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1MRS 752264-MUM
Motor Protection Relay
Operator’s Manual
REM 610
4.
Commissioning and maintenance
The relay should be subject to regular tests and maintenance in accordance with
national regulations and instructions.
Prior to commissioning, the functionality of the application-specific relay
configuration and settings have to be tested.
During relay commissioning, the operation of short-circuit and earth-fault protection
is to be tested using secondary injection testing in order to secure personal safety.
Additionally, correct operation of input and output signals to and from the relay
should be verified.
REM 610 is a numerical protection relay with functionality implemented in the relay
software configuration. Software functionality does not change over time and the
relay performs extensive self-supervision during operation. Therefore, it is not
necessary to perform extensive relay testing during periodic maintenance.
When the protection relay is operating under the specified conditions (refer to the
Technical Reference Manual), the manufacturer recommends preventive
maintenance to be performed every five years. This periodically performed
preventive maintenance is to be carried out to secure correct and safe operation of
the relay. When performing preventive maintenance, the correct functionality of the
relay is to be verified as well as the wiring circuitry to and from the relay.
If the environmental conditions at the relay operating site differ from those
specified, for instance temperature and humidity, or if the atmosphere around the
relay contains chemically active gases or dust, the relay ought to be visually
inspected. At the visual inspection, the following should be observed:
• Signs of mechanical damage on the relay, contacts and relay case.
• Rust spots or signs of corrosion on the terminals or case.
4.1.
Commissioning instructions
Relay commissioning is carried out to confirm correct operation of the relay when
it is taken into use. Polarity checking of phase current transformers (CTs) should be
performed to confirm that the wiring circuitry between the CTs and the relay is
correct, which is a prerequisite for the protection functions in the relay to operate
correctly. The circuit breaker tripping circuit, interlocking and signalling wiring
should also be tested.
When commissioning the relay, secondary injection testing is performed to secure
personal safety in case of short circuits or earth faults in the system. If desired,
secondary injection testing can also be used for more elaborate testing of the relay’s
functionality.
Danger!
Do not open the secondary circuit of a current transformer during
any phase of the testing when the primary circuit is live. The high
voltage generated by an open CT secondary circuit may be lethal
and damage instruments and insulation.
!
