GE MVAX 11, Техническое руководство

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Equipment operating conditions
The equipment should be operated within the specified electrical
and environmental limits.
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Modules and PCB cards must not be inserted into or withdrawn from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.
I
nsertion 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card is used, this should not be inserted or withdrawn from the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