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RELAYS AND LEDS
Relays and LEDs selftests are executed as follows:
First all of the relays and LEDs are switched off, then they are
switched on one at a time for a few seconds and cyclically.
User can interrupt the otherwise endless cycle, as indicated
by the scrolling message, by pressing a key.
Note
Relays and LEDs test has to be carried out with the relay
contacts disconnected from external plant devices.
WATCHDOG
When a dead loop condition is detected a reset is automat-
ically invoked.
The effectiveness of watchdog capability can be tested
through one of the special setup items. This test consists of
executing a dummy dead loop that causes watchdog reset
signal to be generated.
