Service Rated Automatic Transfer Switch Grounding

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Bonham Electric

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Sacramento, Ca.
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Electrician
The existing Meter/panel combo is a 200Amp rated Crouse Hinds underground fed with No 200 Amp main. The panel was factory wired from the load side meter jaws, with 3/0 copper to main lugs, feeding a buss with provisions for two double pole breakers. Existing is a 100 Amp 2 pole, feeding the mian sub panel and the other breaker is a 60 Amp two pole, feeding the condenser. Factory bonding consists of a ground buss, where the main neutral from the utility lands in the Utility section. The buss extends horizontally across the Breaker side and is factory bolted to the enclosure with 4 lugs, where the (2) #4 grounds land ( 1 is cold water, the other is a Ufer). The only neutral is the #2 Awg that is in a #2-3 romex and feeds the sub panel. We connected the service rated ATS with 2"EMT conduit and a 2ft piece of steel flex. A ground bushing was installed in the ATS where the #4 Green stranded was attached to the bushing lay in lug and then to the ground buss in the ATS. The feeders consists of (4) #2/0 locomotive cables ( 2 for utility, and 2 for load).The generator is a 24KW and produces 100 Amps. We installed a #2 white from the Main ground/neutral buss in the meter panel to the neutral buss in the ATS. The inspector had my tech add a jumper in the ATS from the ground buss to the isolated neutral buss.
As mentioned- The existing service required that You turn two double pole breakers off to kill all power to the house. With the New configuration, there is now a 200 Amp Main in the ATS. The ATS is mechanically connected with steel EMT and Flex with all steel fittings and bonded with #4 thhn and this ground is to the same buss where the original grounding is terminated. We also have a #2 Neutral that connects to the original ( common buss) to the ATS isolated buss. The inspector writes, without siting any specific code section, He just says Article 250. He States-1) " Generator configuration has new transfer switch as first point of disconnect. Main bond needs to be achieved ." A.-new "Main"and all grounds/neutrals isolated @ all load side sub panels. and 2.) " Relocate GEC termination to transfer switch.
So upon this statement the inspector is now classifying the 4 space buss in the original main panel as a sub-panel. The complication lies n the main ground buss there being commonly bonded to the enclosure and the utility neutral lands there. I am asking if anyone has a "exception" code or can give me any arguments that I could bring forth to the Solano County Building Department in My defense. We are contemplating changing the Service rated ATS out with a non service rated unit that has no main and the two original breakers will be the point of disconnect. This will cost me and the Client won't have as good of a system, but I don't know of any alternatives because to replace the main bonding would cost me about $1500.00 I have a series of pictures that I can send to any emails that reply by PM.
 
Welcome to the forum! Just a little bit of direction here before we get to your questions. Your post is extremely hard to read. You need to break up the post into paragraphs, with line spacing, so all the lines/words don't all run together.

IMO, I don't think you can have a meter/main and feed an ATS and make the ATS the first means of disconnect with OCP. I think the inspector is incorrect. You can't legally change the meter/main by removing the MBJ that is factory installed. When I say legally, I'm referring to the listing. So the meter/main should remain the "main" and the ATS would be treated as a subpanel.
 
You can feed the ATS with conductors from the 100a breaker, then feed the sub-panel, but you're not supposed to interrupt the factory wires between the meter and the main lugs.
 
Meter mains are listed as suitable for use ONLY as service equipment, not SUSE as the neutral/ground bond is permanent and not removable. This alone will prevent this from being a compliant install let alone the issue of modifying the equipment.
 
In other words, with the ATS as the service disconnect, there's no compliant way to convert the meter/main's breaker compartment into a sub-panel.
 
I agree with the others. If the 200 amp breaker in the meter main is still the Service Disconnect and, as best I can read, it is, then your ATS becomes a sub-panel and the Neutrals & Grounds would be separated in it.
As mentioned, you are altering a factory panel which would be a violation. I have seen similar arrangements that the AHJ allowed.
 
augie47 said:
I agree with the others. If the 200 amp breaker in the meter main is still the Service Disconnect and, as best I can read, it is, then your ATS becomes a sub-panel and the Neutrals & Grounds would be separated in it.
As mentioned, you are altering a factory panel which would be a violation. I have seen similar arrangements that the AHJ allowed.
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As best I could make out in the OP, there was no main breaker in the meter/main. It was a 200A rated main but only had two breakers for feeders. It's still the main and would qualify since it didn't have more than six breakers or "throws of the hand". This could have thrown the inspector off but he should know it had to be the main since it was a meter/main.
 
Little Bill said:
As best I could make out in the OP, there was no main breaker in the meter/main. It was a 200A rated main but only had two breakers for feeders. It's still the main and would qualify since it didn't have more than six breakers or "throws of the hand". This could have thrown the inspector off but he should know it had to be the main since it was a meter/main.
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Yes, that's my take of the OP, and only part of the problem. At the risk of being repetitive:

The inspector is missing the fact that (correctly) bonding the neutral and ground in the ATS would mean everything it in turn feeds needs to not have the neutral and ground bonded. Thus, it can not return to the meter/main's permanently-bonded neutral.

One main breaker or two, there's no compliant way to feed the entire load (100a and 60a breakers) from the ATS, because doing so would make the (one or) two breakers sub-panel breakers, require separating the permanently-bonded neutral from ground.
 
Little Bill said:
As best I could make out in the OP, there was no main breaker in the meter/main. It was a 200A rated main but only had two breakers for feeders. It's still the main and would qualify since it didn't have more than six breakers or "throws of the hand". This could have thrown the inspector off but he should know it had to be the main since it was a meter/main.
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I said " There was no main. in the original configuration. Only provisions for two double pole breakers. One breaker is The sub panel ( with all of the house circuit breakers)) The other breaker feeds the 5 ton AC. Since the client wants the AC to work on Generator as well,, We installed the Kohler RXT-JFNC-200ASE Automatic Transfer Switch, which has a service rated 200A breaker. The electrical flow goes from the meter- to the ATS main ( Utility Lugs) then the (Load goes back to the main lugs of the 4 space buss, thats feeds the original breakers, So the Inspector says " The ATS is the first point of disconnect. "
 
Bonham Electric said:
I said " There was no main. in the original configuration. Only provisions for two double pole breakers. One breaker is The sub panel ( with all of the house circuit breakers)) The other breaker feeds the 5 ton AC. Since the client wants the AC to work on Generator as well,, We installed the Kohler RXT-JFNC-200ASE Automatic Transfer Switch, which has a service rated 200A breaker. The electrical flow goes from the meter- to the ATS main ( Utility Lugs) then the (Load goes back to the main lugs of the 4 space buss, thats feeds the original breakers, So the Inspector says " The ATS is the first point of disconnect. "
Click to expand...
You're lucky he approved it.

Between us, you still have the bonded neutral in what is now a sub-panel.

Because of that, the bond should not also be made in the ATS.
 
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