Hello- first time poster here from Ontario, Canada.

I'm attempting to take on my first electrical job around the house with a new light fixture in the kitchen. After seeing many how-to videos online, I was immediately overwhelmed with the additional wires in this junction box:

There are 4 ground wires capped at the top (see pictures below) and the old fixture's ground wire was *not* connected to them. The new fixture has two ground wires to connect, however it proved very difficult to connect them with the other four in the nut (which clearly seemed too small)

1. Why are there so many ground wires in this junction box?
2. Do I need to connect the new fixture's ground wires to these 4 wires? Do I need to purchase a larger wire nut?
3. What are the hot/neutral wires connected (with the large black nut in the center of photo#1) used for? Should these be in the j box in the first place?

Thanks
-Peter

 

Maybe I'll solve my own problem here:

Is it OK if I take any one of the ground wires out of that cap (top of photos), bring it down and wrap my two ground wires from the fixture to that, with a new cap?

 

No, all the ground wires, including the one(s) from your fixture need to be tied together. Use a larger wire nut if necessary. You could separate into two bundles, but would then need to add a wire connecting the two bundles so it probably makes more sense to just get a bigger wire nut.

It's common for fixture boxes to be used also as junction boxes with a power in connection and then one or more connections going to other fixtures or receptacles. That explains the other hot and neutral wires. Another reason for multiple wires in a fixture box would be use of three way switches.

 

Welcome to the forums.

Nothing out of the ordinary in that junction box. You have four cables there so you will have four ground wires. Pretty straightforward.

You have four cables there.
One cable brings power to that box. That is feed in.
Two cables bring power to other other boxes..... those are called feed out cables.
The fourth cable is a switch loop. Power is brought to the switch on the white and returned to the box for the light on the black.

DO NOT change any of the connections.

The white fixture wire goes to the all white splice.
The black fixture wire goes to the single loose black wire.
The ground wire connects to those four bare wires and the wirenut looks plenty big enough in the picture since there is no insulation to cover. If it needs to be a larger one.... change it out.

 

Try a big blue wire nut on the ground.

Here is approximately what you have though maybe even more load out cables. Note if it was wired to standard convention the white to the switch is with the blacks and the black of the switch loop cable goes only to the light.

 

Thank you Ray, PJ, and CarbideTipped for the incredibly helpful information! Managed to fit the fixture's ground wires nice and snug with the same cap.

Got it up this morning with your assistance! Your help is much appreciated.

 

Good job. Thanks for letting us know.