User Manual

Publication 1000-UM001B-US-P - July 2000
5-4 Troubleshooting Guide
10. One at a time, check operation of SLS switches by turning to OFF
position, and check for the following:
a. SAFE light on.
b. IC drop ped out .
c. 1 C R drop ped out.
d. Safety relay SR dropped out
e. VSR indicates safe condition.
11. VSR volta ge sensin g bro ken wire detect ion test.
a. W ith power off, remo ve one voltag e-s ens in g wi re from the V S R.
Then, with all SLS switches in the ON position, apply power and
turn a SLS switch off. The result s hould be that the saf e light does
not illuminate (after cycling an SLS switch) and the system fault LED
is on. The VSR voltage hazard LED will now turn on. Turn power
off, reconnect voltage sensing wire and repeat check with the VSR
redundant voltage sensing circuit.
b. Each separately, do the same test with the two N* circuits. (No initial
fault on VSR, only when the SLS switch is turned to off does the
system fault ligh t come on.)
12. Safety relay cable shor ting checks
a. Wit h all pow er off, in stall a short ing jum per on Alle n- Bra dley saf ety
relay 700-ZBL be tween termina l s S1 0 and S11. Th en po wer up the
system with all SLS sw itches in the ON position . Turn a SLS sw itch
to the O FF position. The SAFE light should n ot come on. Observe
that CH2 and K1 LEDs are off on the safety rela y. Turn off all power
and remove shorting jumper.
b. W ith all pow er off, in stal l a shorting jum per on All en- Bra d ley safety
relay 700-ZBL between terminals S21 and B2. Then power up the
system with all SLS sw itches in the ON position . Turn a SLS sw itch
to the O FF position. The SAFE light should n ot come on. Observe
that CH1 and K2 LEDs are off on sa fety relay. Turn off al l power
and remove shorting jumper.