Multi-source ground fault – GE Industrial Solutions EntelliGuard R AKD-6 User Manual
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EntelliGuard R Circuit Breaker Retrofill AKD-6 Installation Manual DEH-41548 02/12
3. The existing neutral CT assemblies are usually mounted vertically on two copper bus bars placed horizontally.
4. Disconnect the wires that are attached to the existing CT assemblies and place them so that they do not
interfere with the replacement of the CT assemblies.
5. Unfasten and remove the bolts holding the neutral disconnect assemblies to the horizontal bus bars. Keep the
hardware in a secure location for reassembly.
6. Care should be taken while handling the CT assemblies so that they do not fall down or damage other
components within the LVS.
7. Replace the old CT assembly by the new Rogowski assembly on the horizontal bus bars and fasten it using the
hardware previously removed.
8. Connect the wires back to the Rogowski CT assembly leads. In case of damaged wires, the same must be
replaced with new ones as already mentioned.
9. Check for continuity from the CT leads to the plungers on the neutral-disconnect assemblies within the LVS
compartment.
10. The new Rogowski assemblies are installed and ready for use.
Tools required: Wrenches, Wire stripper, wire cutter, continuity tester.
Multi-Source Ground Fault
Retrofils can be used in the following ground fault applications:
• Single Source Feeder breakers, 3 wire or 4 wire
• Main Circuit breakers, 3 wire or 4 wire
When multi-sources are present with the ground fault detection on the trip unit desired, then an external GF
summing CT scheme must be implemented. This applies to main—tie—main systems or systems with a main
source and then a back-fed generator source.