Siemens SM322 32xDO 24VDC/0.5A Power Supply

[TodHead]

This is a rephrasing of an earlier thread - which should be deleted - sorry, I'm new new to the forum concept - don't know how to delete an earlier thread!

Please advise if it is acceptable to use the CPU power supply unit PS 307 5A 24VDC/0VDC supply outlets to power a SM322 32xDO 24VDC/0.5A (6ES7 322-BL00-0AA0) module.

I have wired the DO module front connector correctly and connected it to the PS 307 5A in order to observe the LED indication of output status.

There were no lamps or other loads connected to the outputs.

Now, with the module re-established in its industrial setting and connected up to indicator lamps I find there is insufficient power to drive more than 2 lamps whereas last week, before taking the module out, ALL lamps could be simultaneously driven - during Lamp Test for example

Could the module have been damaged by operating it without output load in the form of the indicator lamps?

When I connect certain lamps other LEDs on module glow or pulse dimly even though output is "0" - a possible earth fault?

 

[iant]

Ok
1st - simply post on the last thread that it has been replaced and copy a link to this one - I'll do that for you shortly -
2nd.
if this is a new card on an existing system then remember the power supply is for the whole system not just that card.
it is common to see more than one supply
a 5A and a 10 or 20 Amp in a panel.
Please give a few more details.

 

[KalleOlsen]

I have wired the DO module front connector correctly

It might be smart to clean the spectacles, find a torch and quadrippel-check this

Kalle

 

[TodHead]

Thanks IanT and KalleOlsen for your help.

The cause of the symptoms turns out to be a 0V contact knife being open; hence, presumably, no reference voltage and the strange output characteristics.

On replacing knife contact all is as expected.

So, in reply to my own question, it would appear that using the PS 307 PSU for powering DO module without load for bench test purposes is an acceptable procedure and the module is undamaged - phew!