Alstom MiCOM P846, Technical Manual

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Troubleshooting P846/EN TS/D
MiCOM P846
(TS) 12-3
TS
1. INTRODUCTION
Before carrying out any work on the equipment, the user should be familiar with the contents
elay
st cases to identify which
returned to the manufacturer or one of their
2.
of the safety and technical data sections and the ratings on the equipment’s rating label
The purpose of this section of the service manual is to allow an error condition on the r
to be identified so that appropriate corrective action can be taken.
Should the relay have developed a fault, it should be possible in mo
relay module requires attention. The Maintenance section (P846/EN MT), advises on the
recommended method of repair where faulty modules need replacing. It is not possible to
perform an on-site repair to a faulted module.
In cases where a faulty relay/module is being
approved service centers, completed copy of the Repair/Modification Return Authorization
Form located at the end of this section should be included.
INITIAL PROBLEM IDENTIFICATION
Consult the table below to find the description that best matches the problem experienced,
then consult the section referenced to perform a more detailed analysis of the problem.
Symptom Refer To
Relay fails to power up Section 4
Relay powers up - but indicates error and halts during
power-up sequence
Section 5
Relay Powers up but Out of Service LED is illuminated Section 6
Error during normal operation Section 7
Mal-operation of the relay during testing Section 8
T
3.
able 1: Problem identification
POWER UP ERRORS
If the relay does not appear to power up then the following procedure can be used to
Action
determine whether the fault is in the external wiring, auxiliary fuse, power supply module of
the relay or the relay front panel.
Test Check
1
Measure au voltage on
c, 2 is +dc
If auxiliary voltag ent and correct, xiliary
terminals 1 and 2; verify voltage
level and polarity against rating the
label on front.
Terminal 1 is –d
e is pres
then proceed to test 2. Otherwise the
wiring/fuses in auxiliary supply should be
checked.
2
t If they illuminate or the contact closes and no Do LEDs/and LCD backligh
illuminate on power-up, also check
the N/O watchdog contact for
closing.
error code is displayed then error is probably
in the main processor board (front panel). If
they do not illuminate and the contact does
not close then proceed to test 3.
3
Check Field voltage output the fault is
(nominally 48V DC)
If field voltage is not present then
probably in the relay power supply module.
Table 2: power up Failure of relay to