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voltage sag/ lights dim/UPC-battery backup clicks

I have been experiencing lights flickering momentarily for several years one or two times a day. It became more evident when I hooked my computer and tv to seperate UPC battery backups last fall. Now the UPC will click when the lights flicker. I have had the power company check the incoming line, tighten the incoming wires to my 400 amp distribution box and put on a recording meter which showed what they call a minor (114 to 124) fluxuation in the voltage. I have had an electrician tighten the wiring in each of my two distribution panels. Both the electrician and the power company thinks it may be the 240 heat pump. However the drop in voltage as measured when the heat pump came on was 5 to 6 volts over 5 to 10 seconds. What I am experiencing is a voltage fluxuation of less than a second. The voltage dip or sag also occurs in the evening after the heat pump shuts off or during times of low temps when the furnace is using propane back up.

The outdoor transformer is relatively new and is rated at 50kv? and serves 5 houses. One of my neighbors says they also experience a sag, the others don't notice it. Two of the neighbors have new heat pumps. I also have a small spa heater that goes on and off and a septic pump motor (but I can hear when the septic pump goes on and it does not coincide with the sags).
The house wiring is installed in 1974.

I hope I have given enough information for some one to say " aha I know the answer"! Thanks in advance for any help you can provide. :)

djohns
Re: voltage sag/ lights dim/UPC-battery backup clicks

A couple of things jump out at me . You say that you have a 400
amp service ? You're being served by a 50kva transformer ALONG WITH four other customers ? Depending on the load of these other customers , that could be problem . One of your neighbors could be the source of the " dip " . I think your answer is going to be found with the assistance of the power company , you're just going to have to find the right person to complain to .

Fencepost
Re: voltage sag/ lights dim/UPC-battery backup clicks

If a heat pump was the source of the problem, I'd expect it to happen more frequently. Does one of your neighbors by chance have a large air compressor that they leave turned on? As air slowly leaks out, it will need to restart every once in a while to pump back up. Twice a day seems like it could be a common frequency for this sort of thing. You'd notice it more often if they were using the air.

I do computer consulting for work, and we've got one customer (a business) who, every 59 minutes, experiences a voltage fluctuation. It affects their computers in that the computers lock up during this time. We've been unable to find the source of the problem, and we've had to tell them that it's an electrical problem and outside the scope of our business.

NEC
Re: voltage sag/ lights dim/UPC-battery backup clicks

One problem with the internet and these forums is that you never really know the qualifications of those that reply.

I can tell you this. Though he is reluctant to toot his horn dj works for an electrical utility and his advice has always been sound............. You may want to consider his post as your "jump out" and follow that track.

Personally, I am looking forward to some southern cooking ;)

djohns
Re: voltage sag/ lights dim/UPC-battery backup clicks
NEC wrote:

One problem with the internet and these forums is that you never really know the qualifications of those that reply.

I can tell you this. Though he is reluctant to toot his horn dj works for an electrical utility and his advice has always been sound............. You may want to consider his post as your "jump out" and follow that track.

Personally, I am looking forward to some southern cooking ;)

You flying or taking the bike ? :D

Vern Smith
Re: voltage sag/ lights dim/UPC-battery backup clicks

You said the power company saw a 10V drop on the recorder. They should have also recorded current to see if it is your load causing the drop or someone else on the same transformer. Ask 'em to come back and record BOTH amps and volts on each leg. Might save you chasing a problem that belongs to somebody else.

kevingreen
Re: voltage sag/ lights dim/UPC-battery backup clicks

Hi guys,i met some problems with my UPC and i don't know if is my UPC's battery bad or the UPS? I've got an out of warranty Belkin 1200VA uninterruptible power supply. It stopped holding a charge, meaning with it unplugged while items are plugged into it, the items have no power. A UPS should provide power to items plugged into it. Often, the solution is simply to replace the battery. But before I order a new battery, I want to make sure such will fix it.

So I used a digital multimeter to measure the output voltage on the battery. I set the multimeter voltage to 200. Touching the multimeter probes to the pos and net battery contacts, I get a readout of 26.8.

The Battery is a Ritar RT1250 and the label says "12V 5.0AH/20HR Valve Regulated Rechargeable Battery. Constant Voltage Charge. Cycle Use 14.4-15V. Standby Use 13.6-13.8V. Initial Current less than 1.5A."

Is this battery good, meaning the UPS unit has gone bad? Or is the battery bad?

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