Problem 2 – Rockwell Automation 1771-P4R_P6R Allen-Bradley Redundent Power Installation Instructions User Manual
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Allen-Bradley Redundant Power Supplies
17
Publication 1771-IN030B-EN-P - July 2002
Problem 2
All the supplies in the redundant system have their P/S ACTIVE
indicators off. The NON REDUNDANT SYSTEM LED may or
may not be on.
Turn off the power supply and wait 5 seconds. Then turn on the power
supplies simultaneously.
P/S Active
ON?
yes
no
Done
Turn off the power supplies and wait 5 seconds. Test each power supply
individually. Pull the first power supply half way out of the chassis. Open
switches 5 and 6 and remove the redundant cables. Turn on the power supply
to test it without a load. Repeat for the other power supplies.
P/S Active
Off?
yes
no
If ac voltage is OK, replace the
power supply, but do not turn
the ac power switch on.
Continue to test other supplies.
Turn off the power supply and wait 5 seconds. Reset switches 5 and 6 to original
positions and reinsert the redundant cables. Firmly seat the power supply into the
backplane, then turn on the power supply again.
P/S Active
ON?
no
Done
Using a known good supply, swap out each power supply with the known good
power supply. Be sure to correctly set the I.D. switches.
P/S Active
ON?
yes
Done
P/S Active
ON?
yes
no
Done
Turn off the power supply and check the redundant cables for continuity and
shorts. These shielded 6Ćconductor cables are 1:1.
P/S Active
ON?
yes
no
Done
Try replacing the I/O modules (one of them could be overloading the supplies).