UPS not working on High Voltage

I am experiencing a problem with my UPS system from a couple of days. In our area, the voltage rises very high mostly at night. I know that the voltage is high by looking at the small LCD on my Homage UPS. It shows the input and output voltages.

Now I think there is some high voltage protection system in my UPS that whenever the voltage rises above 265 volts, the UPS cuts off from main line (WAPDA) and comes in backup mode. Backup mode normally kicks in when there is no electricity and UPS is taking power from battery to run home appliances.

Now although there is no load shedding but since the voltage is greater than 265 volts, the UPS does not come out of backup mode and hence battery keeps discharging. After a while UPS starts beeping due to battery discharge and the system shuts off.

I am attaching the pic below.

[sorry the picture is not uploading here]

In this picture, 285 volts is the input (WAPDA), 227 volts is the output of UPS for home appliances and the UPS is on Backup mode, means that it is not charging the battery, rather the battery is being discharged as it is giving power to home appliances.

Now what should I do in such scenario? Should I use a voltage stabilizer between UPS and WAPDA? Will it keep the voltage level in limits?

I already have a voltage stabilizer. It reads "Automatic AC voltage regulator with Servo motor". I have tried connecting it with UPS but it is not working. I have tried changing the direction of plug. In one direction it works when UPS on WAPDA but doesn't work on backup mode (The buzzer starts beeping and LCD reads "Fault"). In other direction of plug, it works on backup mode but doesn't work on WAPDA (The buzzer starts beeping and LCD reads "Fault"). Also even when it is in backup mode the voltage stabilizer keeps showing voltage reading. (At that time current is not flowing from Stabilizer to UPS, current is flowing from UPS to stabilizer)

Be safe and get a good electrician. Experimenting with power sources is not a good idea.


Thanks @neoclue for your reply.

Yes, you are right. The UPS wiring was done in a way that neutral is common for whole house where as positive (live) is connected separately to the appliances connected to UPS. This single wire is running superficial on the wall.

I think the Homage UPS is built in a way that you can not do double wiring for it.

Yes, I will call the electrician to solve this problem of connecting stabilizer.

About your question, yes our tv and fridge are burned once due to this high voltage.

Anyone else?


Even if you successfully install a voltage stabilizer at the input of your UPS, all other appliances at your home are still at risk.

Why not catch any IESCO guy and get your phase changed? This might get you out of trouble forever.

Do you have single phase or three phase connection at your home ?

I have three phase connection at my home.

^ and about your higher voltage problem, does it happen on all three phases in your home ?

1) If the loads in your home are not balanced (means not equally distributed on all three phases) then the phase with least load will have higher voltage problem.

2) If your neutral wire is not firmly connected (has a loose joint somwhere in the wiring, usually at main switch where it is connected to your home wiring), it can also cause high voltage problem and your loads will be at risk.

This is a little complex issue you are facing and it is really difficult to advise something before inspection; so better get some intelligent electriciana and get your connection checked first.

The voltage was not same for all the three phases. Some rooms had dim light and some had extra bright light.

Now the problem is solved. Other houses in our lane were also facing the same issue. So they had done some thing with the transformer and now everything is fine.


No, they haven't changed the transformer, it is the same transformer but they have worked on it for some time and solved the issue of high voltage.