glock19
Just finishing up an install on a 22kw model 7043. The generator installation guide states that there is no requirement for neutral to be bonded to ground at the generator if it is being used as a backup source to utility supplied service.

What about the bonding jumper at the transfer switch? It is sent from the factory with this jumper connected between the neutral bus bar and the ground bus bar. I assume it should be installed that way?

If so, is there any need to run a separate ground between the utility meter and the transfer switch? Seems redundant since the neutral and the ground are connected together in the meter box.
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Cobranut
I believe code requires neutral and ground to be bonded at ONE POINT only.
Normally, that is at the service disconnect enclosure.
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Ziller Tech
glock19;51166 wrote:
Just finishing up an install on a 22kw model 7043. The generator installation guide states that there is no requirement for neutral to be bonded to ground at the generator if it is being used as a backup source to utility supplied service.

What about the bonding jumper at the transfer switch? It is sent from the factory with this jumper connected between the neutral bus bar and the ground bus bar. I assume it should be installed that way?

If so, is there any need to run a separate ground between the utility meter and the transfer switch? Seems redundant since the neutral and the ground are connected together in the meter box.


That is a service rated transfer switch you are talking about so that bond is normal since the breaker is now the first means of disconnect. The grounding electrodes should also come to that new switch and any grounds and neutrals after the switch are required to be separated (since everything else is now a sub-panel of the switch), including the bonding jumper in the old main panel.

I would [I]HIGHLY[/I] recommend consulting with a licensed electrician to make sure that the installation meets all of the local code requirements for your area. :)
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BMerrill
glock19;51166 wrote:
Just finishing up an install on a 22kw model 7043.
If so, is there any need to run a separate ground between the utility meter and the transfer switch? Seems redundant since the [B]neutral and the ground are connected together in the meter box[/B].


Interesting question. As Chris stated above, you should consult with the AHJ, a licensed electrician, and the utility company.

Why did I add the utility company?

Some utility companies require the ground to grounded conductor (neutral) connection to be made in the meter base. This maybe your case since you stated the [U]neutral and the ground are connected together in the meter base[/U]. This is not typical and is usually done in the main service equipment disconnect panel. It is very crucial to make sure the ground to grounded conductor (neutral) connection is made at one location and one location only.


Have you laid eyes on the ground to neutral bonding in the meter base?

Interesting article on bonding [url]http://www.adamselectric.coop/wp-content/uploads/2015/02/Grounding-Bonding.pdf[/url]
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ceb58
BMerrill;51169 wrote:
Interesting question. As Chris stated above, you should consult with the AHJ, a licensed electrician, and the utility company.

Why did I add the utility company?

Some utility companies require the ground to grounded conductor (neutral) connection to be made in the meter base. This maybe your case since you stated the [U]neutral and the ground are connected together in the meter base[/U]. This is not typical and is usually done in the main service equipment disconnect panel. It is very crucial to make sure the ground to grounded conductor (neutral) connection is made at one location and one location only.


Have you laid eyes on the ground to neutral bonding in the meter base?

Interesting article on bonding [url]http://www.adamselectric.coop/wp-content/uploads/2015/02/Grounding-Bonding.pdf[/url]


The neutral ground connection must be made AT or BEFORE the first disconnecting means. I have never ran across a utility that required the bond in the meter but they did not discourage it. There are some utilities in other states that forbid the bond in the meter base. Their reasoning is if there were a problem the seal would be cut and meter removed. Something they don't want done. Some utility's supply the meter base and they don't want anyone messing with their equipment.
I have seen the grounding electrode conductor ran up the wall and bonded to the neutral at the weather head. That was done when copper was cheap
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glock19
BMerrill;51169 wrote:



Have you laid eyes on the ground to neutral bonding in the meter base?

Interesting article on bonding [url]http://www.adamselectric.coop/wp-content/uploads/2015/02/Grounding-Bonding.pdf[/url]


Yes...... the configuration is that the utility company's neutral terminates to a terminal lug in the meter base. From this same terminal lug the neutral wire to the breaker panel (now to the transfer switch) originates. The wire from the ground rod adjacent to the meter base is also physically connected to this same neutral terminal lug.

