GE P24DM Technical Manual page 46

Chapter 2 - Safety Information
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.
Warning:
Data communication cables with accessible screens and/or screen conductors,
(including optical fibre cables with metallic elements), may create an electric shock
hazard in a sub-station environment if both ends of the cable screen are not connected
to the same equipotential bonded earthing system.
To reduce the risk of electric shock due to transferred potential hazards:
i. The installation shall include all necessary protection measures to ensure that no
fault currents can flow in the connected cable screen conductor.
ii. The connected cable shall have its screen conductor connected to the protective
conductor terminal (PCT) of the connected equipment at both ends. This connection
may be inherent in the connectors provided on the equipment but, if there is any doubt,
this must be confirmed by a continuity test.
iii. The protective conductor terminal (PCT) of each piece of connected equipment shall
be connected directly to the same equipotential bonded earthing system.
iv. If, for any reason, both ends of the cable screen are not connected to the same
equipotential bonded earth system, precautions must be taken to ensure that such
screen connections are made safe before work is done to, or in proximity to, any such
cables.
v. No equipment shall be connected to any download or maintenance circuits or
connectors of this product except temporarily and for maintenance purposes only.
vi. Equipment temporarily connected to this product for maintenance purposes shall be
protectively earthed (if the temporary equipment is required to be protectively
earthed), directly to the same equipotential bonded earthing system as the product.
Warning:
Small Form-factor Pluggable (SFP) modules which provide copper Ethernet connections
typically do not provide any additional safety isolation. Copper Ethernet SFP modules
must only be used in connector positions intended for this type of connection.
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P24xM
P24xM-TM-EN-2.1