Neutral bar for grounding


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Old 09-07-22, 01:34 PM
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Neutral bar for grounding

I am adding a 230V-2-wire sub panel for air conditioning adjacent to my main panel and fed from a 60A-2P circuit there. The panel has 4 slots and will have 2 20A-2P breakers. No room for expansion unless someone later wants to use some of those 1P/2P combination breakers. No neutral connections.

Any reason to NOT use the neutral bar for grounding? It will be bonded to the enclosure and will be connected with a bare ground wire from the main panel.
 
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Old 09-07-22, 01:43 PM
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Note that you can't use GFCI breakers in this panel since they require 120V. The minimum neutral size would be the same as minimum EGC, 10awg-Cu in this case.
 

Last edited by Luke M; 09-07-22 at 02:16 PM.
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Old 09-07-22, 01:47 PM
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As long as the bar is bonded to the case then it can be used for grounds.
 
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Old 09-07-22, 02:58 PM
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Luke:
can't use GFCI breakers in this panel
Being used for outdoor mini-split condensers that do not require GF protection.

Thanks PJ. ​​​​​​​
 
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Old 09-07-22, 07:30 PM
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Being used for outdoor mini-split condensers that do not require GF protection.
For the 2020 NEC, all outdoor outlets for dwelling units (with exceptions) that are supplied by single-phase branch circuits rated 150 volts to ground or less, 50 amperes or less, will be required to be GFCI protected. A mini split condenser is an "outlet" as defined by the NEC.

Note: 210.8(F) is not effective until January 1, 2023 for mini-splits.
 

Last edited by Tolyn Ironhand; 09-13-22 at 07:51 PM.
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Old 09-08-22, 07:35 AM
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Thanks for that code update information.

single-phase branch circuits rated 150 volts to ground or less
My units are 230V-1P so that does not seem to apply.
 
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Old 09-08-22, 08:01 AM
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My units are 230V-1P so that does not seem to apply.
The 2020 NEC gfci rule does apply to 230V. The 150V or less to ground pertains to each leg independently to ground.
 
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Old 09-12-22, 03:53 PM
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The 2020 NEC gfci rule does apply to 230V. The 150V or less to ground pertains to each leg independently to ground.
Can you provide the code section reference please. Thanks.

​​​​​​​Also, what is the code reference for access in front of the disconnect outside?
 
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Old 09-12-22, 05:21 PM
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NEC rule for gfci is 210.8(a).
 
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Old 09-12-22, 05:50 PM
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Also, what is the code reference for access in front of the disconnect outside?
The outside disconnect is only required to be "accessible".
 
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Old 09-12-22, 06:55 PM
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That is what I thought, but the HVAC contractor is asking for the 30 inch wide & 36 inch clear access. I suppose I will have to check with the inspection dept.
 
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Old 09-12-22, 07:23 PM
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I would not think the clearances rule would apply to AC disconnects because they do not require "examination, adjustment, servicing, or maintenance while energized." (NEC 110.26(A)(4)) All that is required of a disconnect should be to operate it on or off.
 
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Old 09-13-22, 08:09 AM
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Section 210 calls for GFCI for protection of personnel.
210.8(A) refers specifically to outdoor receptacles. My units are hard wired.
210.8(F) is not effective until January 1, 2023 for mini-splits.
 
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Old 09-15-22, 07:49 AM
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check with the inspection dept.
A visit to the chief electrical inspector this morning proved very fruitful. His interpretation is that if the disconnect contains overcurrent protection the clearance requirements in Section 110.26(A)(4) would apply. Otherwise the disconnect switch only needs to be "readily accessible".


Clearance from front of right hand switch to adjacent AC unit is 13 inches. As a minimum, just enough to be "readily accessible". The enclosure is similar to one that would house a circuit breaker (overcurrent protection) but in fact contains only a switch that looks like a breaker and is specifically labeled "No overcurrent protection." If it contained overcurrent protection he would require that it comply with Section 110.

