GE P50 Agile P253, Technical Manual

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Pxxx Safety
Information
9
Caution:
Check integrity of the PCT connection.
Caution:
Check voltage and current rating of external wiring, ensuring it is appropriate for
the application.
3.8 PERIPHERAL CIRCUITRY
Warning:
Do not open the secondary circuit of a live CT since the high voltage produced
may be lethal to personnel and could damage insulation. Short the secondary of
the line CT before opening any connections to it.
Note:
For most General Electric equipment with ring-terminal connections, the threaded terminal block for current
transformer termination is automatically shorted if the module is removed. Therefore external shorting of the CTs
may not be required. Check the equipment documentation and wiring diagrams first to see if this applies.
Caution:
Where external components such as resistors or voltage dependent resistors
(VDRs) are used, these may present a risk of electric shock or burns if touched.
Warning:
Take extreme care when using external test blocks and test plugs such as the
MMLG, MMLB and P990, as hazardous voltages may be exposed. Ensure that CT
shorting links are in place before removing test plugs, to avoid potentially lethal
voltages.
3.9 UPGRADING/SERVICING
Warning:
Do not insert or withdraw modules, PCBs or expansion boards from the
equipment while energised, as this may result in damage to the equipment.
Hazardous live voltages would also be exposed, endangering personnel.
Caution:
Internal modules and assemblies can be heavy and may have sharp edges. Take
care when inserting or removing modules into or out of the IED.