So, with the above information, back to my original question: if the bonding jumper in the transfer switch is to be left intact between the neutral bus and the ground bus, do I need to run a separate ground lead between the meter base and the transfer switch ground bus?

Thanks for the link on bonding. Very good.
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nrp3
Some utilities want a ground in the meter base, some do not. Here, they want one, so the ground rods will end up in the meter base. The water pipe ground I will bring to the service whether its the transfer switch or the panel if there is no transfer switch or disconnect before the panel.
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ceb58
glock19;51177 wrote:
Yes...... the configuration is that the utility company's neutral terminates to a terminal lug in the meter base. From this same terminal lug the neutral wire to the breaker panel (now to the transfer switch) originates. The wire from the ground rod adjacent to the meter base is also physically connected to this same neutral terminal lug.

So, with the above information, back to my original question: if the bonding jumper in the transfer switch is to be left intact between the neutral bus and the ground bus, do I need to run a separate ground lead between the meter base and the transfer switch ground bus?

Thanks for the link on bonding. Very good.


No, only the neutral needs to be ran from the meter base to the ats and leave the bonding jumper. It is from the ats to the generator and the distribution panel that you run 4 wires. You will now need to separate the ground- neutral bond in the distribution panel. The equipment grounding conductors now must be separated from the neutrals and isolated.
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Ziller Tech
glock19;51177 wrote:
Yes...... the configuration is that the utility company's neutral terminates to a terminal lug in the meter base. From this same terminal lug the neutral wire to the breaker panel (now to the transfer switch) originates. The wire from the ground rod adjacent to the meter base is also physically connected to this same neutral terminal lug.

So, with the above information, back to my original question: if the bonding jumper in the transfer switch is to be left intact between the neutral bus and the ground bus, do I need to run a separate ground lead between the meter base and the transfer switch ground bus?

Thanks for the link on bonding. Very good.


If that's the case, then I would assume that the original panel also had a 4-wire feeder and not the normal 3-wire?
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BMerrill
If you only have a 3 wire feed from the meter to the main panel, then chase down the ground from the main panel and see where it goes.
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Brian Baughman
Please note that a single meter socket enclosure is not considered to be service equipment and is not listed as such, unless the meter socket enclosure contains a listed service disconnecting means, typically one to six circuit breakers, but it could be fuses. The neutral is typically bonded to the meter enclosure in every meter socket approved for installation in the USA.

From the meter to the single phase service rated ATS, a set of service entrance conductors are required to be installed. (3 wire feeder) The ATS is listed as suitable for use as service equipment and has to be installed as such, as required by 230.82(5). The grounding electrode conductors have to be terminated in the ATS. From the ATS to any downstream panelboard, a 4 wire feeder is required, and all equipment grounding conductors and neutral conductors have to be isolated from each other.
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ceb58
Brian Baughman;51199 wrote:
Please note that a single meter socket enclosure is not considered to be service equipment and is not listed as such, unless the meter socket enclosure contains a listed service disconnecting means, typically one to six circuit breakers, but it could be fuses. The neutral is typically bonded to the meter enclosure in every meter socket approved for installation in the USA.

From the meter to the single phase service rated ATS, a set of service entrance conductors are required to be installed. (3 wire feeder) The ATS is listed as suitable for use as service equipment and has to be installed as such, as required by 230.82(5). The grounding electrode conductors have to be terminated in the ATS. From the ATS to any downstream panelboard, a 4 wire feeder is required, and all equipment grounding conductors and neutral conductors have to be isolated from each other.


Disagree with the statement about the grounding electrode conductor needing to be terminated in the ATS. His grounding electrode conductor is bonded with the neutral in the meter base. It can stay there. They must be bonded at or BEFORE the first disconnecting means. 250.24 (A)(1)
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Ziller Tech
ceb58;51251 wrote:
Disagree with the statement about the grounding electrode conductor needing to be terminated in the ATS. His grounding electrode conductor is bonded with the neutral in the meter base. It can stay there. They must be bonded at or BEFORE the first disconnecting means. 250.24 (A)(1)


So like my original question, that would mean that you'd need 4-wire from the meter to any downstream panel or disconnect which would be wired like a sub-panel. The meter socket being used as the point of bonding the electrodes isn't a thing here in MI. All of our meter enclosures have the neutral bonded to the can, however usually it's plastic pipe and SE cable feeding in and out so it's really just to open a fuse at the pole should an ungrounded (hot) come loose I'd assume...
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ceb58
Chris Flagg;51259 wrote:
So like my original question, that would mean that you'd need 4-wire from the meter to any downstream panel or disconnect which would be wired like a sub-panel. The meter socket being used as the point of bonding the electrodes isn't a thing here in MI. All of our meter enclosures have the neutral bonded to the can, however usually it's plastic pipe and SE cable feeding in and out so it's really just to open a fuse at the pole should an ungrounded (hot) come loose I'd assume...


