You said you are troubleshooting but maybe you could tell what the symptoms are. That would be helpful. I'd have to guess that failure to start without a battery in place is normal. No load or excessive load causes some types of power supplies to shut down. There might be a way to rig a dummy load to the charging circuit that would work but I can't tell you how to make such. Look at the battery and see what voltage it provides. If 12v, you could try an automotive head or tail light as these would check through a wide range of current.
Hi
I am troubleshooting my UPS. Can you switch-on the UPS without the batteries (just to check)? I think the UPS will only switch to batteries only if cannot detect power from the mains, but my UPS doesn't switch on so I'm not sure if I am right. Can someone verify this?
thanks,
Franko

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