Areva MiCom P120, Техническое руководство

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Pxxxx/EN SS/E11
Safety Section 5/8
Current transformer circuits
Do not open the secondary circuit of a live CT since the high voltage produced
may be lethal to personnel and could damage insulation. Generally, for safety,
the secondary of the line CT must be shorted before opening any connections to
it.
For most equipment with ring-terminal connections, the threaded terminal block
for current transformer termination has automatic CT shorting on removal of the
module. Therefore external shorting of the CTs may not be required, the
equipment documentation should be checked to see if this applies.
For equipment with pin-terminal connections, the threaded terminal block for
current transformer termination does NOT have automatic CT shorting on removal
of the module.
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Modules and PCB cards must not be inserted into or withdrawn from the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 energized, 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this should not be inserted or withdrawn from the equipment whilst it is energized.
This is to avoid possible shock or damage hazards. Hazardous live voltages may
be accessible on the extender card.
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.
Fiber optic communication
Where fiber 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 energized. Contact fingers of test plugs are normally
protected by petroleum jelly, which should not be removed.