Cyberpower PR1500 won't charge battery

[budm]

Re: Cyberpower PR1500 won't charge battery

The VIPER has internal charge pump circuit that charge up the 22uF startup/running cap, when the the VDD reach the startup Voltage point to get the VIPER running then the charge pump stops then the VDD get the running Voltage from the AUX winding.
That protection Zener D23 is not needed for the VIPER to run, it is for protection in case the VDD goes up to high, typical Voltage for that Zener is around 22V.
The diode and the 50K resistor and the the cap are for the RCD snubber circuit (R1/D1/C2 in the example circuit as shown in the spec sheet).
From VIPER22 spc sheet page 6/20
Power supply of the control circuits. Also provides a charging current during start up
thanks to a high voltage current source connected to the drain. For this purpose, an
hysteresis comparator monitors the VDD voltage and provides two thresholds:
- VDDon: Voltage value (typically 14.5V) at which the device starts switching and turns
off the start up current source.
- VDDoff: Voltage value (typically 8V) at which the device stops switching and turns on
the start up current source.

[reberhar]

Re: Cyberpower PR1500 won't charge battery

Hi Bud,

I just measured the aux winding. The D25 is providing 12.5 volts DC. This goes to the optocoupler and then to the Feedback pin. The D23 is connected then to the negative side of the aux winding and then down onto the VDD.

So I am trying to wrap my mind about this. This means that the negative side of the aux winding is providing the power for the SMPS as you call it. Since there is no center tap on the aux winding that means that ground is coming through the SMPS. There should be 12.5 volts on the negative side too, although I read nothing when measuring the aux negative tap on the AC of the VOM. Otherwise how can the SMPS turn on? My reference is on the negative pin of the filter capacitor.

I will read your post again about the zener.

I have repaired lots of digital stuff over the years, analog not so much. Usually though, if I am patient I can get these too.

Thanks,

Roy

[reberhar]

Re: Cyberpower PR1500 won't charge battery

Hi Bud,

Thanks for the help. Any suggestions on which zener? I can read the spec sheets to I guess.

You are a wonderful resource.

God bless you,

Roy

[budm]

Re: Cyberpower PR1500 won't charge battery

This is what I see based on your pictures, see the attached marked picture,
D23 22V ~ 24v 0.5W ZENER should be OK.
The circuit in the spec sheet left out the protection Zener, most of them do not use it to save money.

[reberhar]

Re: Cyberpower PR1500 won't charge battery

I ordered some 22 Volt units as per your first suggestion. The 1500 had 24 volt units. 22 should be ok though.

Roy

[reberhar]

Re: Cyberpower 1350AVR wouldn't charge battery - but does now.

Hi Bud,

Thanks for the annotated graphic of the circuit. It does indeed charge without the zener. I am at 27 volts which seems a little low. I am going to change some diodes and the filter cap in that circuit. If it was a lightening strike those could have been compromised. Checking the with scope shows no ringing so perhaps it is a diode or perhaps it is totally normal. I need to let the batteries finish charging.

Your patience is outstanding and your help has been great. I would shake your hand, but I can't reach the west coast of the US from Oaxaca Mexico.

I hope helping is as rewarding to you as it is to the rest of us.

I do similar work everyday helping Bible Translators with their computers, managing the servers and firewalls and yes fixing hardware. It is exhausting. If you get as tired as I do then may God bless you with rest.

Roy

[budm]

Re: Cyberpower PR1500 won't charge battery

The charging Voltage for your two batteries connected in series should be around 13.75 x 2 = 27.5V so you may be OK, I would connect the batteries to the unit and let them charged up over night, no need to turn on the UPS since the charging circuit is running 24/7 the minutes the UPS is plugged into the AC outlet.

https://www.powerstream.com/SLA.htm

[reberhar]

Re: Cyberpower PR1500 won't charge battery

Hi Bud,

Since charging is a current operation it is a little hard to tell. However, I am up to 27.2 so that is a good sign. The batteries are connected and seem like they are warming a little. That is also a good sign. I will let you know how things look tomorrow when they have charged overnight.

Roy

[reberhar]

Re: Cyberpower PR1500 won't charge battery

Hi Bud,

So we are not looking at 14.2 x 2 or 28.4 like lead acid batteries in a car. Gel cells want 13.75 times x 2 or 27.5. At this point I am at 27.3. which is pretty good.

