GE MFAC 14 User manual

GE Energy Connections
Grid Solutions
MFAC
14, 34
User Manual
High Impedance Differential Relay
Publication reference: R8007H

HANDLING OF ELECTRONIC EQUIPMENT
A person’s normal movements can easily generate electrostatic potentials of several
thousand volts. Discharge of these voltages into semiconductor devices when
handling circuits can cause serious damage, which often may not be immediately
apparent but the reliability of the circuit will have been reduced.
The electronic circuits of General Electric products are immune to the relevant
levels of electrostatic discharge when housed in their cases. Do not expose them
to the risk of damage by withdrawing modules unnecessarily.
Each module incorporates the highest practicable protection for its semiconductor
devices. However, if it becomes necessary to withdraw a module, the following
precautions should be taken to preserve the high reliability and long life for which
the equipment has been designed and manufactured.
1. Before removing a module, ensure that you are a same electrostatic
potential as the equipment by touching the case.
2. Handle the module by its front-plate, frame, or edges of the printed circuit
board. Avoid touching the electronic components, printed circuit track or
connectors.
3. Do not pass the module to any person without first ensuring that you are both
at the same electrostatic potential. Shaking hands achieves equipotential.
4. Place the module on an antistatic surface, or on a conducting surface which is
at the same potential as yourself.
5. Store or transport the module in a conductive bag.
More information on safe working procedures for all electronic equipment can be
found in BS5783 and IEC 60147-0F.
If you are making measurements on the internal electronic circuitry of an
equipment in service, it is preferable that you are earthed to the case with a
conductive wrist strap.
Wrist straps should have a resistance to ground between 500k – 10M ohms. If a
wrist strap is not available you should maintain regular contact with the case to
prevent the build up of static. Instrumentation which may be used for making
measurements should be earthed to the case whenever possible.
General Electric strongly recommends that detailed investigations on the electronic
circuitry, or modification work, should be carried out in a Special Handling Area such
as described in BS5783 or IEC 60147-0F.

TYPES: MFAC 14
MFAC 34
CONTENTS
SAFETY SECTION 5
1. INSTALLATION 9
1.1 General
9
1.2 Unpacking
9
1.3 Storage
9
1.4 Site
9
2. COMMISSIONING 10
2.1 Description of relay, calculation of setting and
commissioning preliminaries 10
2.2
Instructions to ensure that the relay can be commissioned at the specific settings
for the application
12
3. MAINTENANCE 18
4. MECHANICAL SETTINGS 18
4.1 General
18
4.2 Contact settings
18
4.3 Mechanical flag settings
18
5. PROBLEM ANALYSIS 19
5.1 Failure to operate
19
5.2 Output contacts not changing state
19
6. SPARES 20
7. COMMISSIONING TEST RECORD 21
REPAIR FORM 23
4

1. SAFETY SECTION
This Safety Section should be read before commencing any work on the
equipment.
1.1 Health and safety
The information in the Safety Section of the product documentation is intended to
ensure that products are properly installed and handled in order to maintain them in a
safe condition. It is assumed that everyone who will be associated with the
equipment will be familiar with the contents of the Safety Section
.
1.2 Explanatio n of sy mbo l s and labels
The meaning of symbols and labels may be used on the equipment or in the product
documentation, is given below.
Cauti o n : refer to product documentation Cauti o n : risk of electric shock
Protective/safety *earth terminal Functional *earth terminal
Note: This symbol may also be
used for a protective/safety earth
terminal if that terminal is part of a
terminal block or sub-assembly
e.g. power supply.
*NOTE: THE TERM EARTH USED THROUGHOUT THE PRODUCT DOCUMENTATION IS
THE DIRECT EQUIVALENT OF THE NORTH AMERICAN TERM GROUND.
2. INSTALLIN G , COMMISSIONING AND SERVICIN G
Equip m ent connections
Personnel undertaking installation, commissioning or servicing work on this
equipment should be aware of the correct working procedures to ensure safety. The
product documentation should be consulted before installing, commissioning or
servicing the equipment.
Terminals exposed during installation, commissioning and maintenance may present
a hazardous voltage unless the equipment is electrically isolated.
If there is unlocked access to the rear of the equipment, care should be taken by all
personnel to avoid electrical shock or energy hazards.

