Re: CyberPower 1350AVR - Repair

I solved my problem by purchasing an APC SMT1500RM2U from ebay and putting my new batteries into it. Working perfectly. I couldn't figure out why the other 2 units from Cyberpower weren't working. After replacing all 3 caps and Viper chip, plugging them into AC resulted in power to the surge protected side but no power at all to the battery side.

Even though I did not fix my problems I appreciate all of you for your help and information. Hopefully someone else can make use of the information presented here in the future. Thank you.

Re: CyberPower 1350AVR - Repair



I tested the new batteries with a 12v DC fan attached, each read 5v to 6v, seems that having them in the first unit for a couple days almost killed them. Or they came from the store like this. I have one on the charger to see if it can be revived.

I tested the batteries from unit 2 and they read 12v to 13v, so seem to be fairly healthy despite being 7 years old. Obviously the batteries were not the problem for unit 2 as it did not switch power over to battery when the AC went out.

Is it safe to test the...

Re: CyberPower 1350AVR - Repair

I decided to work on my second unit. I took it apart and looked at the board, no visible damage that could be seen with the eye. I tried the new batteries in my second unit and without AC power, turning the unit on lit the LCD and power button up blue but there was no words on the LCD.

Plugging the unit into AC power, plugging in a fan into the battery side, allows the fan to run but when unplugging the unit from AC, the battery backup does not kick in and says overloaded on the LCD with battery at 0% and the fan turns off. A constant...

Re: CyberPower 1350AVR - Repair

Well, I have damaged my circuit board, as I knew I would. I should hang up my iron before I hurt any more boards.

I had to turn up my soldering iron to 450 instead of 350 in order to desolder the parts off the board because the solder did not want to melt. The solder wick did not want to suck up the solder either. Somehow I managed to break free a pad from the board for the Viper22. It didn't come off all the way and I managed to put it back but I knew it wouldn't work.

After putting everything back together, I plugged...

Re: CyberPower 1350AVR - Repair

Thanks, I knew there were a lot of people using the Hakko when I bought it years back but I was soldering like a plumber with bad solder and acid flux which gave me poor results. I was also using too high of temperature. My hands also shake a lot, so that doesn't help. After watching hours of good informative videos and purchasing real solder and flux I think I'm ready to do much better.

Great tip on cutting the pins on the chip, I saw this done in a video too.

I was going to put some heatsinks on the viper's but after...

Re: CyberPower 1350AVR - Repair

Thank you for the information Behemot, I appreciate it. I don't look forward to replacing capacitors or anything requiring soldering as even though I have done it before, I am not very good at it. It looks like C3 and C6 need replacing as well as the Viper. C1 looks fine but I should probably replace it also as others have had problems with it. Are there any others that you would replace? I hope not, it's going to be a chore for me to replace the ones I have. I found a Viper at DigiKey, [url]https://www.digikey.com/product-detail/en/stmicroelectronics/VIPER22ADIP-E/497-7694-5-ND/1852690[/url]....

Re: CyberPower 1350AVR - Repair

I have a 7 year old Cyber Power 1350AVRLCD UPS. It was time to replace the batteries so I bought 2x PSH-1280F2 and replaced them inside the unit. I turned the unit on, it started beeping like normal. I turned it off and decided to plug it in and let it charge so I could see if it was going to work. As soon as I plugged it into the wall, puffs of smoke came from the unit and I unplugged it and took it outside.

After opening the unit I saw 2 bad caps. It looks like the same caps that are being referenced here. I was told this was a good...