Hz relays.
given in the following table:
DEVICE UNIT
Target
Seal-In
Target
Seal-In
GEI-83910
50 Hz relays are approximately 90% of those shown
The resistance of the target and seal-in units is
RATING RES. 25°C
1 A 0.34 Ohms
1 A 0.28 Ohms
0.6A 0.73 Ohms
0.6A 0.72 Ohms
___ ----.:_~ ___ :...:.... __ ---------.J
CALCULATIONS OF SEITINGS
It is
cond it ions.
follows:
not possible to give specific settings for the CLPG12C relay for all
However, a general guide for setting the three units of this relay
TWO-TERMINAL LINE
GO UNIT: Set for minimum pickup (maximum sensitivity). Check to ensure pickup for
all si ngl e-phase-to-ground fau lts on the protected 1i ne with 1ine breakers closed
at both terminals. Use dual polarization where facilities permit.
Gl UNIT: The preferred pickup setting is the minimum rated pickup value of this
unit. Do not set higher than 80% of the G2 pickup setting at the remote end of the
line. t)
G2 UNIT: Set pickup no higher than 67% of minimum single-phase-to-ground fault
current in the relay with the remote breaker closed. Lower pickup settings are
permissible, and in most cases desirable for increased speed of operation.
However, do not set pickup lower than 125% of the Gl pickup setting at the remote
end of the 1 ine.
THREE-TERMINAL LINE
GO UNIT: Set for minimum pickup (maximum sensitivity). Check to ensure pickup for
all si ngle-phase-to-ground faults on the protected 1i ne with the 1i ne breakers
closed at all three terminals. Use dual polarization where facilities permit.
Gl UNIT: The preferred pickup setting is the minimum rated pickup value of this
unit. However, when current outfeed can exist for internal faults, an attempt
should be made to set the pickup above the value of outfeeding current at that
terminal. In any event this unit should not be set higher than 40% of the G2
pickup settings at the two remote terminals.
\i~_~lnI: Set pickup no higher than 67% of the minimum single-phase-to-ground fault
current in the relay with both rl~mote line breakers closed. Lower pickup settings
are permissible, and in most Cilses desirable for increased speed of operation.
However, do not set pickup lowey' than 250% of the Gl pickup settings at the two
remote terminals.
6

GEI-8391O
CONSTRUCTION
The three main units (G1, G2, and GO) of the elPG12e relay covered by these
instructions are of the induction-cup construction.
This is the top unit of the eLPG12e relay. It has two electrically separate
contacts. The right-hand (front view) contact is closed when the unit is de-
energized. When energized, the unit operates to open its right-hand contact and
then closes its left-hand contact.
The four corner coils of the unit consist of two windings each. The inner
windings consist of a large number of turns of fine wire, and the outer windings
have a few turns of heavy wire. The inner windings are connected in series with a
capacitor to form a phase-shift i ng ci rcu it. The outer wi nd i ngs are connected in
series internally, and into the operating-current circuit externally. The four
side coils are similarly connected into the operating-current circuit.
To increase the torque output for sensitive settings of the Gl unit (1-2 times
minimum pickup), there is provided in the elPG12C relay a 2:1 autotransformer. The
transformer, when connected as a step-up transformer, effectively doubles the
current in the G1 unit.
The increased torque thus requires additional control-spring windup, thereby
i ncreas i ng the force on the norma lly-c lased (carri er-start) contact. The net
result is to reduce or eliminate the possibility of spurious carrier signals due to
shock or vibration when sensitive settings are employed on this unit.
As a further aid in reducing the possibility of spurious carrier signals, the
carrier-start contact is of the low-gradient construction.
The low-gradient contacts of the Gl unit are shown in Figure 5. Both the
stationary and the moving contact brushes are made from low-gradient material.
When subjected to vibration they tend to follow one another, thus resisting contact
separation.
