GROUND to GROUND or NEUTRAL to GROUND in Fused AC Disconnect???

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jutasi

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Many solar installs exceed the backfeed rule for breaker panels, and thus require a client side line tap that connects to a FUSED AC DISCONNECT SWITCH.
I do inspection work for a few solar companies and one company has a crew that consistently connects the NEUTRAL of the FUSED AC DISCONNECT SWITCH directly to EARTH GROUND with the traditional #6 bare copper wire. It is my opinion that only the GROUND connection of the FUSED AC DISCONNECT SWITCH should be connected to Earth ground. Which is correct? Ground terminal to ground, or NEUTRAL to ground?
 
I have never seen an AC disconnect that had a neutral conductor, but in no case can the neutral be connected to earth on the load side of the service disconnect. 250.24(A)(5)
 
But he said line side tap. Where is this disconnect box? Between the meter and main distribution panel? If there, the neutral is both the grounded and grounding conductor, so it would make sense to me to connect the neutral to the enclosure with something sized per 250.66.
 
suemarkp said:
But he said line side tap. Where is this disconnect box? Between the meter and main distribution panel? If there, the neutral is both the grounded and grounding conductor, so it would make sense to me to connect the neutral to the enclosure with something sized per 250.66.
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Line is tapped inside the main breaker panel just above where the incoming utility lines attach to the breaker buss bars. From there, it goes to the outside of the home next to the solar inverter. This outside location is where they have been connecting the neutral line to earth ground. Only one of the installation teams does this. All the other teams connect the GROUND TERMINAL on the Fused AC Disconnect to earth ground. The installations all work fine, but I'd like to know the ULTIMATE CORRECT SETUP - one of the teams may be going to a installer competition in California in the near future, and I want to know that they will do the work properly, since it will be judged!!
 
If I understand the question, it's my opinion that the neutral in this switch should not be bonded/grounded here.
 
suemarkp said:
But he said line side tap. Where is this disconnect box? Between the meter and main distribution panel? If there, the neutral is both the grounded and grounding conductor, so it would make sense to me to connect the neutral to the enclosure with something sized per 250.66.
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I read "AC" as meaning air conditioning and as the AC disconnect for a the solar system :D

If this is a line side tap, then they disconnect is, while not called a service disconnect, really is for all installation purposes. This was cleared up in the 2020 code with a requirement that the line side solar disconnect be installed in compliance with 250.24(A) through (D).
 
don_resqcapt19 said:
I read "AC" as meaning air conditioning and as the AC disconnect for a the solar system :D

If this is a line side tap, then they disconnect is, while not called a service disconnect, really is for all installation purposes. This was cleared up in the 2020 code with a requirement that the line side solar disconnect be installed in compliance with 250.24(A) through (D).
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After reviewing 250.24(A) through (D) I see NOTHING that says the neutral should be tied to earth ground except at the main panel. Would you agree??
 
don_resqcapt19 said:
I have never seen an AC disconnect that had a neutral conductor, but in no case can the neutral be connected to earth on the load side of the service disconnect. 250.24(A)(5)
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You are correct, the typical knife blade (spring loaded or not) only switches L1 and L2. In the situation I describe, there is a neutral block, where neutral lines passing through the box can be terminated, which eliminates the need for any kind of wire nut, or splicing device. This is the location that is being connected to earth ground. I've attached a PDF photo to another of the responses that you may inspect to see what I'm talking about.
 
jutasi said:
This is the location that is being connected to earth ground.
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There's no reason to; that electrode connection is made in the main disconnect.

They certainly can add an electrode to the EGC connection if they like.
 
LarryFine said:
There's no reason to; that electrode connection is made in the main disconnect.

They certainly can add an electrode to the EGC connection if they like.
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LarryFine said:
There's no reason to; that electrode connection is made in the main disconnect.

They certainly can add an electrode to the EGC connection if they like.
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I agree. If they feel compelled to add additional grounding, it should be to the GROUND wire coming from the main breaker panel, and landed on the ground terminal in the Disconnect housing.
 
Can I see a picture of the disconnect lid. Curious on your labeling. In the pic which pipe goes to the line side tap. Any dead front rules apply since this is tap ahead of service disconnect. Time to read up on 2020. Would the fuses being back be hot if switch was open. If so that could be bad. Thinking it was dead on the load side. Does the array shunt when switch is open. May be safer if it was circuit breaker enclouser.
 
Hard to see in pic does the electrode conductor terminate on the netutal bar and is there a mbj (screw) used . Can not see the green in the pic. If so is that a service rated disc?
Just curious
 
I'm on 2014 and have read 690.16
Does same rule apply to 2020.
690.13(c) does not require to service rated however this is a line side tap with an electrode.
690.17 (E) waring lable
 
Thinking out load.
If service rated not required. Than green mbj screw not required to be green. Maybe a better term would SBJ screw at that point. Not required to be green? If so a SBJ could be wire type and not be required to a factory type.
 
Tulsa Electrician said:
Can I see a picture of the disconnect lid. Curious on your labeling. In the pic which pipe goes to the line side tap. Any dead front rules apply since this is tap ahead of service disconnect. Time to read up on 2020. Would the fuses being back be hot if switch was open. If so that could be bad. Thinking it was dead on the load side. Does the array shunt when switch is open. May be safer if it was circuit breaker enclouser.
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those are some interesting comments, but everything shown here is done DAILY by THOUSANDS of installers nationwide. It is a STANDARD QUICK DISCONNECT SWITCH. Incoming side is hot always. My concern is about GROUNDING. You can form your own opinions about the rest. Thanks anyway!
 
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