Maintenance, troubleshooting, messages
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VMD460-NA_D00001_05_M_XXEN/01.2020
7. Maintenance, troubleshooting, messages
7.1 Recurrent test of the tripping circuit by the system operator
The system operator must ensure that the equipment required for parallel operation
with the low-voltage network is always in proper technical condition. To this end, it is
required to have an electrically skilled person check the protective devices for proper
functioning at regular intervals. This requirement is deemed to be satisfied for normal
and environmental conditions if the test intervals mentioned in BGV A3 are adhered to.
The recurrent tests must include at least the following:
•
Testing the environmental conditions for pollution, mechanical damage or insulation
damage.
•
Tripping control of the interface switch.
•
Press the "TEST" button to trigger the interface switch.
•
Successful activation must be visualised by the interface switch.
The tripping circuit NS protection/interface switch, in the wiring diagram of this operat-
ing manual consisting of K1/K2 and interface switch 1/interface switch 2, disconnects
the generating plant from the public low-voltage network. By checking the tripping cir-
cuit regularly, sticking of the contactor contacts can be detected at an early stage.
7.2 Manual self test
The self test can only be started manually when the generating plant has been connect-
ed by the VMD460-NA (both alarm LEDs off) and an undervoltage limit value has been
set.
Start of the manual self test:
1. Press the test button on the standard display (> 1.5 s) or
2. Select
4. System --> 7. Test
in the menu.
The output relays K1 and K2 switch during the self test and open or close the contacts
11/12/14 and 21/22/24.
Both interface switches are disconnected during the self test.