The contact di a1 (A) supports the stat ionary contact brush (B) on whi ch is
mounted a conical contact tip (e). The moving-contact arm (0) supports the moving-
contact brush (E) on which is mounted a button contact tip (F). The end of the
moving-contact brush bears against the inner face of the moving-contact-brush
retainer (G). Similarly, the end of the stationary-contact brush bears against the
inner face of the stationary-contact-brush retainer (H). The stop (J), mounted on
the contact dial, functions to stop the motion of the contact arm by striking the
moving-contact-brush retainer after the moving- and stationary-contact members have
made contact. The stationary-contact support (K) and the contact dial are
assembled together by means of a mounting screw (l) and two locknuts (M).
The normally-open contact is of the standard barrel type of construction.
The barrel-type contacts shown in Figure 6 are especially constructed to
suppress bouncing. The stationary contact (G) is mounted on a flat spiral spring
(F) backed up by a thin diaphragm (e). These are both mounted in a slightly
inclined tube (A). A stainless steel ball (8) is placed in the tube before the
diaphragm is assembled. When the moving contact hits the stationary contact, the
energy of the former is imparted to the 1 atter and thence to the ball, whi cn is

GEI-83910
free to roll up the inc1 ined tube. Thus, the moving contact comes to rest with
substantially no rebound or vibration.
The moving contacts are supported on a molded plastic arm that is attached to
the rotor shaft. The arm is held from rotating freely by a control spring. This
spring maintains a torque in the
direction to hold the normally-open contacts open
by a magnitude that determines the pickup of the unit.
B. TRIP UNIT (G-2)
This is the middle unit of the CLPG relay and is similar in construction to
the Gl unit previously described. This unit has two electrically separate
contacts. The 1eft-hand contact is closed when the unit is de-energized. When
energized, the unit operates to open its 1eft-hand contact and then closes its
right-hand contact. It further differs from the Gl unit as follows: -
The Gl unit has its corner coils and side coils connected in series
internally. However, the G2 unit side- and corner-coil connections are brought out
to a tap block located at the side of the G2 unit. This tap block arrangement
permits the
G2 unit coils to be connected in series or parallel, depending on the
tap chosen. This allows the
unit to have two ranges of pickup.
Both the normally-open and normally-closed contacts of the G2 unit are of the
barre1-type construct ion previ ous1 y described. Furthermore the G2 unit does not
use
an auxiliary current transformer.
C. DIRECTIONAL UNIT (GO)
This is the bottom unit of the CLPG relay. It has 2 electrically separate
contacts of the barrel-type constructi on previous 1y described. When de-energized,
the right-hand contact
is closed. When energized in the tripping direction, the
unit operates to open the right-hand contact and then closes the left-hand contact.
The stator has eight 1 ami nated magnet ic po 1es project i ng inward and arranged
symmetrically around a
central magnetic core. The poles are fitted with current
and potential coils. Three of the corner coils are connected internally to form a
single circuit for current polarization. Each of these coils has two windings, one
of which carries the polarizing current. The other winding is connected in series
with the corresponding winding of each of the other two coils, with a capacitor.
The resultant flux from these coils is shifted in phase with respect to the
operating-circuit flux. The fourth corner coil is a potential coil for potential
polarization. The four side coils are connected together to form the operating-
current circuit.
In the annular air gap between the poles and central core is the cylindrical
cup-like part of the aluminum rotor, which turns freely in the gap. The rotor
shaft is supported at the bottom by a steel pivot that projects downward through a
bronze guide beari
ng mounted in the end of the shaft. The shaft carri es the
movable contact
arm through which the contact circuits are completed.
D. AUXILIARY UNIL.0DIX)
This unit is located in the rear of the CLPG12C relay, just below the upper
unit.

GEI-83910
It is a telephone-type relay unit with adjustable time--delay pickup. T[,e unit
is preset at thf' factory for 16-18 milliseconds time--delay pickup. f\ copper slug
on the armatli,-e end of the core delays the flux buildup, and consequently the relay
I,ickup. DrolJOut time is approximately 88 milliseconds. One normally-closed
contact and OIIC normally-open contact of the unit are brought out to separate studs
fOl" external cir'cuH control. The resistor', R?, is connected dcross the GOIX coil
when it is used on 220 or 250 VDC.
