ABB Emax 2 Retrofill, Installation And Maintenance Manual

Page: 62 / 77

Figure 60
For Detail Instructions on NCT Adaptor refer installation manual No 2TSA451018P0000
Wiring Diagram
Ensure that the LVS has been de-energized and the breaker in the compartment being
retrofit is switched off and removed from the LVS.
Open the door on the rear of compartment to access the Cable/ Bus compartment of
the LVS
Note that the existing neutral CT assemblies are usually mounted vertically on two
copper bus bars placed horizontally.
Disconnect the wires that are attached to the existing CT assemblies and place them
such that they do not interfere with the replacement of the CT assemblies.
Unfasten and remove the bolts that hold the neutral disconnect assemblies to the
horizontal bus bars. Keep the hardware in a secure location for reassembly.
Be careful while handling the CT assemblies such that they do not fall down or damage
other components within the LVS.
Replace the old CT assembly with the new Rogowski assembly on the horizontal bus bars
and fasten it using the hardware previously removed.
Connect a twisted pair of wires back to the Rogowski CT assembly leads.
Check for continuity from the CT leads to the A24 and A25 secondary disconnect screw
terminal within the LVS compartment. NEVER push probes into the front of the
secondary disconnect.
The new Rogowski assemblies are installed and ready for use.
Tools required: Wrenches, wire stripper, wire cutter, continuity tester.
32 - Procedures
Write down the orientation of the existing
Iron core CT and the polarity of the
connections. The orientation and polarity
NOTICE needs to be matched when the air
core Rogowski is assembled in the cable
compartment.
NEUTRAL CT ORIENTATION
Notice
C