Areva MiCOM P125, Technical Manual

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Pxxxx/EN SS/B11
Page 6/10 Safety Section
External resistors, including voltage dependent resistors (VDRs)
Where external resistors, including voltage dependent resistors (VDRs), are
fitted to the equipment, these may present a risk of electric shock or burns, if
touched.
Battery replacement
Where internal batteries are fitted they should be replaced with the
recommended type and be installed with the correct polarity to avoid possible
damage to the equipment, buildings and persons.
Insulation and dielectric strength testing
Insulation testing may leave capacitors charged up to a hazardous voltage. At
the end of each part of the test, the voltage should be gradually reduced to zero,
to discharge capacitors, before the test leads are disconnected.
Insertion of modules and pcb cards
Modules and pcb cards must not be inserted into or withdrawn from the
equipment whilst it is energised, since this may result in damage.
Insertion and withdrawal of extender cards
Extender cards are available for some equipment. If an extender card is used,
this should not be inserted or withdrawn from the equipment whilst it is
energised. This is to avoid possible shock or damage hazards. Hazardous live
voltages may be accessible on the extender card.
Insertion and withdrawal of integral heavy current test plugs
It is possible to use an integral heavy current test plug with some equipment.
CT shorting links must be in place before insertion or removal of heavy current
test plugs, to avoid potentially lethal voltages.
External test blocks and test plugs
Great care should be taken when using external test blocks and test plugs such
as the MMLG, MMLB and MiCOM P990 types, hazardous voltages may be
accessible when using these. *CT shorting links must be in place before the
insertion or removal of MMLB test plugs, to avoid potentially lethal voltages.
*Note – when a MiCOM P992 Test Plug is inserted into the MiCOM P991 Test
Block, the secondaries of the line CTs are automatically shorted, making them
safe.
Fibre optic communication
Where fibre optic communication devices are fitted, these should not be viewed
directly. Optical power meters should be used to determine the operation or
signal level of the device.
Cleaning
The equipment may be cleaned using a lint free cloth dampened with clean
water, when no connections are energised. Contact fingers of test plugs are
normally protected by petroleum jelly which should not be removed.