E. SEAL-IN UNIT (SI)
This unit is located in the upper right-hand corner (rear view) of the relay.
It is of the familiar hinged-armature construction and operates to lift and close
its contacts, whenever sufficient trip current flows in its operating coil.
The above units and associated components are mounted on a steel cradle
assembly that can be easily removed from the relay case.
The crad1e is locked in the case by means of 1atches at the top and bottom.
The electrical connections between the case block and cradle block are completed
through a removable connection plug. A
separate testing plug can be inserted in
p
Iace of the connecti on plug to permit test i ng the re1 ay in its case. The cover
attaches to the case from the front and includes the target reset mechanism and an
interlock arm to prevent the cover from being replaced until the connection plug
has been
inserted.
The case is suitable for either semi flush or surface mounting on panels up to
two inches (2") thick. Hardware is available for any panel thickness up to two
inches, but panel thickness must be specified on the order to ensure that the
proper hardware will be provided. Outline and panel-drilling dimensions are shown
in Figure 14.
RECEIVING, HANDLING, AND STORAGE
These re1ays, when not inc1 uded as part of a contro1 pane1, wi 11 be shi pped in
cartons designed to protect them against damage. Immediately upon receipt of a
relay, examine it for any damage sustained in transit. If injury or damage
resulting from rough handling is evident, file a damage claim at once with the
transportation company and promptly notify the nearest General Electric Sales
Office.
Reasonable care should be exercised in unpacking the relay in order that none
of the
parts are injured nor the adjustments disturbed.
If the relays are not to be installed immediately, they should be stored in
their original cartons in a place that is free from moisture, dust, and metal 1 ic
chips. Foreign matter collected on the outside of the case may find its way inside
when the cover is removed, and cause trouble in the operation of the relay.
Q

GEI-83910
ACCEPTANCE TESTS
Immediately upon receipt of the relay, an examination and tests should be made
to make sure that no damage has been sustained in shipment and that the relay
calibrations have not been disturbed. If the examination or tests indicate that
readjustment is necessary, refer to the section on SERVICING.
VISUAL INSPECTION
Check the nameplate to make sure that the model number, rating and calibration
range of the relay recei ved agree with the requ i sit ion. Remove the re1 ay from its
case and check that there are no broken or cracked molded or compound parts, and
that all screws are tight.
MECHANICAL INSPECTION
It is recommended that the following mechanical adjustments be checked:
1. There should
be no noticeable friction in the rotating structure of each unit.
The normally-closed contacts should be closed when the relay is in an upright
position.
2. There should be an end play of from .005 to .015 inch on the shafts of the
rotat i ng structures. The lower jewe l-screw beari ng of each unit should be
screwed firmly in place, and the pivot at the top of the shaft should be
locked by its set screw.
3.
The contact gap on each unit should be approximately 0.020 inches.
4.
The target shield should drop freely when the armature is pushed against the
pole piece.
With the cover fastened securely in place, check that the target
resets positively when the reset button at the bottom of the cover is
operated.
5. The armature and contacts of the seal-in unit should move freely when operated
by hand. There should be at least 1/32" wipe on the seal-in contacts.
6. Check the location of the contact brushes on the cradle and case blocks
against the internal-connection diagram for the relay (See Figure 13). Be
sure that the shorting bars are in the proper locations on the case blocks,
and that the long and short brushes on the cradle block agree with the
internal-connection diagram. Figure 8 shows a sectional view of the case and
cradl e blocks with the connecti on plug in place. Note that there is an
auxiliary brush in each position on the case block. This brush should be
formed high enough so that when the connecting plug is inserted, it engages
the
auxiliary brush before striking the main brush. This is especially
important in current circuits and other circuits with shorting bars, since an
improper adjustment of the auxiliary brush could result in a CT secondary
circuit being momentarily open-circuited.
ELECTRICAL TESTS
Upper-Unit Pick~~
Check that the green lead is connected to terminal #3 and that the black lead
is connected to terminal #3A. See internal diagram Figure 13.