Voltage and current connections should be made using insulated crimp
terminations to ensure that terminal block insulation requirements are maintained for
safety. To ensure that wires are correctly terminated, the correct crimp terminal and
tool for the wire size should be used.
Before energising the equipment it must be earthed using the protective
earth terminal, or the appropriate termination of the supply plug in the case of plug
connected equipment. Omitting or disconnecting the equipment earth may cause a
safety hazard.
The recommended minimum earth wire size is 2.5mm2, unless otherwise stated in
the technical data section of the product documentation.
Before energising the equipment, the following should be
checked:
−Voltage rating and polarity;
−CT circuit rating and integrity of connections;
−Protective fuse rating;
− Integrity of earth connection (where applicable)
− Remove front plate plastic film protection
− Remove insulating strip from battery compartment
3.
EQUIPMENT OPERATING CONDITIONS
The equipment should be operated within the specified electrical and environmental
limits.
3.1
Current transformer circuits
Do not open the secondary circuit of a live CT since the high level voltage produced
may be lethal to personnel and could damage insulation.
3.2
External r e sist ors
Where external resistors are fitted to relays, these may present a risk of electric
shock or burns, if touched.
3.3
Battery replacement
Where internal batteries are fitted they should be replaced with the
recommended type and be installed with the correct polarity, to avoid possible
damage to the equipment.
3.4
Insulation and dielectric strength testing
Insulation testing may leave capacitors charged up to a hazardous voltage. At
the end of each part of the test, the voltage should be gradually reduced to zero, to
discharge capacitors, before the test leads are disconnected.
3.5
Insertion of modules and pcb cards
These must not be inserted into or withdrawn from equipment whist it is
energised since this may result in damage.

3.6
Fibre optic communica t ion
Where fibre optic communication devices are fitted, these should not be
viewed directly. Optical power meters should be used to determine the operation
or signal level of the device.
4. OLDER
PRODUCTS
Electrical adjustments
Equipments which require direct physical ad ustments to their operating
mechanism to change current or voltage settings, should have the electrical
power removed before making the change, to avoid any risk of electrical shock.
Mechanical adjustments
The electrical power to the relay contacts should be removed before checking any
mechanical settings, to avoid any risk of electric shock.
Draw out case relays
Removal of the cover on equipment incorporating electromechanical operating
elements, may expose hazardous live parts such as relay contacts.
Insertion and withdrawal of extender cards
When using an extender card, this should not be inserted or withdrawn from the
equipment whilst it is energised. This is to avoid possible shock or damage
hazards. Hazardous live voltages may be accessible on the extender card.
Insertion and withdrawal of heavy current test
plugs
When using a heavy current test plug, CT shorting links must be in place before
insertion or removal, to avoid potentially lethal voltages.
5.
DECOMMISSIONING AND DISP OSAL
Decommissioning: The auxiliary supply circuit in the relay may include
capacitors across the supply or to earth. To avoid electric
shock or energy hazards, after completely isolating the supplies
to the relay (both poles of any dc supply), the capacitors should
be safely discharged via the external terminals prior to
decommissioning.
Disposal: It is recommended that incineration and disposal to
water courses is avoided. The product should be disposed of in
a safe manner. Any products containing batteries should have
them removed before disposal, taking precautions to avoid
short circuits. Particular regulations within the country of
operation, may apply to the disposal of lithium batteries.

6.
TECHNICAL SPECIFI C ATIONS
Protective fuse rating
The recommended maximum rating of the external protective fuse for this
equipment is 16A, Red Spot type or equivalent, unless otherwise stated in the
technical data section of the product documentation.
Insulation class: IEC 601010-1 : 1990/A2 : 2001
Class
I
EN 61010-1: 2001
Class
I
This equipment requires
a protective (safety) earth
connection to ensure
user safety.
Insulation
Category
(Overvoltag e ):
IEC 601010-1 : 1990/A2 : 1995
Category III
EN 61010-1: 2001
Category III
Distribution level, fixed
insulation. Equipment in this
category is qualification
tested at 5kV peak,
1.2/50 µ s,
500Ω, 0.5J, between all supply
circuits and earth and also
between independent circuits.
Environment: IEC 601010-1 : 1990/A2 : 1995
Pollution degree 2
EN 61010-1: 2001
Pollution degree 2
Compliance is demonstrated
by reference to generic
safety standards.
Product Safety: 72/23/EEC
EN 61010-1: 2001
EN 60950-1: 2002
Compliance with the
European Commission Low
Voltage Directive.
Compliance is demonstrated
by reference to generic
safety standards.