Without getting into details that are only relevant to my particular situation, he also clarified an on-line permitting/inspection issue that was very favorable to me.
 
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Old 09-15-22, 06:16 PM
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FWIW I like the PVC conduit work, that's what PVC should look like with bends.
 
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Old 09-15-22, 06:27 PM
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His interpretation is that if the disconnect contains overcurrent protection the clearance requirements in Section 110.26(A)(4) would apply. Otherwise the disconnect switch only needs to be "readily accessible".
Makes sense to me. However, I have seen many disconnects with fuses that do not have those clearances.

FYI - I believe disconnects only need to be accessible, not readily accessible.
 
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Old 09-15-22, 06:56 PM
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[QUOTE]that’s what PVC should look like with bends.[/QUOTE]

Thanks. I have an old very powerful hair dryer that I use as a heat gun.
 
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Old 09-15-22, 07:02 PM
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/have seen many disconnects with fuses that do not have those clearances.
As I said—his interpretation.

He wasn’t overly enthusiastic about the location, so I may have added the “readily”.
 
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Old 09-16-22, 03:14 PM
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There is a TIA to exempt HVAC equipment from the GFI protection requirement. Some equipment has too much leakage to ground.
 
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Old 09-16-22, 03:15 PM
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The 2020 NEC gfci rule does apply to 230V. The 150V or less to ground pertains to each leg independently to ground.
The requirement does apply to 240 volt circuits.
 
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Old 09-25-22, 09:18 AM
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Project wrap-up and hindsight

The mini-split (cooling only) is up-and-running. Installed on Friday. Since then we have not had outside temperatures above 70 daytime and as low as 45 nighttime. Sigh...

While discussing equipment clearances I related to the installer the conversation I had with the electrical inspector about disconnect switches and overcurrent devices. He then mentioned that he was using a cheater cord to get power from the existing disconnect for his tools. (I did not press for details or investigate but can only imagine that he was tapping one leg and ground since there is no neutral there.) So much for not working on energized equipment. Or the GFCI receptacle 20 feet away (but not visible from the worksite.) Sigh...

In hind sight:

The original installation ten years ago was turn-key and I was not involved in overseeing the electrical portion. My electrical service is a fused disconnect switch and a fuse panel. I told the contractor that the 60 amp range circuit was unused and could be a source for the AC IF IT WAS FUSED DOWN! The contractor ran 12/2 from the panel to the disconnect and was supposed to replace the 60A fuses with 20A. When I looked for a power source for the new unit I found that the fuses had not been changed! Luckily no overcurrent events occurred in those ten years.

Since the original installation was 12/2 I assumed a 20A circuit was required and duplicated that for the new unit when the electrical spec only said 230v, single phase. It turns out that the manufacturer allows a 15A circuit as a minimum. I installed a new sub panel (fed from the 60 amp circuit) with 20A breakers due to the wire capacity.

The sub panel has no neutral since it serves only the mini-splits. However, if I had included a neutral, and if I had run 12/3 to the new unit I probably could also have installed a 120V GFCI outlet near the AC equipment to provide outside power on that side of the house.

Just some items others might consider for similar projects.





 
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Old 09-25-22, 10:27 AM
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I installed a new sub panel (fed from the 60 amp circuit) with 20A breakers due to the wire capacity.
The sub panel has no neutral since it serves only the mini-splits.
Using the 60 amp breaker to feed the sub panel is a great idea. However, I would have run a neutral to the sub panel for any future 120 volt circuits
 
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Old 09-25-22, 11:47 AM
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The sub panel is mounted to the side of the main panel. I bought the white wire for a neutral but did not install it because access to a large enough lug on the already full neutral bar was difficult. I'll just keep it nearby for future changes if desired.

I also relocated the feed from another 2-position box with a single pole breaker (GFCI for bathroom Jacuzzi) from the main lugs to the 60A fuses. It has 2 hots and a neutral and there is a spare position if I need another 120v circuit.
 
 

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