10

GEI-83910
Usinq the test connections shown in Figure 9, the unit should pick up and
close the normally~~open (left) contacts <it a value of current!: 'J% of trw minimulil
',;h,wiI1 on the nameplate for thi'; unit, A neon light is Y"(;comm('nriecJ to indicttU;
contitct. CiOSIll'P, and the GD unit must be held in the normally-closed I'0.,ition Lu
obtain irldication of G1 contact closure (see Figures 9 and 13).
With the tap plugs in the lower tap range, and using the connections shown in
Figure 9, the unit should pick up (close the right-hand contacts) at a value ± 5%
of the minimum value shown on the nameplate for this unit.
Bottom-Unit Pickup (GD)
Using the test connections shown in Figure 9, the unit should pick up (close
the left-hand contacts) at 0.5 ampere ±5%.
Bottom-Unit-Core Check (GD)
a. Check the position of the notch that indicates the position of the flat on the
core. This notch should be pOinting to the front right-hand corner of the
unit, front view.
b. Short ci rcu it termi na1s 7 and 8; connect the re 1ay as shown in part A of
Figure 11.
c. Adjust 10
operate.
operate.
for 0.25 amp and Ip for 100 amps and check that the unit does not
If the unit operates, adjust the core until, the unit does not
NOTE:
DO NOT KEEP THE 100 AMPS ON THE CIRCUIT FOR MORE TIME
THAN NECESSARY, TO AVOID OVERHEATING THE COILS.
d. Open the polarizing circuit, adjust 10 for 7 amps, and check that the unit
does not operate. If the unit operates, adjust the core for no operation and
repeat the test, starting at b.
e. Unshort terminals 7 and 8 and connect as shown in part B of Figure 11.
f. Set 10 for 0.25 amperes and Vp for 120 volts, and check that the unit does not
operate. If the unit operates, adjust the core for no operation and repeat
the tests, starting at b.
GD1X Unit Pickup
USing the test connections shown in Figure 10, the unit should pick up at a
value of 80% or less of the voltage shown on the nameplate. The G1 normally-open
contact must be held closed during this test (see Figures 10 and 13).
11

GEI-83910
INSTALLATION PROCEDURE
If after the ACCEPTANCE TESTS the relay is held in storage before shipment to
the job site, it is recommended that the visual and mechanical inspection described
under the
section on ACCEPTANCE TESTS be repeated before instanation.
Before any of the following electrical adjustments are made, the relay should
be in its case, preferably mounted in its permanent location.
RELAY SETTINGS
Refer to the section on CALCULATIONS OF SETTINGS for a discussion of suggested
procedures for determining the
settings of the three main units.
CARRIER-PICKUP-START UNIT (GIl
If the required setting is less than two times the mlnlmum value shown on the
namep 1 ate, the Gl aux il iary current transformer shou 1d be connected in such a way
as to step up (The green lead connected to terminal #3 and the black lead connected
to terminal #3A). Should the required setting be greater than two times the
minimum value shown on the nameplate, interchange the green and black leads. Using
the test connections shown in Figure 9, apply the desired current to the relay.
Loosen the hexagonal locking screw located at the rear of the spiral-spring
assembly. Then slip the adjusting ring (to which the control spring is attached)
in the ring guide in a direction that will cause the normally-open contacts barely
to close at the pickup level chosen. Retighten the locking screw and recheck the
settings.
CLUTCH ADJUSTMENT
USing the test connections shown in Figure 9, and referring to Table II, check
that the clutch slips (i.e. the induction cup begins to rotate after the normally-
open contact
has closed) within the prescri bed 1 imits. To prevent overheati ng the
relay, a suggested method for determining that the clutch slips within the
prescribed
limits is to apply current 5% below the minimum shown in the table and
note that the clutch does not slip. Next apply current 5% above the maximum shown
in the table and note that the clutch does slip.
