Areva MiCOM P341, Operation Manual

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Operation Guide P341/EN O/B11
Problem Analysis CHAPTER 4
MiCOM P341 Page 7/8
Test Check Action
8 The VT type field in the model
number is incorrect (no VTs
fitted)
Table 4: Out of service LED illuminated
6. ERROR CODE DURING OPERATION
The relay performs continuous self-checking, if an error is detected then an error
message will be displayed, a maintenance record will be logged and the relay will
reset (after a 1.6 second delay). A permanent problem (for example due to a
hardware fault) will generally be detected on the power up sequence, following which
the relay will display an error code and halt. If the problem was transient in nature
then the relay should re-boot correctly and continue in operation. The nature of the
detected fault can be determined by examination of the maintenance record logged.
There are also three cases where a maintenance record will be logged due to a
detected error where the relay will not reset. These are detection of a failure of either
the field voltage, the lithium battery, or the RTD board. In these cases the failure is
indicated by an alarm message, however the relay will continue to operate.
If the field voltage is detected to have failed (the voltage level has dropped below
threshold), then a scheme logic signal is also set. This allows the scheme logic to be
adapted in the case of this failure (for example if a blocking scheme is being used).
In the case of a battery failure it is possible to prevent the relay from issuing an alarm
using the setting under the Date and Time section of the menu. This setting "Battery
Alarm" can be set to 'Disabled' to allow the relay to be used without a battery, without
an alarm message being displayed.
In the case of the RTD board failure, an alarm "RTD board fail" message is displayed,
the RTD protection is disabled, but the operation of the rest of the relay functionality is
unaffected.
7. MIS-OPERATION OF THE RELAY DURING TESTING
7.1 Failure of output contacts
An apparent failure of the relay output contacts may be caused by the relay
configuration, the following tests should be performed to identify the real cause of the
failure. Note that the relay self-tests verify that the coil of the contact has been
energised, an error will be displayed if there is a fault in the output relay board.
Test Check Action
1 Is the Out of Service LED
illuminated
Illumination of this LED may
indicate that the relay is in test
mode or that the protection has
been disabled due to a hardware
verify error(see Table4)
2 Examine the Contact status in the
Commissioning section of the
menu.
If the relevant bits of the contact
status are operated then proceed to
test 4, if not proceed to test 3.