Another Electrical Question

[C(-)ris]

The power stopped working out in my garage when the wife was using the air compressor to fill up tires. Lights and outlets are on one 15A breaker.

I checked the fuse and it wasn't tripped. GFCI also wasn't tripped.

After turning off the breaker, I opened up the electrical junction box and when I pulled out the wire jumble a few of them came loose from the wire nuts.

I separated all the wires and isolated the feed from the house. It is a 4 wire cable. Red, Black, Grey, and a copper ground.

Flipped the breaker back on and I have 120V on Red to Grey, but only 14V on Black to Grey. Red to Black gave me 106V. I believe the red cable was capped off by itself and wasn't being used previously and the Black was my hot but isn't working correctly now.

I capped off the black and used the Red for hot, white for neutral, and ground for ground and was able to get power working in my garage again for now and verified voltages were correct and used the outlet tester to verify everything was hooked up correctly.

My question is, what happened to my original feed? And, why did I have two hots going out there in the first place? There is only 120V service to the garage and a 120V breaker.

Not sure where to go with this now, I could just leave it as is, but I'm really curious about what happened and why I have two hots.

[Filliam H. Muffman]

Did you have anything plugged in to the circuit when you got the 14V/106V reading?

[C(-)ris]

Filliam H. Muffman wrote:
Did you have anything plugged in to the circuit when you got the 14V/106V reading?

Nope. I had the wires coming into the garage separated completely from the rest of the circuit. I've followed that line and as far as I can tell it runs from the breaker box, along the ceiling in the basement and then goes into conduit out the side of the house under ground and over to the detached garage. The junction box is right above where it comes out of the ground.

[space-time]

..the wife was using the air compressor to fill up tires.

this is the problem. Men should fill tires.

[Speedy]

They pulled the original wire because code called for 240v to a garage but there was no requirement to have an actual 240v outlet in the garage. It future proofs things. You can verify code by calling the inspections office. You can ask your question in a manner that would imply you are just getting some thoughts together on what you might want in an eventual garage.

[mikebw]

Speedy wrote:
They pulled the original wire because code called for 240v to a garage but there was no requirement to have an actual 240v outlet in the garage. It future proofs things. You can verify code by calling the inspections office. You can ask your question in a manner that would imply you are just getting some thoughts together on what you might want in an eventual garage.

This makes sense, but I was going to suggest that generally a 4th wire is used for 2-pole switch arrangements, where you might have two separate on/of switches controlling the same outlet or fixture for example.

[The Grim Ninja]

What's it look like in the circuit panel?

[C(-)ris]

The Grim Ninja wrote:
What's it look like in the circuit panel?

Haven’t opened the box yet. I had standing water in my basement until last night and I wasn’t about to open it up with water on the floor.