Areva MiCOM P225, Technical Manual

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Installation Guide P225/EN IN/B11
MiCOM P225 Page 9/12
7. INSTALLATION, COMMISSIONING AND MAINTENANCE
7.1 Connection of the MiCOM P225 relay
The personnel in charge of the installation, commissioning and maintenance of a MiCOM
P225 relay must apply adequate procedures to guarantee safety when using the equipment.
Before installation, commissioning or maintenance on the equipment, consult the relevant
chapters in the technical documentation of the relay.
The terminal blocks of the relays may have a dangerously high voltage during installation,
commissioning or maintenance, if electrical isolation is not carried out.
Access to the connectors at the rear of the relays can present risks of electrocution and
thermal shock.
Before you consider energization, the MiCOM P225 relay must be connected to earth via the
terminal provided for this purpose.
Unless otherwise indicated in the technical data chapter of the product documentation, the
minimum size recommended for the earth wire is 2.5 mm
2
.
Before energising your MiCOM P225 relay, please check the following points:
−
Rated voltage and polarity of the auxiliary power supply
−
Current value of the current transformer circuit and integrity of the connections
−
Integrity of the earth connection.
7.2 Operating conditions of the MiCOM P225 relay
The operation of the MiCOM P225 relay must comply with the electrical and environmental
requirements described in this document.
7.3 Replacement of the batteries
The internal batteries, if used, must be replaced by batteries corresponding to the type
recommended. They must be installed with the correct polarity, to avoid any risk of damage
to the equipment.
7.4 Current transformer circuits
Never open the auxiliary circuit of a live current transformer. The high voltage produced may
cause serious physical injury and damage the insulation of the equipment.
7.5 Dielectric withstand test
Following an insulation test, the capacitors may still be charged with a potentially dangerous
voltage. At the end of each part of the test, the voltage must be progressively brought down
to zero to discharge the capacitors before disconnecting the test wiring.
7.6 Removal and destruction of the MiCOM P225 relay
7.6.1 Removal
The auxiliary power supply circuit of the relay can include capacitors for the power supply or
for earthing. To avoid any risk of electrocution or thermal shock, it is appropriate to isolate
the relay completely (the two direct current poles) from any power supply, then to discharge
the capacitors in complete safety via the external terminals, before taking the device out of
service.