Unit
Gl t
G2
GO
TABLE II
CLUTCH ADJUSTMENTS
Current Rating, Amps
0.4 - 1.6
0.8 3.2
0.5 2.0
1.0 4.0
0.25 4.0
Product Pickup
Clutch
Slips, Amps
3.5 - 5.0
7.0 -10.0
7.5 -10.0
15.0 -20.0
10.0 -15.0
t Values of clutch slip are primary amperes with the auxiliary
current transformer not connected for step up.
12

GEI-83910
TRIP UNIT (G2)
Pickup: Connect the taps in the G2 tap block so that the desired setting will be
within the selected tap range. Should the desired setting be such that either tap
range
would be adequate, it is recommended that the lower tap range be used on two-
terminal lines and the higher tap range be used on three-terminal lines. Using the
test connections shown in Figure 9, apply the desired level of current to the relay
and set pickup by means of the control-spring adjustment, as previously described
for the G1 unit.
G2 Unit Rebound Test:
Connect the relay as shown in Figure 7, and check that the G2-unit contact
wi 11 not rebound on the removal of an external fault. The test connections show
the TB unit of the NAA22A being used for this test but if an instantaneous dropout
relay is available it may be substituted. The use of the TB unit will result in
loss of instantaneous reclosure in the
carri er-current scheme, and the TB unit
contact in
circuit 15-16 must be shorted so that protection is still provided.
The following test procedure should be followed.
1. Close the
G2 unit manually to check that the lamp will light.
2. Manually close the TB unit and apply maximum expected through-fault
current
to the G2 unit.
3. Remove the current and check that the lamp does not light.
CAUTION: It is advisable to practice this sequence, so that the tester will be
able to operate it correctly with a high-current impulse short enough
to avoid overheating the unit.
If the G2 unit fails this test, check the wipe and gap of the G2 barrel contacts,
and also the clutch slip adjustment.
CLUTCH ADJUSTMENT
Using the test connections shown in Figure 9 and the appropriate value shown
in Table II, check the clutch adjustment as previously described for the Gl unit.
DIRECTIONAL UNIT (GO)
Current-Polarized Pickup: Using the test connections shown in Figure 9, apply
the desired level of current to the relay
and set pickup by means of the control-
spring adjustment,
as previously described for the G1 unit. The product pickup
thus obtained will
be the square of the current app 1i ed to the relay. Thus, if a
product pickup of 0.25
ampere is desired, 0.5 ampere should be applied to the
relay.
Potential-Polarized Pickup: Using the test connections shown in Figure 12, the
GO unit can be set for potential polarization. When setting pickup for potential
polarization, it is recommended that a voltage (Vp) of 5 to 30 volts be used. Five
volts is the minimum value encountered in ground relaying, while above 30 volts the
current
is small and difficult to measure.
Clutch Adjustment: Using the test connections shown in Figure 9 and the
appropriate value
from Table II, the clutch may now be set as previously described
for the G1 unit.
13

GEI-83910
GDIX Unit Pickup: Using the test connections shown in Figure 10, the unit
should pick up at 80% or less of the DC voltage shown on the nameplate. With rated
voltage suddenly
applied, the unit should pick up in 16-18 milliseconds.
PERIODIC CHECKS AND ROUTINE MAINTENANCE
In vi ew of the vital role of protecti ve re1 ays in the operati on of a power
system it is important that a periodic test program be followed. It is recognized
that the interva1 between periodi c checks wi 11 vary dependi ng upon envi ronment,
type of
relay, and the user's experience with periodic testing. Until the user has
accumulated enough experience to select the test interval best suited to his
individual requirements
it is suggested that the following points be checked once a
year.
MECHANICAL CHECKS
Operate the contacts by hand and check that the contacts are making with
proper wipe.
The barrel-type contacts are marked with a letter on the rear of the
barrel that designates the amount of wipe.
Unit Contact Stamping
Wipe
Top
Left H .013-.018
Middle Left L .002-.004
Middle Right L .002-.004
Bottom
Right L .002-.004
Bottom
Left S .004-.009
The wipe is the distance the spiral contact can move into the barrel before it
hits the diaphragm, as shown in Figure 6. This can be changed by adjusting the
flat spiral spring until the proper spacing is obtained.
