Intermitant voltage drop in detached garage

[dpoff]

Have noticed voltage dropping ocasionally, enough to bog down fridge and shut off TV. Plugged in a voltmeter to an unused recepticle and reads 115 volts. When the fridge bogs down and the TV shuts down the voltmeter drops to around 80 volts. This only lasts about a couple seconds and goes back up to 115 volts.It may happen several times within a few minutes or may not see it for quite awhile.
Any ideas?

 

[tpenfield]

My ideas are insufficient wiring or bad connections. Perhaps when the fridge compressor wants to turn on, it is causing the voltage drop (across the bad connections) and it kicks in and out as the voltage drops. Ca you leave the refrigerator off for a while and see if the problem goes away?

 

[Grub54891]

I'd be looking in the box, at both ends. Could be anything from to small of wire leading to the garage, or bad connections. Did you add more equipment lately? If there was a short,it should blow the breaker. Or is the fridge motor going south? A good clampmeter would tell ya at each source would tell ya where the issue is.

 

[dwco5051]

I think Grub is pointing you in the right direction. Could be the start relay or capacitor is going on the fridge. It acts like it doesn't get off the start windings and is cycling on the compressor overload till it finally starts. It might be hard to do in your situation but the fridge should be on a dedicated circuit.

 

[dpoff]

Thanks for the replies and good suggestions. I think first I will look at connections in the breaker box, then buy a clamp meter (I`ve always wanted one to go with my elec tools anyway.)

A couple of notes

-The fridge and the receptacle I tested with are on two different circuits.
- No new mods have been done to the system.
- Leaving the refrigerator off for a while is doable with just moving a few things into the house.
-Oh and Grub, I couldn`t fix it with a hammer!

I`ll start looking into this when I get back from family Christmas brunch.

Thanks again.

 

[Grub54891]

Lol... The hammer is the last resort....

 

[StarTed]

I think you have all good suggestions except for the hammer thing. How long is the wire run and what is the wire size to the detached garage? 115V is on the low side to begin with. Utility voltage in this part of the world is 120 plus or minus 5% meaning 6 volts. That used to be my job back before they began paying me to stay away. I take it you only have a 120V circuit to the garage, not 240 to a sub panel.

Pictures could help.

 

[bruceb58]

You should look to see what it is at the input to your main breaker switch. If it drops there, you need to call the power company.

 

[dpoff]

Thanks again. Got home late today. Plan on getting a clamp meter tomorrow and will start trouble shooting then.
When I got home, I checked on the fridge. It wasn`t running. I opened up the door and the light was off inside. Flipped a couple breakers and it started up. After about 15 minutes it bogged down a couple times but has been running good for about 30 minutes now but i`m sure that will not last.
Testing things tomorrow.
Thanks

 

[Scott Danforth]

Think it's a combination of your fridge is starting to go and the wiring is marginal

 

[Grub54891]

What size wire is leading to the garage? If to small it will cause things to overwork and cause them to go bad also.

 

[rbh]

You connected the wire to the main breaker panel bus bar? or did you tie it in at another point? was there anything else on that circuit?

 

[dpoff]

Found the problem today. A 30 amp quad breaker in the house that feeds the garage.
Being the issues were intermitant, it was really difficult to troubleshoot until it finally went out today.

Thanks for all the ideas