Section 1. INSTALLATION
1.1 General
Protective relays, although generally of robust construction, require careful
treatment prior to installation and a wise selection of site. By observing a few
simple rules the possibility of premature failure is eliminated and a high
degree of performance can be expected.
The relays are either despatched individually or as part of a panel/rack
mounted assembly in cartons specifically designed to protect them from
damage.
Relays should be examined immediately they are received to ensure that
no damage has been sustained in transit. If damage due to rough
handling is evident, a claim should be made immediately to the transport
company concerned and the nearest General Electric representative should be
promptly notified. Relays which are supplied unmounted and not intended for
immediate installation should be returned to their protective polythene bags.
1.2 Unpacking
Care must be taken when unpacking and installing the relays so that none
of the parts are damaged or their settings altered and must at all times be
handled by skilled persons only.
Relays should be examined for any wedges, clamps, or rubber bands
necessary to secure moving parts to prevent damage during transit and these
should be removed after installation and before commissioning.
Relays which have been removed from their cases should not be left in
situations where they are exposed to dust or damp. This particularly
applies to installations which are being carried out at the same time as
constructional work.
1.3 Storage
If relays are not installed immediately upon receipt they should be stored in a
place free from dust and moisture in their original cartons and where de-
humidifier bags have been included in the packing they should be retained.
The action of the de-humidifier crystals will be impaired if the bag has been
exposed to damp ambient conditions and may be restored by gently heating
the bag for about an hour, prior to replacing it in the carton.
Dust which collects on a carton may, on subsequent unpacking, find its way
into the relay; in damp conditions the carton and packing may become
impregnated with moisture and the de-humidifying agent will lose its efficiency.
The storage temperature range is –25° and +70°C.
1.4 Site
The installation should be clean, dry and reasonably free from dust and
excessive vibration. The site should preferably be well illuminated to facilitate
inspection.
An outline diagram is normally supplied showing panel cut-outs and hole
centres. For individually mounted relays these dimensions will also be found in
Publication R6008.
Publication R7012 is a Parts Catalogue and Assembly Instructions. This
document will be useful when individual relays are to be assembled as a
composite rack or panel mounted assembly.
9

Publication R6001 is a leaflet on the modular integrated drawout system of
protective relays.
Publication R6014 is a list of
recommended suppliers for the pre-
insulated connectors.
Section 2. COMMISSIONING
2.1 Description of relay, calculation of setting and commissioning preliminaries
2.1.1 Descriptionof MFAC 14/MFAC
34
This is a voltage operated relay having seven equally spaced settings of
15–185 volts, 25–175 volts, 25–375 volts or 100–400 volts which may be selected
by meansof a plug bridge.
The relays may be used for any type of high impedance circulating
current protection.
2.1.2 Listof abbreviations.
IE
= Current transformer exciting currentat relay setting voltage (referred to the
CT secondary current)
IF
= Maximum value of primary through fault currentfor which protection must
remainstable.
IFM
= Maximum value of primary fault current for internalfault.
IP
= Primary currentfor operation of protection.
IR
= Relay operating current.
ISH
= Current in shunt resistor at relay setting V
R
.
N = Turns ratio of currenttransformer.
n
= No. of current transformers in parallel with relay.
RCT = Secondary resistance of currenttransformer.
RL
= Lead resistance between furthest current transformer and relay
connection point.
RR
= Relay impedance.
RSH
= Value of shunt resistor.
VF
= The theoretical voltage which would be produced across the relay circuit
under internalfault condition.
VF
= IFM (RCT + 2RL +
R
R
) N
VK
= Knee point voltage of currenttransformer.
VP
= Peak voltage across relay circuit under maximum internalfault conditions.
VS
= Minimum setting voltage. (calculated)
VR
= Relay setting voltage.
2.1.3 Calculationof relay setting.
The
minimum setting voltage to ensure stability is
VS ≥
IF (RCT + 2RL)
N
The relay plug setting voltage VR
must be set to the nearest tap above V
S
.
10

