Verifying safe isolation from supply
139-2021.9 / 07
NXAIR M
127
16.4 Verifying LRM-ST voltage indicator
To verify proper functioning of the LRM-ST voltage indicator, use the battery-operated function test unit
(optional).
Fig. 213: Function test unit for LRM-ST voltage indicator
Preconditions
Function test unit available ready for operation on LRM-ST voltage indicators
LRM voltage indicator available to be tested
Procedure
Plug the contact pins of the LRM-ST voltage indicator into the test sockets at the function
test unit.
Perform the test.
Alternative test method
If no function test unit is available to check the LRM-ST voltage indicator, the check must be executed on a
live panel:
Procedure
Remove the cover from the test sockets; the cover remains permanently at the panel.
Plug the contact pins of the LRM-ST voltage indicator into the test sockets at the panel.
Perform the test.
The test of the LRM-ST voltage indicator is completed. If the voltage indicator does not pass
the function test, do not use this voltage indicator to verify safe isolation from supply.