No, in this case there would be 3 wire ran to the ATS because that is where the main disconnect/overcurrent devise is. In the ATS is where the neutral will bond to the enclose via a bonding jumper from the buss bar. Now from the ATS there must be 4 wires ( 2- ungrounded ) ( 1- grounded ) and ( 1- equipment grounding ) conductor ran to the distribution panel which now is a sub-panel and to the generator. It is in the sub panel and generator that the grounded ( neutral ) must be isolated from the equipment grounding conductors.
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glock19
As the OP I want to thank everyone who has posted. I've learned a lot and appreciate all the advice. Lots of good info on this forum.
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Ziller Tech
ceb58;51267 wrote:
No, in this case there would be 3 wire ran to the ATS because that is where the main disconnect/overcurrent devise is. In the ATS is where the neutral will bond to the enclose via a bonding jumper from the buss bar. Now from the ATS there must be 4 wires ( 2- ungrounded ) ( 1- grounded ) and ( 1- equipment grounding ) conductor ran to the distribution panel which now is a sub-panel and to the generator. It is in the sub panel and generator that the grounded ( neutral ) must be isolated from the equipment grounding conductors.


So you're bonding neutral and ground in the meter, and then again in the transfer switch...? That doesn't seem right.
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Birken Vogt
Chris Flagg;51321 wrote:
So you're bonding neutral and ground in the meter, and then again in the transfer switch...? That doesn't seem right.


It is done all the time from what I know. Meter pan usually has neutral/ground bonded, 3 wires in, 3 wires out. Only when it hits the first main disconnect does it become a 4 wire service.

To be honest it does not bother me at all. Neutral is bonded to ground all kinds of places on the pole and such. And 3 wire circuits used to be the norm to outbuildings, ranges, dryers. As long as it is done correctly and solidly, there is no hazard.
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Brian Baughman
Chris Flagg;51321 wrote:
So you're bonding neutral and ground in the meter, and then again in the transfer switch...? That doesn't seem right.


Meter socket enclosures are permitted to be connected ahead of the service disconnect where the metal housings of the meter enclosure are bonded in accordance with Part V and grounded in accordance with Part VII of Article 250 in the NEC. In plain English, the neutral conductor in the meter socket enclosure has to be bonded to the enclosure (230.82). This connection is not considered to be part of the main bonding jumper for the service in the USA, as the meter enclosure is not considered to be service equipment unless the service disconnect is part of the equipment.

Canada in the 2018 CEC has different requirements.

Some utility providers require ground rods to be connected to the meter enclosure, and there are some cases where both the meter enclosure and service disconnecting means are connected to ground rods.
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Ziller Tech
Birken Vogt;51331 wrote:
It is done all the time from what I know. Meter pan usually has neutral/ground bonded, 3 wires in, 3 wires out. Only when it hits the first main disconnect does it become a 4 wire service.

To be honest it does not bother me at all. Neutral is bonded to ground all kinds of places on the pole and such. And 3 wire circuits used to be the norm to outbuildings, ranges, dryers. As long as it is done correctly and solidly, there is no hazard.


Hmm, well I trust that it's normal then. We don't have those type of services here in Michigan (that I'm aware of), so I haven't ever seen one. Just seems odd that you wouldn't bond everything as normal in the switch. We bring the ground rods and water bond direct to the switch and then everything past that point is considered a sub-panel and gets 4-wire.
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murphy
I have solar panels that connect before the service entrance. The main disconnect is outside of the house right after the meter That is where neutral and ground are bonded. That is where the ground rod is connected. The inspector opened up the main disconnect to verify that. 4 wire cable is used from that point on. The installer had a rough time separating the neutral and ground in my main panel since everything was connected to the neutral bar. He installed a ground bar and then got all of the grounds off of the neutral bar.
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nrp3
I'd like to say every meter socket I've worked with has been bonded to the neutral. Most newer ones have a ground lug in them. That being said, there are different standards for meter sockets across the country. Take a look at Milbanks catalogs. Not sure how much a standard single gang 200 amp meter socket varies though.
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ceb58
Chris Flagg;51321 wrote:
So you're bonding neutral and ground in the meter, and then again in the transfer switch...? That doesn't seem right.