Examine the contact surfaces for signs of tarnishing or corrosion. Fine
silver contacts should be cleaned with a burnishing tool that consists of a
flexible strip of metal with an etch-roughened surface. Burnishing tools designed
especially for cleaning relay contacts can be obtained from the factory. Do not
use knives,
files, abrasive paper or cloth of any kind to clean relay contacts.
When burnishing the low-gradient G1 unit contacts, exercise additional caution
to avoid
damaging the delicate leaf springs to which the contacts are fastened.
ELECTRICAL TESTS
Connect the relay as shown in Figure 9 and check that the pi ckup of the G1
unit is within ±5% of the original setting. Next check that the clutch setting is
within ±5% of the original setting. Repeat the tests for the G2 and GO units,
using the test diagrams as shown in Figure 9.
Connect the relay as shown in Figure 10 and check that the pickup of the GD1X
unit is within ±5% of the original pickup voltage.
14

GEI-83910
SERVICING
If any of the mechanical or electrical check points described in the previous
sections are
found to be out of limits, the following points should be observed in
restoring them.
MECHANICAL ADJUSTMENTS
1. Gl-unit low-gradient (right-hand) contact adjustment:
a.
With the relay setting upright, and the moving contact held away from the
stationary contact, both the stationary-contact brush and the moving-
contact brush should touch their respective retainers (See Figure 5).
b. With the relay lying on its right side and the moving contact held clear,
the stationary-contact brush should just part from its retainer under its
own weight.
c. With the relay lying on its left side and the moving contact held clear,
the moving-contact brush should just part from its retainer under its own
weight.
d.
With the relay vertical and de-energized, the contacts should make with
(0.003-0.005 inch) deflection on each brush from its own retainer. To
adjust the contact wipe proceed as follows:
Adjust the stop screw in the face of the
stationary contact so that the
contact
tips just separate, and then back it off 1/2 turn.
e. The gap on the normally-open contact should be between 15 and 20 mils,
which can be achieved as follows:
Adjust the
left contact barrel until the contacts just part, and then back
the barrel off 1/2 to 2/3 of a turn.
2. G2-unit contact adjustment.
a. With the unit completely de-energized, adjust the control spring so that
the center line of the moving contact arm is parallel to the sides of the
relay.
b. Using a neon light as an indication of contact closure, turn both contact
barrels into the moving contact until they just touch.
c. Lock the left barrel in place by means of the clamping screw.
d. Rotate the
right barrel approximately 210· to obtain the 0.015-0.020 gap.
e. Lock the right barrel in place.
3. GO-unit contact adjustment.
a.
The GD unit adjustment is similar to the G2 unit previously described,
except the right barrel is locked in place and the left barrel is rotated
to obtain the 0.015-0.020 inch contact gap.
15

GEI-83910
4. Shaft End Play: The end play of the shafts of the three main units should be
1/64". This can be adjusted by the position of the upper pivot. Be sure to
tighten the set screw that holds the upper pivot in position after the
adjustment is completed.
5. Barrel Contact Wipe Check and Adjustment: To check for the proper amount of
contact wipe, first loosen the screw that locks the barrel contact in its
mounti ng block so that the barrel contact can be threaded in and out. Next
hold the moving contact still. In the top unit, do this by using the stop
screw of the low-gradient contact. In the middle and bottom units, do this by
pushing the moving contact against the other barrel. Now thread the barrel
contact until its silver contact tip just touches the moving contact. Use a
neon 1i ght as an i nd i cat i on of contact closure. Conti nue to thread the
contact barrel until the back of the contact touches the diaphragm behind it
(See Figure 6) The point at which this occurs can only be determined by feel.
CAUTION: Do not thread the barrel past the point where the contact first touches
the diaphragm; further threading of the barrel could damage the diaphragm.
