Disassemble and reassemble the IED accordingly:
1. Switch off the dc supply.
2. Short-circuit the current transformers and disconnect all current and voltage connections from the
IED.
3. Disconnect all signal wires by removing the female connectors.
4. Disconnect the optical fibers.
5. Unscrew the main back plate of the IED.
6. If the transformer module is to be changed:
• Remove the IED from the panel if necessary.
• Remove the rear plate of the IED.
• Remove the front plate.
• Remove the screws of the transformer input module, both front and rear.
7. Pull out the faulty module.
8. Check that the new module has a correct identity number.
9. Check that the springs on the card rail are connected to the corresponding metallic area on the
circuit board when the new module is inserted.
10. Reassemble the IED.
If the IED has been calibrated with the system inputs, the calibration procedure must be performed again
to maintain the total system accuracy.
15.4 Repair support
M11768-3 v4
If an IED needs to be repaired, the whole IED must be removed and sent to an Hitachi Power grids
Logistic Center. Please contact the local Hitachi Power grids representative to get more details.
15.5 Maintenance
M11769-3 v2
The IED is self-supervised. No special maintenance is required.
Instructions from the power network company and other maintenance directives valid for maintenance of
the power system must be followed.
1MRK 504 165-UUS Rev. J Section 15
Troubleshooting
Transformer protection RET670 313
Commissioning manual
© 2017 - 2021 Hitachi Power Grids. All rights reserved
To Next Page
Loading...