Chris Flagg;51333 wrote:
Hmm, well I trust that it's normal then. We don't have those type of services here in Michigan (that I'm aware of), so I haven't ever seen one. Just seems odd that you wouldn't bond everything as normal in the switch. We bring the ground rods and water bond direct to the switch and then everything past that point is considered a sub-panel and gets 4-wire.


Chris lets back up and get the terminology correct. In this case the OP's GROUNDING ELECTRODE conductors are bonded to the neutral in the meter base. From there there is only 3 wires to the ATS. The neutral is on a buss bar that is BONDED to the ATS enclosure. No GROUNDING going on. It is from there that the neutrals and the EQUIPMENT GROUNDING conductors originate to the distribution panel and generator.
In this install the OPs POCO allows for bonding of the grounding electrode conductor to be done in the meter base. So why go to the trouble and expense of moving it to the ATS?
On the other hand if it were a situation where the grounding electrode conductor could not/ was not bonded in the meter but in the distribution panel and you were now installing a SE rated ATS then the grounding electrode conductor would need to be move to the ATS to be bonded with the neutral. This is where the first disconnecting/overcurrent devise would be now.
Just remember the grounding electrode conductor must be bonded to the neutral AT or BEFORE the first disconnecting/ overcurrent devise.
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Birken Vogt
Chris Flagg;51333 wrote:
Hmm, well I trust that it's normal then. We don't have those type of services here in Michigan (that I'm aware of), so I haven't ever seen one. Just seems odd that you wouldn't bond everything as normal in the switch. We bring the ground rods and water bond direct to the switch and then everything past that point is considered a sub-panel and gets 4-wire.


What kind of service do you usually see where you are? Meter and main in one panel?

Around here it is usually meter/main/sub breakers all in one panel. Sometimes branch circuit breakers also in the same panel. Makes for challenging installation.

In other areas of the country, or very old installations here, I have seen the separate small meter pan. Flat SEU or underground in, flat SEU out, sometimes several yards into the house until it hits the main disconnect. Kind of scary if you ask me, I like everything to be inside strong conduit that cannot be quickly disconnected by a flip of a breaker. And I don't like transfer switches where you have to work inside with hot parts like the SE rated ones are, but "don't like" and "won't use" are not the same thing.
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nrp3
The worst transfer switches to work on are the non service entrance rated ones in between the meter and service panel for a lot of reasons.
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Ziller Tech
Birken Vogt;51346 wrote:
What kind of service do you usually see where you are? Meter and main in one panel?

Around here it is usually meter/main/sub breakers all in one panel. Sometimes branch circuit breakers also in the same panel. Makes for challenging installation.

In other areas of the country, or very old installations here, I have seen the separate small meter pan. Flat SEU or underground in, flat SEU out, sometimes several yards into the house until it hits the main disconnect. Kind of scary if you ask me, I like everything to be inside strong conduit that cannot be quickly disconnected by a flip of a breaker. And I don't like transfer switches where you have to work inside with hot parts like the SE rated ones are, but "don't like" and "won't use" are not the same thing.


Services here are meter enclosure (no grounding electrodes tied in there) then usually SE cable to the main panel (inside the home) where the water bond and supplemental grounding electrodes (ground rods) are all tied into the panel's neutral bars where there is a bond screw that ties the panel to the neutral.

If we install a SE rated switch (main breaker) then we get 3 wire SE from meter to ATS, all grounding electrodes are removed from the existing panel and brought out to first means of disconnect (ATS) and then 4-wire back down to original panel where the bond screw is removed and neutrals and grounds are separated.

AGAIN, not saying any other way is wrong, that's just how we do things here and what the inspectors are looking for... I don't believe I've ever seen a ground rod or water bond tied into a meter can here...
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