Effect of Low AC Voltage on Appliances

A1: high load on an undersized supply.

A2: stuff conks out.

A3: the fuse is there to protect the WIRING.

It sounds as if someone has installed a LynDoor Power Systems^® WattSucker G-6. These are wildly popular in countries and locales where energy is cheap and plentiful.

These are, unfortunately, not removable after installation. To restore full and proper operation, you may need to order the LynDoor™ Remedial Power-Mizer. Don't be fooled by the ridiculous claims of other manufacturers. There are many who are trying to copy us, but there is nothing like the original!

Before you place your order, there may be another possibility... where are you from (what country and region)?

Thanks for your replies buddies... I am living outside US and our standard here is 220V. That means our appliances are rated for 220V operation.

I am now calling an electrician to check our connection status. Loose connection is my first theory to the cause of low voltage at night.

My current AVR rating is at 500W, if I change it to 1000W, will the fuse stop busting out?

Yes, have your wiring connections checked by a licensed electrician. If the connections are ok, then the problem could be from your local electrical ultilty service.

Less than half the rated voltage? You have a serious problem.

Call a licensed electrician.Loose connections, or improper wire size is very dangerous, due to overheating issues, and unpredictable voltages at various places in the circuits, depending on what is turned on.Never increase fuse size to prevent a fuse from working.It is there for a safety reason.The reason the refrigerator blows the fuse is because of rotor lag. Not going into details,but the motor sees the low voltage as an increase in load, and current draw actually increases, causing fuse to blow out.

The reason the refrigerator blows the fuse is because of rotor lag. Not going into details,but the motor sees the low voltage as an increase in load, and current draw actually increases, causing fuse to blow out.

This is my theory too... Thanks for the idea...

Anyways, do you have any suggestion on an equipment that could help me compensate or protect my appliances for this sudden drop in voltage? Voltage is normal in daytime but low in night...

Voltage regulators are not designed to cope with 100V from 220V supply, about 30% down is all one can expect from the best types. I am surprised anything, except a filament lamp or kettle, still works at 100V if it is rated for 220.

A supply theoretically gives less than the maximum possible power at 100/220 of proper voltage - applying more current will actually reduce the power available - job for an AVR is very hard!

Such a value is far below what is tolerable and indicates severe overload or fault beyond what the supplier should allow for safety and "supply law" reasons.

If you need to protect appliances, an undervoltage cut-out on sockets (not lights) could be used. You would have to make one from a motor contactor and undervolt relay and put them into the socket supply circuit.

I agree, I doubt there is anything you can do to keep using your 220V appliances at 100V, your only option is to protect them by disconnecting them from the supply when that happens. In the case of your refrigerator, that means DON'T OPEN THE DOOR until your voltage returns to normal, or you will let out the cold air and spoil your food.