The minimum knee point voltage must be
VK ≥
2V
R
The operating current of the relay is 38mA, irrespective of tap selected, excluding
the current drawn by the external metrosil. When a standard
metrosil is included
with the relay, the relay operating current including the
metrosil is given in the table
below.
It
must be appreciated that metrosils have large tolerances and these figures
are given for guidance only.
a) Low range relay (5V steps)
Setting voltage V
R
15 50 75 100 125 150 175 185
Relay current I
R
(mA)
38
38
39
42
46
55
72 81
(including metrosil, C = 450)
b) Low range relay
Setting voltage V
R
25 50 75 100 125 150 175
Relay current I
R
(mA)
19
19
20
23
27
36
53
(including metrosil, C = 450)
c) High range relay
Setting voltage V
R
25 75 125 175 225 275 325
Relay current I
R
(mA)
19
19
20
22
24
31
44
(including metrosil, C = 900)
d) 100–400V version
Setting voltage V
R
100 150 200 250 300 350 400
Setting voltage IR(mA)
19
19
20
20
23
27
36
(including metrosil, C = 1100)
The primary current for operation is given by
IP
= N (IR + n I
E
)
If the
resultant value of IP is too low it may be increased by the addition of a
shunt resistor RSH to give a currentof
ISH
= V
R
R
SH
The new increased value of primary current
IP
= N (IR + nIE + I
SH
)
External metrosils.
Each FAC relay is applied with an external
metrosil which must be wired across
the relay circuit. This provides a
shunt circuit for high internal fault currents and
prevents a high voltage being developed across the CT and relay circuits.
2.1.4 Commissioning preliminaries.
Inspection.
Carefully examine the module and case to see that no damage has occurred
during transit. Check that the relay serial number on the module, case and cover
are identical, and that the model number and rating information are correct.
Carefully remove any elastic bands/packing fitted for transportation purposes.
Carefully actuate the armature of each unit in turn with a small screwdriver/probe.
Note that immediately after the point where any normally open contacts just make
11

there is a small further movement of the armature. This ensuresthat contact follow
through and wiping action is present. On unitsfitted with hand reset flag indicators,
check the flag is free to fall before, or just as, any normallyopen contacts touch.
Check that the external wiring is correct to the relevant relay diagram or
scheme diagram. The relay diagram
number appears inside the case.
Particularattentionshouldbe paid to the correct wiring and value of any external
resistors indicated on the wiring diagram/relay rating information.
Note that shortingswitches shown on the relay diagram are fitted internally
across the relevant case
terminals and close when the moduleis withdrawn. It is
essential that such switches are fitted across all CT circuits.
If a test block type MMLG is provided, the connections shouldbe checked to the
schemediagram, particularly that the supply connections are to the ‘live’ side of the
test block (colouredorange) and with
terminals allocated with odd numbers (1, 3, 5,
7, etc.).
Earthing.
Ensure that the case earthing connection above the rear
terminal block, is used
to connect the relay to a local earth bar.
Insulation.
The relay, and its associated wiring, may be insulationtested between:
a) all electrically isolated circuits
b) all circuits and earth
An electronic or brushless insulation tester should be used, having a dc voltage
not exceeding 1000V. Accessible
terminals of the same circuit should first be
strapped together.
Deliberate circuit earthing links, removed for the tests, must subsequently be
replaced. Terminal allocation.
Terminals of the relay are normally allocated as below, but reference should
always be made to the relevant diagram.
a) Single pole relays
Normally open contacts 1, 3 and 2,
4.
AC currentinput – 27, 28.
An alternative version of the relay has additional normallyopen contacts
connected to 5, 7 and 6,
8.
b) Triple pole relays
Normally open contacts 1, 3 and 2,
4.
The contacts are normallyconnected in parallel for the three phases but
a version of the relay having contacts broughtout separately is available.
AC currentinputs
- 23, 24 : 25, 26 : 27, 28.
2.2 Instructions to ensure that the relay can be commissioned at the specific
settings for the application
It is only necessary to check the relay at the setting on which it is to be used.
The relay
must not be used at any setting other than that for which the setting has
been calculated.
12

