I'm trying to add a 30amp, 110V RV connection box to my house but the service box has no neutral bar, what do I do with the white neutral wire?

This is a picture of the main panel by the meter.

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This is a picture of the garage sub panel where I will be adding the RV service box.

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It appears as though you have four slots available at the garage panel on the left side of the panel in your picture and one in the upper right.

The neutral bar is on the bottom of your picture with the white wires.

What seems to be the problem?

  • Thanks ArchonOSX, so my ground bar is the one next to the neutral bar? Even though they are both tied together? – johnnychingas May 4 '16 at 16:12
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    Yes they are both tied together at the service by the "main bonding jumper". This is the only place in the electrical system where the neutrals and equipment grounds are allowed to be bonded together. So the panel in your garage is a sub-panel and the neutral bar must be isolated from ground. That is why it is mounted on plastic. That panel could have a ground bar added to it. You could look for an add on ground bar kit for your panel. At the sub-panel the grounds and neutrals must remain separate. – ArchonOSX May 4 '16 at 19:52
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    Your panel appears to be a very old Square D QO style panel. QO breakers should fit it. If you add a ground bar you will have to drill and tap the panel to mount it. It should be tapped for a finer thread screw like a 10-32. – ArchonOSX May 4 '16 at 19:59

You have a neutral bar. You don't have a ground bar. Your panels look exactly like mine, which feed all EMT metallic conduit, and the conduit is the ground path. Care for it kindly, fix gaps immediately.

Your main panel has a neutral bar which appears to be all-metal and by nature bonded to the panel box (which is ground), which is both allowed and required in a main panel.

Your sub-panel has a neutral bar which is insulated from the panel box aka ground, which is required in a sub-panel.

Beware, on an isolated neutral bar, there are often special screws, usually green, which screw through the neutral bar to bond it to the case (ground). You should take care that there are none of those on a sub-panel; on a main panel I would "belt and suspenders" that by also adding a bonding strap.

  • Thank you Harper, I understand it now, thank you all for your answers. – johnnychingas May 5 '16 at 4:13

I see both a neutral bar and a ground bar strapped together with jumpers. I also see the required ground wire. There is nothing wrong with this installation other than the panel having very few breaker slots.
You need a dedicated 2 pole breaker to connect a sub-panel to the main. Its amp rating should not exceed 50% of the main breaker rating. You can do what you want as long as you run another white neutral wire and ground wire back to the main panel.
The breakers in any sub-feed panel cannot exceed the rating of the sub-feed panel main breaker.

NOTE: If the main panel does not have any spare breaker slots, you will have to shift the wires to any 240vac device to your new sub-feed panel, or buy a whole new panel.

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