The number
of degrees of contact barrel rotation between when the silver
contact tip just touches the moving contact and when the back of the contact
touches the di aphragm behi nd it determi nes the contact wipe. Rotating the
barrel 45° corresponds to a 0.004 wipe, while 105° corresponds to a 0.009
wipe.
If the proper wipe is not noted, then the spiral spring upon which the contact
tip is fastened must be re-formed. Remove the contact barrel from the
mounti ng block and remove the threaded cap. Lift off the spi ra 1 contact
assembly. Holding the outer edge of the spiral with your fingers, place a
tweezer on the inside of the spiral next to the contact cone. If more wipe is
reqUired, then lift the inside spiral so that the contact tip is stretched
away from the diaphragm. If less wipe is required, then the spiral should be
stretched so as to move the contact tip toward the diaphragm. Make sure that
the spiral is not distorted or bent during this process. Replace the spiral
contact assembly on the barrel and screw the cap onto the barrel. The wi pe
should now be re-checked by following the above procedure. It may be
necessary to repeat the wipe adjustment until the proper wipe is obtained.
To finish the procedure. set the proper contact gap.
ELECTRICAL ADJUSTMENTS
Clutch Adjustment: The clutch is adjusted by means of the screw located on
the right-hand side of the moving support. See Figure 1 for location of this
screw. To readjust the clutch, first loosen the hexagonal locking nut on the
adjusti ng screw. Turni ng the screw into the shaft (cl ockwi se rotati on of the
screw) increases the value of current necessary to cause the clutch to slip. On
the G2 unit it is recommended that the clutch adjustment be made with the taps in
the lower tap range.
GDIX Pickup: To change the pickup time or voltage of the GDIX unit, resistor
Rl is adjusted (see Figure IB). Increasing Rl will increase the pickup voltage and
pickup time. Be certain the slide band on Rl is retightened after this adjustment,
but do not overtighten, to avoid damaging the resistance wire.
16

GEI-83910
RENEWAL PARTS
It is recommended that suffi cient quantit ies of renewal parts be carri ed in
stock to enable the
prompt replacement of any that are worn, broken, or damaged.
When orderi ng renewal parts, address the nearest sales office of the General
Electric Company, and specify the quantity required, the name of the part, and
complete relay nameplate data. If possible, give the General Electric Company
requisition number on which the relay was furnished.
LIST OF FIGURES
Figure
lA
(8029723)
CLPG12C
Relay Front View
Figure
IB
(8029724 )
CLPG12C Relay Rear View
Figure 2
(362A544-2)
External Connections for the
CLPG12C Relay
Figure 3
(0891B0495)
Time-Current Curves for the Overcurrent Units of the
CLPG12C Relay
Figure 4
(0891B0496)
Contact-Closing Time-Curves for the Directional Unit
of
the CLPG12C Relay
Figure 5
(8027688 & 8023399)
Low-Gradient Contact Assembly for
the Gl
Figure 6 (6077069-4)
Figure 7 (459A215)
Figure 8 (8025039)
Figure 9 (0148A4066)
(Carrier-Start) Unit
Barrel-Type Contact
Assembly for CLPG12C Relay
Test Connections
to Check for G2 Rebound Using the
Carrier-Current Auxiliary
Cross Section of Drawout Case Showing Position of
Auxiliary
Brush and Shorting Bar
Test Connections for Checking Gl, G2 and GD Unit
(Current-Polarized) Pickup and Clutch Settings
Figure 10 (0148A4065) Test Connections for Checking GDIX Time and Pickup
Voltage
Figure
11 (0459A0204) Test Connections for Checking Proper Directional-Unit
Core Position
Figure 12 (0148A4064) Test Connections for Setting GD Unit Pickup Using
Potential Polarization
Figure 13 (0148A3975-3) Internal Connections (Front View) for CLPG12C Relay
Figure 14 (6209276-3) Outline and Panel-Drilling Dimensions for CLPG12C Relay
Since the last edition, changes have been made in the INSTALLATION PROCEDURE G2
Unit Rebound Test, the SERVICING Barrel Contact Wipe Check and Adjustment, and
Figure 14.
