awitowsk Posted February 21, 2009 Report Share Posted February 21, 2009 Quick question. I picked up a 50 amp GFCI spa box and want to wire it 220. I thought there was supposed to be one bar for the ground and another for the neutral hookup, this box has just one bar. Do I just hook both up the neutral and ground coming from the main box ground bar to the bar in the spa box, then also the white pigtail and the ground out to the spa? Thanks, Alex Quote Link to comment Share on other sites More sharing options...
hot_water Posted February 21, 2009 Report Share Posted February 21, 2009 Quick question. I picked up a 50 amp GFCI spa box and want to wire it 220. I thought there was supposed to be one bar for the ground and another for the neutral hookup, this box has just one bar. Do I just hook both up the neutral and ground coming from the main box ground bar to the bar in the spa box, then also the white pigtail and the ground out to the spa? Thanks, Alex Hi Alex, No, don't do that. Your GFCI won't work properly - it will either trip instantly or never trip, ground fault or no. It looks like the ground bus strip is in the lower right hand corner, behind the coiled neutral coming from the breaker (called the "pigtail"). Check continuity between this strip and the steel case (make sure you go through the paint or find a screw head that threads directly in to the box) before connecting anything else. If the case and the bus bar are connected, that's your ground bus. The ground bus gets the green coming in from your house panel, and the green going out to the load (spa). Check your local code. I think that, due to a fairly recent change to the code, ALL sub-panels now require a separate ground rod, which you can buy at Lowe's or Home Depot along with the screw clamp fitting to connect up the ground wire. Pound the ground rod, which is usually required to be 6' long copper or copper-plated steel, 5/8 diameter in my area, all the way into the dirt. As you can imagine, it starts off easy but that last two feet is a real pain. And it's no fun when you hit a rock. This wire from the ground rod also connects to the ground bus bar. I use a piece of armor-flex cable (with appropriate fitting) to to protect the ground wire. The sheath of the armor flex has to make ground contact with box. The red & black leads from the house panel attach to the lugs at the top of the bus structure. The bus strip that the coiled white pigtail is connected to is the neutral bus. Leave the pigtail conected and connect the white wire coming from the house panel to this strip. The three wires (red, back & neutral) going to the spa connect to the three positions on the breaker. You shouldn't ever connect the green to neutral EXCEPT back at the house main panel. Your meter will show they are connected because they are tied together at the house panel. Did you buy this box new? It should have come with a wiring diagram. or sometimes the diagram is stuck on the inside of the box cover. Hope this helps, -hot_water Quote Link to comment Share on other sites More sharing options...
awitowsk Posted February 21, 2009 Author Report Share Posted February 21, 2009 Thanks. Obviously I spent way too long working outside last night and was a good thing the wife pulled me inside to call it a night. I didn't see the ground bus behind the pigtail last night. This morning I got up and it was obvious. I had read to pull the ground from the main panel and not to run a ground rod. Are you suggesting pulling the ground from the house and also running a ground rod to the ground bus, or just a ground rod? Quote Link to comment Share on other sites More sharing options...
hot_water Posted February 21, 2009 Report Share Posted February 21, 2009 Thanks. Obviously I spent way too long working outside last night and was a good thing the wife pulled me inside to call it a night. I didn't see the ground bus behind the pigtail last night. This morning I got up and it was obvious. I had read to pull the ground from the main panel and not to run a ground rod. Are you suggesting pulling the ground from the house and also running a ground rod to the ground bus, or just a ground rod? Depends on the local code. IF the subpanel rod is applicable in your locality, you need both. A call to the inspector should answer the question of "do I need this". He may ask you about your installation, other metal pathways to the deck, type of conduit used, etc. Just adding a ground rod alone without tying back to the main panel ground would be *seriously unsafe* in my opinion. Do check with the inspector. Grounding is as much tied up with local codes as with the NEC, and has to do with, whether there are other ground paths to the main house, whether your deck is attached... and probably more. There seems to be some disagreement even between electricians as to whether the ground rod is required, and inspectors aren't infallible, either. But you need to get a reading on this, since it's safety related. -hot_water Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.