Product Functions; Self-Diagnosis Function - Gewiss GW 90 901 Bedienungsanleitung

PRODUCT FUNCTIONS

RESTART / AUTOTEST is a device incorporating the possibility of
making a weekly self-diagnosis, both electrical and mechanical, without
interrupting the power supply of the system connected to it.
A possible fault condition is signalled if anomalies are detected when in
test mode.
The device is provided with additional differential protection able to
detect the failure of the differential switch to uncouple following a
leakage in the system and to make it do so by generating a reinforced
impulse directed at the relay.
The self-diagnosis function consists in making the differential switch
carry out an uncoupling manoeuvre every week by simulating manual
pressing of the test key.
The test consists of the following phases with an overall duration of
approximately 2 minutes:
- Closing a bypass circuit in parallel with the power contacts of the
differential switch
- Injecting an earth escape current equal to the rated Idn current to
cause the differential switch to open
- An electronic test of the condition of all the electrical and mechanical
parts of the device
- Reclosing the power contacts of the differential switch by resetting
the lever
- Reopening the bypass circuit and returning to the initial condition of
normal operation.
The time the periodic test is made can be defined using the
synchronisation function. Differential protection is present during all the
test phases in any case.

SELF-DIAGNOSIS FUNCTION

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