UPS Won't Supply 240v When Mains is Cut

[GT250]

Hi all,
Hope all are well on Austech

Have my own CyberPower UPS that (after a while, I realised after faffing around with my solar stuff), it is not allowing the batteries in the UPS to power the 240v items I had 'thought was protected'.

So undid all the cables and popped it onto a bench for a closer look.

The UPS is about 4 months out of warranty and CyberPower are not interested in even giving a quote to repair it (Malaysian call center), not even getting back to me with a price or where to send it to...

So opened her all up and plugged in a test table lamp to the back of the mains powered UPS (which has 4 GPO's), so when I unplugged the mains, the lamp went off...
Plugged back in the mains the lamp comes on, and so on...

The UPS display shows the batts at full and all other conditions/voltages nominal.
I measured the batts and they read 25.xx VDC.
When I disconnect the mains I hear a clicking (which I guess is normal, something has to 'switch'). The UPS I have is supposed to have the 'no delay' from 'disconnect to supply the load'.

I'm thinking it's the relays on the left of the board picture. Here's why... The two connections [BLU] [BRN] at the yellow (cap?), are the cables that supply the GPO's.
I was going to replace them, but my local Jaycar didn't have specs relay. So I thought I'd pop my issue here on Austech and see what the experts think, before I go down the path that I'm correct about these two relays, before the hassle of getting these relays.

The THICK Red and Black are from the 12v x 4 batts. The Red and Blue are the 240v.
PS: 40A fuses are ok
BTW: Where do you think I should get these relays. Local, or just feebay?

Here's some pics...

[loopyloo]

Be careful in there mate. Them things are dangerous.
Disconnect the batteries and wait for discharge before playing around in there.

[Reschs]

First question. Is the inverter running ?
When the mains fail the batteries feed a DC to 240V ac Inverter.
So are the battery voltages still in range with no AC Power ?
Do you have 240V on the output of the Inverter ?

[GT250]

Yeah, loopyloo, I know. Being careful

Resch. The (Inverter?), you mean the UPS? If it's running fine...

It turns on fine. All the displays (cycle button), show what it should show. Batt capacity 100% etc etc.

I assume the inverter is working as anything plugged into the GPO's run fine - as long as the grid mains is plugged in.

The batts are reading full voltage (4x12v), 2`5.xx vdc when no mains is applied.

Yes 240v power is on the GPO's when on mains power. When there is no mains (grid), 240v, then nothing comes out the GPO's.
The two connections at the two relays blu & brn are the cables that split to the 4 GPO's.

In the past when there has been a power cut (rare), or I've been faffing with my solar stuff. There's always been a warning beep and clicking before the batts cut in and the then (from memory), one can see the run time in the display counting down.
But now it beeps and clicks and won't even power a table lamp.

It's as though it's working fine, but no power out the GPO's when the grid mains is disconnected.

[shred]

Are you sure the batteries are ok? Apart from battery problems, I've always found UPSes to be very reliable.

Try measuring the battery terminal voltage across each battery with a 12v light globe across it to load the battery up a bit. I've never had anything to do with "Cyber Power", but I know the older APC SmartUPS UPSes were notorious for over-charging their batteries, with the predictable result that the batteries died very quickly (typically 18 months). Once this happened, the UPS wouldn't hold the load up at all - even though in many cases, the open circuit battery voltage suggested the battery was ok.

The fact that it powers the load when the mains is connected doesn't mean the inverter is working. The type of UPS you have there will switch mains through to the output while there is good mains power available. When the mains fails, it powers up the inverter and connects it to the output.

The "good" UPSes used to power larger installations of computer servers ("online" UPSes) run the inverter constantly to ensure perfectly clean power even while switching from mains power to battery. The inverters in these are designed for 100% duty cycle and are much bigger and beefier than the one you have there.

If you're in Northern Tas, I've got an older UPS kicking around that you could have, but due to size and weight, there's no way I'm posting it!

[GT250]

Shred: Spent many a few weeks in Tassie this year, around the time we were at that car rally show was on in Hobart and also there at the search and rescue that was going on in Strathgordon. If I would have known my UPS was to fail - it probably had already (in Warranty!), I'd have flown back with your UPS

I was wondering people, If I can test the relays in circuit?

Either mains on or mains off. Just to see if it is the relays acting up

[mtv]

I was wondering people, If I can test the relays in circuit?

