Areva MiCOM P441, Technical Manual

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Commissioning P44x/EN CM/E33
MiCOM P441/P442 & P444 Page 49/54
Refit the front panel using the reverse procedure to that given in section 8.3.2. After refitting
and closing the access covers on case sizes 60TE, press at the location of the hinge-
assistance T-pieces so that they click back into the front panel moulding.
Once the relay has been reassembled after repair, it should be recommissioned in
accordance with the instructions in sections 1 to 7 inclusive of this chapter.
8.3.2.3 Replacement of the input module
The input module comprises of two boards fastened together, the transformer board and the
input board.
The module is secured in the case by two screws on its right-hand side, accessible from the
front of the relay, as shown in figure 27. Remove these screws carefully as they are not
captive in the front plate of the module.
Input module
Handle
P3010ENa
FIGURE 27 - LOCATION OF SECURING SCREWS FOR INPUT MODULE
On the right-hand side of the analogue input module there is a small metal tab which brings
out a handle. Grasping this handle firmly, pull the module forward, away from the rear
terminal blocks. A reasonable amount of force will be required to achieve this due to the
friction between the contacts of two terminal blocks, one medium duty and one heavy duty.
NOTE: Care should be taken when withdrawing the input module as it will
suddenly come loose once the friction of the terminal blocks has been
overcome. This is particularly important with loose relays as the metal
case will need to be held firmly whilst the module is withdrawn.
Remove the module from the case, taking care as it is heavy because it contains all the
relay’s input voltage and current transformers.
The replacement module can be slotted in using the reverse procedure, ensuring that it is
pushed fully back on to the rear terminal blocks and the securing screws are re-fitted.
NOTE: The transformer and input boards within the module are calibrated
together with the calibration data being stored on the input board.
Therefore it is recommended that the complete module is replaced to
avoid on-site recalibration having to be performed.
Refit the front panel using the reverse procedure to that given in section 8.3.2. After refitting
and closing the access covers on case sizes 60TE, press at the location of the hinge-
assistance T-pieces so that they click back into the front panel moulding.
Once the relay has been reassembled after repair, it should be recommissioned in
accordance with the instructions in sections 1 to 7 inclusive of this chapter.