[Vgama]

Hello

I would like your help for solving a malfunction in UPS Mustek 600 VA Plus.

In the beginning the UPS was completly death.

I change the batery and it starts working.

I let it be 10 hours for a complete recharge.

At the end everithing was working normally - output was 230V

Then I make a test removing the ac cord 230V to simulate a power loss.

Result - the output came down to only 150V and should maintain 230V.

I test the voltage on the batery and only have 13.5V and never rise to 14,5V even on normal operation.

Has I don´t have the schematic, I would like your help to solve this problem.

Thank you

[SNi]

Vgama, on 01 February 2010 - 02:21 AM, said:

Hello



I test the voltage on the batery and only have 13.5V and never rise to 14,5V even on normal operation.

Has I don´t have the schematic, I would like your help to solve this problem.

Thank you

In this kind of device voltage may be quite low. 14,5V is little bit high voltage with batteries nominal voltage 12V. Batteries should get fully loaded even with 13,5V. Have you measured voltage when you take power cable off?
If it drops very much your battery doesn't give enough power or your UPS wastes power somewhere.

[sivankls]

Vgama, on 01 February 2010 - 02:21 AM, said:

Hello

I would like your help for solving a malfunction in UPS Mustek 600 VA Plus.

In the beginning the UPS was completly death.

I change the batery and it starts working.

I let it be 10 hours for a complete recharge.

At the end everithing was working normally - output was 230V

Then I make a test removing the ac cord 230V to simulate a power loss.

Result - the output came down to only 150V and should maintain 230V.

I test the voltage on the batery and only have 13.5V and never rise to 14,5V even on normal operation.


Thank you

I think u're measuring the output of UPS with an ordinary digital meter..since the output is seldom sinewave for such low cost UPS u need to measure its output with an analogue or true RMS meter..the battery voltage to me is OK..Normally for UPS with an in build battery 13.8 ~ 14.0 is ok.

[Vgama]

sivankls, on 09 February 2010 - 07:31 AM, said:

<br />I think u're measuring the output of UPS with an ordinary digital meter..since the output is seldom sinewave for such low cost UPS u need to measure its output with an analogue or true RMS meter..the battery voltage to me is OK..Normally for UPS with an in build battery 13.8 ~ 14.0 is ok.<br />

<br /><br /><br />

Thank you por your help

I change the IC LM317T responsable for charging the batery and everything works fine now.

Thanks again