Measurements Verification; Relay Verification; Preventive Parts Replacement - ABB REM 610 Operator's Manual

1MRS755538
5.2.1.
5.2.2.
5.3.
Motor Protection Relay
Operator's Manual - ANSI version

Relay verification

The relay maintenance verification contains:
1. Verifying measurements – can be performed according to the instructions in
Section 5.3. Measurements verification.
2. Verifying output contacts operation – can be performed according to the
instructions in Section 5.4. Function test.
The circuit breaker tripping circuit should be disconnected from the
relay during this verification, in order to avoid unwanted operation in
the system. Interlocking signals should also be disconnected from the
relay during the verification in order to avoid dangerous situations
from occurring in the system.
3. Verifying digital inputs operation – can be performed according to the
instructions in Section 5.5. Digital input test.

Preventive parts replacement

When being used for real-time clock and recorded data functions, the battery should
be changed every five years. Refer to Section 4.4.3. Inserting and changing the
battery.

Measurements verification

As most of the protection functions in the protection relay are based on the phase
currents and ground-fault current measured by the relay, it is important to verify that
the relay is measuring proper values.
This measurements verification can be performed by examining the current readings
on the display while injecting a pure sinusoidal current into the current input. If the
reading on the display corresponds to the calculated value, taking the relay accuracy
and display resolution into account, the relay is measuring proper values.
Rated current for the energizing input that is being verified is shown on the relay
label under the lower handle of the relay.
The protected unit scaling factor, used for motor full load current FLA
compensation, has to be taken into account when verifying phase currents measured
by the relay.
The value to be shown on the display is calculated as follows:

FLA
) =
Value on LCD (


energizing input rated

Injected current
×
FLA secondary factor


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REM 610 REM 610
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