You should be able to test if the relay contacts are open or closed, according to the coil being energised.

[Reschs]

Yeah, loopyloo, I know. Being careful

Resch. The (Inverter?), you mean the UPS? If it's running fine...

It turns on fine. All the displays (cycle button), show what it should show. Batt capacity 100% etc etc.

I assume the inverter is working as anything plugged into the GPO's run fine - as long as the grid mains is plugged in.

The batts are reading full voltage (4x12v), 2`5.xx vdc when no mains is applied.

Yes 240v power is on the GPO's when on mains power. When there is no mains (grid), 240v, then nothing comes out the GPO's.
The two connections at the two relays blu & brn are the cables that split to the 4 GPO's.

In the past when there has been a power cut (rare), or I've been faffing with my solar stuff. There's always been a warning beep and clicking before the batts cut in and the then (from memory), one can see the run time in the display counting down.
But now it beeps and clicks and won't even power a table lamp.

When the mains are disconnected the DC to AC Converter should be running.
240V should be available at the input to the relays.

Can you log in to it via the Computer Port and check for errors ?
In the pictures the leads from the two heatsinks go to a transformer.
This is likely to provide the 240V under Battery Power. Where do the output leads from that transformer go ?

[GT250]

UPDATE:
Well, it looks as though I've broken it

Even after I ordered the two relays (exact 100% same as the ones on the pcb), off feebay $USD$16...
I ordered them as I was testing the other relays were clicking away and the two that 'carried' the 240v to the GPO's didn't do anything as I was plugging and in-plugging stuff.

So now the UPS just beeps and auto turns off: As I was testing the opening and closing of the relays, I had the inverter cables unplugged at one stage and/or had those brn-blu cables unplugged... Anyway, after a fair amount of time I decided to order the relays and put all the cables back together.

It now turns on and then beeps and turns off... Behaves like nothing before (before it acted as though all was ok), now it's 'really' bad

Can't see the point of continuing with it. I'm not an expert, consider myself a base level hobbyist.

So I'd like to sincerely thank all that offered their help.

BTW: If anybody wants these relays free of charge, please let me know accordingly.

[eeprommemory]

i don't think you have broken it i have screwed with a lot of inverters and all have had the same problem.
remove all 4 battery's and connect a 12V H4 bulb with the low and high beam connected together and measure the battery voltage with the H4 bulb attached.
if the ups has CSB battery's shake the battery and if it rattles chuck it.

[Gitch]

Probably not too late, as Shred said and as I have posted previously for UPS' but number one rule for UPS's is change the batteries. They might appear to measure OK, but 98% of UPS faults are caused by the batteries being stuffed. I only ever previously used Yuasa batteries as I found them to be more reliable.

- I think you've been here before GT250

[BCNZ]

Agreed with the comments about the batteries. They are responsible for 99% of all UPS problems.

I was told by an APC service rep that there are issues with brands of battery as well, and I found this out after having problems with an APC UPS follow battery replacement.
I bought some generic branded batteries from my local security supplier and installed them. The UPS refused to start properly, and kept throwing up the battery fail light.
I took the batteries out and tested them - float voltage and load test, and all appeared fine.
Put them back in and the unit refused to play ball.

That's when I contact the APC guy, and he said "Try using genuine CSB batteries, you should be right with those".
So I took the generic batteries back to my supplier and swapped them for some CSB and returned home to fit them.
The UPS powered up immediately and showed no fault lights.
I have maintained this philosophy of only using CSB batteries.

Recently I was talking to another tech who deals with IT and UPS, and I told him about this problem of generic batteries.
"Rubbish" he replied. "I use generic batteries all the time in APC UPS and never have an issue".

So now I am starting to wonder whether the particular brand of generic batteries I bought that time were actually junk.
I haven't purchased any more of them, or any other generic batteries to find out!

I have had one APC UPS which had a faulty relay. When the power button was pressed, it would try to start, then there would be a loud
clunk as various relays dropped out, and all LED on the front panel would start flashing.

GT250: the issue with a lot of these UPS is there's no service data available (if it even exists) so you are really shooting blind and need
to have all your wits about you (because as someone else said, these things bite and it hurts if you don't watch what you are doing!)
The only way to test the relays is pull each one out and check their operation with voltage across the coil and resistance measurements
of the contacts. I have often found the contacts to be pitted, corroded or dirty meaning they won't switch properly, if at all.