2.2.1 Test equipment required
1 – Secondary injection test
equipment capable of providing an ac voltage
supply of up to at least 120% of the relay setting.
1 – Multifinger test plug type MMLB 01 for use with test block type MMLG if fitted.
1 – Miniature split plug type MMLB 03 to fit relay plug bridge.
3 – Calibrated
multimeters 0–10 amp ac, 0–400 volt ac.
1 – Set primary injection testing equipment.
2.2.2 General
If the relay is wired
through an MMLG test block it is recommended that all
secondary injection tests shouldbe carried out using this block.
Ensure that the main system current
transformers are shortedbefore isolating the
relay fromthe current
transformers in preparation for secondary injection tests.
DANGER:
DO NOT OPEN CIRCUIT THE SECONDARY CIRCUIT OF A CURRENT
TRANSFORMER SINCE THE HIGH VOLTAGE PRODUCED MAY BE LETHAL
AND COULD DAMAGE INSULATION.
When type MMLG test block facilities are installed, it is
important that the sockets in
the type MMLB 01 test plug, which correspond to the current
transformer secondary
windings, are LINKED BEFORE THE TEST PLUGIS INSERTED INTO THE TEST
BLOCK. Similarly, a MMLB 02 single finger test plug
must be terminated with an
ammeter BEFORE IT IS INSERTED to
monitor CT secondary currents.
It is assumedthat the initial preliminary checks have been carried out.
2.2.3 Relay CT shortingswitches
With the relay removed fromits case, check electrically that the CT shortingswitch
is closed.
2.2.4 Secondary injection testing
Connect the circuit as shown in Figure 1 and ensure that the currenttransformer
primary is open circuit and that if any earthing connections are fitted, they do not
shortout the primaries of any current transformers.
Increase the voltage untilthe relay just operates.
Note the current in the relay (this can be done using the
miniature split plug
inserted into the appropriate position of the plug bridge connected to an
ammeter).
It should be approximately 38mA at setting.
Note also the voltage at which the relay operates which shouldcorrespond to the
setting VR of the relay with a tolerance of ±10%. The total secondary currentfor
operation will be given on ammeter
A1. This test shouldbe repeated for each pole
of the
relay.
Drop off/Pick up ratio.
Check that this ratio is greater than
50%.
13

2.2.5 Primary injection testing
It is essential that primary injection testing is carried out to prove the correct
polarity of currenttransformers.
Before
commencing any primary injection testing it is essential to ensurethat the
circuit is dead, isolated fromthe
remainder of the system and that only those
earth connections associated with the primary test
equipment are in position.
2.2.6 Primary fault setting
The primary fault setting of any balanced schemecan be checked using the circuit
shown in Figure 2. The primary currentis injected into each current
transformer in
turnand increased untilthe relay operates. The voltage at which the relay
operates shouldbe within ±10% of the relay setting voltage VR. The primary
currentfor operation and relay currentshouldbe noted.
In the case of machineprotection similartests
must be carried out by injecting
first into each current
transformer in turnto determinethe primary fault setting.
For large machinesthe machineitself can be used to provide the fault currentto
check the primary fault setting as shown in Figure 5. The machineshouldbe run
up to speed with no excitation. The excitation shouldthen be increased untilthe
relays have all operated. The primary current,relay current and relay voltage
shouldbe noted as each relay operates.
2.2.7
Through fault stability
With any form of unbalanced protection it is necessary to check that the current
transformers are correctly connected. For this purpose with a restricted earth
fault scheme the circuit shown in Figure 3 may be used. During this test it is
necessary to measure the spill current in the relay circuit and short out the relay
and stabilising resistor (if fitted). The current is increased up to as near full load
as possible and the spill current noted. The spill current should be very low, only
a few milliamps if the connections are correct. A high reading (twice the injected
current, referred through the current transformer ratio) indicates that one of the
current transformers is reversed.
Injection should be carried out through each phase to netural.
Where primary injection is not practicable in the case of restricted earth fault
protection on a
transformer it may be possible to check stability by meansof back
energising the
transformer froma low voltage (415V) supply as shown in Figure 4.
In the case of machineprotection, similarstability tests
must be carried out by
injecting into one and out of anothercurrent transformer connected on the same
phase.
For large machines,the machineitself can be used to provide the fault current,
but the shortcircuit
must now be fitted as shown in Figure 6. The machineshould
be runup to
normal speed and the excitation increased untilthe primary currentis
approximately fullload, when the spill currentshouldbe checked.
All other types of balanced protection shouldbe tested in a similarmanner.
At the conclusionof the tests ensure that all connections are correctly restored
and any shortingconnections removed.
14

Stabilising resistor (if fitted)
Relay
A2
A1
Metrosil
Ammeter
(in plug bridge circuit)
V
Figure 1 Secondary injection of relay to check secondary operating current,setting voltage and
relay operating current.
A1
Primary injection
test set
V
Stabilising resistor (if fitted)
A2
Relay
Ammeter (in plug bridge circuit)
Figure 2 Sensitivity check of restricted earth fault schemeby primary injection.
15

A1
Primary injection
test set
A
B
C
Temporary connections
A2
Stabilising resistor (if fitted)
Relay
Metrosil
Figure 3 Stability check of restricted earth fault protection.
A1
A
LV
B
supply
C
Temporary short circuit
A2
Stabilising resistor (if fitted)
Relay
Figure 4 Stability check on restricted earth fault scheme by back energising with a low voltage supply.
16