17

Gl i --B391O
(il UhJll
G2 UNIT
GO UNIT
f: ,i
'~;, "\': I! ,.1-,
I G'N Gf~I\.~iir:'rT
C.'Jil! [ fie
G2 JNIT
TAP BLOCK
CLUTCH
ADJUSTING
SCREW
8ARREL
CONTACT
Figure lA (8029723) CLPG12C Relay Front View
2: I AUXILIARy
CURRENT
TRANSFORMER
SEAL IN
UNIT
ADJUSTA6LE
REACTOR
GDIX UNIT
THYRITE.
TRANSfORMER
THrRITE
STACK
RI
LEAD
Figure 18 (8029724) CLPG12C Relay Rear View
18

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GEl-839ID
A-C BUS
LA...
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6
~~AUX
<
67N
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( 5
CON
CONNECTIONS
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2
3
N
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. P T'S
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AR I Z I N G.
FOR CURRENT
7 67N
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GO
8
POL
CON
CURRENT
ARIZfD,OMIT
MS. TO AUX.
.PT I
JUM
no
II
PHASE
REL AY
ON 67N ON
G~D AG2f1-1
I
v- l(-
v 3
DEV I CE FUNCT I ON NUMBERS
52-CIRCUIT BREAKER
67N-CARR I ER CURRENT GROUND
RELAY TYPE ClPG
G2-0VERCURRENT UNIT
G I-OVERCURRENT UN I T BLOCK I NG
GD-D I RECT I ONAL UN I T
S. &CONNECT A
PER FROM STUD
STUD 8.
Figure 2 (362A544 [4]) External Connections for the CLPG12C Relay
1q

Glf-B3910
-- -
1-+++-I-+---+-l--1--1+1+l-+-++1-l--+-+-H -H-iLHf--HH+-i-+-i++-+-H-
r
,~~hH--~-+-+~~H-~~~--~+-~+H-~~~--+-+~~+H-++~+-~-'-+--+-'~~+-~++1' ~
I "'
W--l-iI-W __ --l----l---+--+-W-W--W-U..l--- __ I--+-W-LW_1-L1-U __ -L_.-1---LUDl-~__l_UI__I_1 _ _1_1_l .._ -LL"+t-ti :;
A-G2 Contact Closing Time-Maximum Pickup
B-GI Cantacf Opening Time-Maximum P1ckup
C-
G2 Contoc! Closlno Time- Minimum Pickup
0- GI Contact Openin9 TIme- Minimum Pickup =
-
Notes' _
I. All Curves Token with Maximum Recommended -
Clu tch Settin91 _
2. AS B Taken with Auxiliary Transformer
I I Connected In Shunt (No Step up)
't~rrlr~~I~~tEEEtj~~~~~~~1.~3~.~C~S:D::T::ak~e~n~w:i~th::A:U:X~11:la~r~y-~T~ra~n~.:f~o~r,m~e~r,
" Connected tor Step Up
..
,
5 r- _. _ -,
" j--- -H
- - i
--
'Itmiil1t~Iii§' emmf~=1= T r
• 4
1++-++(.---'--- ---1---+-+-+-1--l+-I--I-++1-l---l--l--l-I-I-l+ -- -H-1+--+
1
+-t- +-l if- -i
,1-++++I---+--I--l-I--W-W-I-I--i--W----'--l--J.-l-f+H--+-W-W---+-l--t-H+l+I-++++--+-
i
--; 1- 1i
---'--1l-W-l---I---I--I-++~-l+-I--t - --I -i- .- .--
,LJ-LLLL.--+--1-1-LLlLLJ_LLLL __ L.~1-LLLLLJ.LUJ __ -L-1--+-.LLlLL~.LUL
~! 1,'.'1 lG 4lI SC10701(lte~ ~ ~ ~ ~ ~~~~~
MUL TIPLES OF PICKUP SETTING
Figure 3 (089180495) Time-Current Curves for the Overcurrent Units
of the
CLPG12C Relay
z
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•
•
,
•
.,
..
..
t.