Alstom MiCOM P846, Technical Manual

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Safety Section P846/EN SS/H11
(SS) - 7
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.
SS
5. DE-COMMISSIONING AND DISPOSAL
De-commissioning
The supply input (auxiliary) for the equipment may include capacitors across the
supply or to earth. To avoid electric shock or energy hazards, after completely
isolating the supplies to the equipment (both poles of any dc supply), the
capacitors should be safely discharged via the external terminals prior to
de-commissioning.
Disposal
It is recommended that incineration and disposal to water courses is avoided.
The equipment should be disposed of in a safe manner. Any equipment
containing batteries should have them removed before disposal, taking
precautions to avoid short circuits. Particular regulations within the country of
operation, may apply to the disposal of the equipment.