Temporary short circuit
Generator
Isolating
links
A
B
C
V 87 87 87
87 Generator differential relay
V
V oltmeter
Figure 5 Testing sensitivity of generatordifferential protection using generatorto supply
primary current.
Generator
Isolating
links
Temporary short circuit
A
B
C
A2 A2 A2
87 87 87
87 Generator differential relay
A2
Ammeter
Figure 6 Checking stability of generatordifferential protection.
17

Section 3. MAINTENANCE
Periodic
maintenance is not necessary. However, periodic inspection and test is
recommended. This shouldbe carried out every l2 months or moreoften if the relay is
operated frequentlyor is
mounted in poor environmental conditions.
3.1 Repeat secondary injection tests 2.2.4 to prove operation, with emphasison
contact wear and condition. Mechanical settings may be checked against those
shown in Section
4.
Section 4. MECHANICAL SETTINGS
4.1 General
Armaturegap
measurements shouldbe made with the top of the feeler gauge
level with the centre line of the core.
Contact pressures are measuredwith a
gramme gauge at the contact tips.
In general contact gaps and follow
through are defined by quoting an armature gap
at which the tips shouldbe just closed or just open.
The relay contact state is always defined with the relay in the unenergised
position, unlessotherwise specified on the appropriate circuit diagram.
4.1.1 With the
armature closed the clearance between the back of the armature and
the back stop shouldbe
0.003"/0.008".
4.1.2 Nominal
armature gap open: 0.060" for all types.
Set screw in
armature so that armature gap when closed is approximately
0.005"/0.010".
4.2 Contact settings
4.2.1 Normal duty makecontacts
With the
armature closed onto a 0.011" feeler gauge the makecontacts shouldbe
closed, but shouldbe open using a 0.013" feeler gauge.
Contact settings
2 contacts
(MFAC
34)
4 contacts
(MFAC
14)
Force to just close the
make contacts 20/25 grams 15/20 grams
Force to just lift the fixed
contact off its support 15/20 grams
20/25 grams
Nominal contact gap
0.060"/0.080"
4.3 Mechanical flag settings
4.3.1 Settings for self reset units
MFAC
l4/34
With the armature closed on to a 0.013" feeler gauge the flag should be free to fall,
but shouldnot fall using an 0.018" feeler gauge. Adjustmentis made to the catch
spring on the flag.
18

Section 5. PROBLEM ANALYSIS
5.1 Failure to operate
Check diagram for correct input connections.
Check tap voltage; this is
marked above or below the plug bridge on the frontof the
module.
Note: with the plug removed the relay setting goes to the highest tap value.
Measure the input current at VS, this should be 38mA (excluding the
metrosil).
Flag spring may be
jammed between armature and core face, preventing armature
closure.
Check internalwiring for damage.
Check choke continuity
- resistance 240 ohms ± 15%.
Check resistor values
- removepcb frommoduleand fold down to gain access
to board.
Setting range Resistors on PCB ZJ0038
R1 – R3 R5–R6 R7–R8
R9
15–185 680Ω 680Ω 150Ω
120 Ω
Adjustable resistor
0 – 1000 Ω
Capacitor
3.3 µ F
Relay coil 190 Ω
Setting range Resistors on PCB ZJ0038
R1 –
R6
25–175
1.3K Ω
25–327
2.4K Ω
Adjustable resistor RV1
510 Ω
Capacitor C1
1.7 µ F ±5% 50Hz, 1.18 µ F ±5% 60Hz.
Relay coil 560Ω± 15%
Setting range Resistors on PCB ZJ0038
R1 – R6
100–400
2.7K Ω
R9
3.9K Ω
5.2 Output contacts not changing state
Check output
terminals with reference to appropriate diagram.
Operating pushrodsnot in position
Internal wiring damaged
Contamination of contacts
Contacts shouldbe cleaned with the burnishingtool supplied in the relay tool kits.
On no account shouldknives, files or abrasive materialsbe used.
Check mechanicalsettings as per Section
4.
19

Section 6. SPARES
When ordering spares, quote the full relay model number and any component
reference numbers, or briefly describe the parts required.
Should the need arise for the equipment to be returned to General Electric for
repair please fill in the RMA form at the back of this manual.
A copy of any commissioning test results should also be sent with the
equipment.
20