Roy

[reberhar]

Re: Cyberpower 1350AVR won't charge battery

Looks fixed. Battery is at 100%. I have been using batteries from another unit. I have also ordered replacement batteries as the others were bad. I found a 24Volt Zener locally which I will install today.

[budm]

Re: Cyberpower PR1500 won't charge battery

Thanks for the follow-up on the repair.

[reberhar]

Re: Cyberpower 1350AVR won't charge battery

[cyberlander]

Re: Cyberpower PR1500 won't charge battery

I can do that. I haven't tested anything further. Forgive me, but I'm more of a software and digital guy...

If you let me know what I would need to test (ie: look for chip x, which should run to cap X and measure the output, etc) I can do it and report back.

thanks,

-jr

Hi Jr219,

Did you ever resolve the issue with your UPS? I have the same board with the same issue. Thanks

[jr219]

Re: Cyberpower PR1500 won't charge battery

Hi Jr219,

Did you ever resolve the issue with your UPS? I have the same board with the same issue. Thanks

I have not. It's still on the bench. Not sure if I should replace that one cap or not. Considering just purchasing a new one as sad as that is.

[alphatango]

Re: Cyberpower PR1500 won't charge battery

Just opened up my PR1500LCDRT2U because it wouldn't start up. Battery was voltage was 26V but the charging leads couldn't hold steady voltage on the multimeter. The cause looks like 2x 63V 2200uF leaking caps in the back left corner of the board. I've never done a cap replacement before but I'm going to try!

[budm]

Re: Cyberpower PR1500 won't charge battery

See post #17 and read the follow-up posts.

[okto]

Re: Cyberpower PR1500 won't charge battery

hello, my name is Frank, BUDM can you help me please... I have right now the same problem. The UPS won't charge the battery... I have a UPS Cyberpower model CP1500AVR... The Battery are New......Dou you have the service manual for this equipment ? Thanks very much for all.

[budm]

Re: Cyberpower PR1500 won't charge battery

hello, my name is Frank, BUDM can you help me please... I have right now the same problem. The UPS won't charge the battery... I have a UPS Cyberpower model CP1500AVR... The Battery are New......Dou you have the service manual for this equipment ? Thanks very much for all.

Is your board the same as in my post #17? If it is then read post #17 and later to know which caps to replace.

[kitts]

Re: Cyberpower PR1500 won't charge battery

OK, replace C40 (100uF 25V) startup cap, you should also replace the output filter caps C44, C47 (100uF 63V), C45 (47uf 50V) at the same time.
Replace C40 will make the charger circuit work again.
Use good caps such as Panasonic FM/FC/FR series from Mouser or Digikey.

Thank you. Followed this and replaced all 4 caps and now my PR2200 is fully functional!

[electronicsuk]

Re: Cyberpower PR1500 won't charge battery

Hey guys. I've had a similar issue with my CyberPower OR1000ELCD not charging the batteries, ultimately discharging them to the point thay the UPS wouldn't even power on with mains present. I was almost going to ditch it after already having wasted money changing the batteries, but finding this thread gave me some hope.

As removing the PCB was a bit of a pain and not something I wanted to do twice, I ended up replacing almost all of tjr through hole caps on the board, along with the Viper 22A, TIP42C and the two LM series voltage regulators.

Good news is that the UPS powers on now and I have 27V open circuit at the battery terminals. However, with the batteries connected and an ammeter in series, I can see that the charging current climbs to about 600mA for a couple of seconds, drops off for a few seconds, and repeats ad infinitum.

I know that the batteries are good, having charged them fully from a bench PSU and then running them down while load testing the UPS. I've noticed the Viper 22A runs extremely hot. I've also noticed that after leaving the UPS off for a minute or two, I get continuous charging current for about 10 seconds before the stop/start cycle begins. This all leads me to suspect the Viper 22A is going into thermal shutdown.

As it sounds like the PR1500 and OR1000 share a common charger design, have any PR1500 owners measured the charging current of their UPS into a discharged battery? Assuming the US and EU models are common, the Viper will be set up for wide input voltage range. According to the datasheet, the DIP8 model is only rated for 12W in wide range application. I'm seeing 600mA at 25V, which is 15W - this could explain the Viper going into thermal shutdown. I'd like to know if this is "normal" behaviour (i.e. the charging system is just badly designed), or if I have another fault to find.

I suspect eventually the batteries will charge up, the charge current will decrease and the Viper will come back into limits. That being the case, the UPS might have worked this way from new - I've never had cause to measure the charging current until now and I only own one UPS so can't compare to another working one!