proper location of bonding of service

[doncloutierelectric.com]

i installed a 200 amp meter can with a non fused service rated double throw switch that than feeds a 200 main breaker panel. i want to make sure i know where to run the gec to and where i bond. i think i bond at breaker panel and than run a ground wire from main panel back gen. switch. i have pvc between all gear.

 

[texie]

i installed a 200 amp meter can with a non fused service rated double throw switch that than feeds a 200 main breaker panel. i want to make sure i know where to run the gec to and where i bond. i think i bond at breaker panel and than run a ground wire from main panel back gen. switch. i have pvc between all gear.

Your GEC should go to the main breaker panel and the bonding screw installed. You can save a bonding jumper by simply installing the neutral bond screw in the DT switch as you are allowed to bond any metallic enclosures on the line side of the service disconnect to the neutral conductor. The meter can you can do the same (likely already factory bonded).

 

[electrofelon]

Your GEC should go to the main breaker panel and the bonding screw installed. You can save a bonding jumper by simply installing the neutral bond screw in the DT switch as you are allowed to bond any metallic enclosures on the line side of the service disconnect to the neutral conductor. The meter can you can do the same (likely already factory bonded).

Texie, I disagree. the DT switch is the service disconnect so the GEC cannot land past that nor can there be a bond after it.

OP your OCPD needs to be "immediately adjacent" to the DT switch, is it?

 

[don cloutier]

yes they are grouped together

 

[augie47]

As far as the GEC, When in doubt, the Code................
250.24(A)(1) General. The grounding electrode conductor connection shall be made at any accessible point from the load end of the overhead service conductors, service drop, underground serv ice conductors, or service lateral to, including the terminal or bus to which the grounded service conductor is connected at the service disconnecting means.

 

[Cow]

GEC goes to the transfer switch(service disconnect) where your main bonding jumper is installed. Neutrals and grounds are kept separate after this point.

 

[roger]

Typically I run the GEC to the meter enclosure. The main bonding jumper is in the service gear.

I realize some clueless POCO's don't allow this.

Roger

 

[chrismarcellino]

Cow's response is the ideal way to do it and the only option before 2020 if you had to have an outdoor disconnect, most folks expect the service disconnect to be at the outdoor disconnect. It also has the fringe benefit of keeping the "main" panel as a feeder which provides simpler options for future solar/battery/generator load separation as your EGCs are already separated. It also allows the GECs from rods to stay outside (but out of the meter), which is nice in some circumstances.

However, in 2020, you have another option as this was added to 230.82 if you really wish to keep the service disconnect indoors (assuming that it is near the point of entrance ala 230.70(A)(1):

230.82 Equipment Connected to the Supply Side of Service Disconnect. Only the following equipment shall be permitted to be connected to the supply side of the service disconnecting means:
...
(10) Emergency disconnects in accordance with 230.85, if all metal housings and service enclosures are grounded in accordance with Part VII and bonded in accordance with Part V of Article 250.

If this is done, the new 230.85(3) stipulates that the outdoor disconnect be labeled EMERGENCY DISCONNECT, NOT SERVICE EQUIPMENT, as opposed to without the NOT in this case. The short circuit rating must meet the usual requirements and the neutral must also be bonded to the case and metal conduit in the usual fashions. The disconnect must be marked as permissible as service equipment by the mfgr. 250.130 is unchanged and requires the EGCs be bonded to the neutral in the service disconnect (indoor panel) in this case.

I assume this provision exists to make service upgrades easier, as you wouldn't have to separate neutrals from EGCs to add an outdoor disconnect, and can keep the grounded connectors indoors at this panel.

I don't really see any advantage in a not making the outdoor disconnect the service disconnection in a new service unless you want to use a MLO for cost reasons and your switch is an OCPD (which most are),

Would love to hear any thoughts on this or corrections on my understanding on this new code. Haven't actually seen this done.

 

[doncloutier]

Cow's response is the ideal way to do it and the only option before 2020 if you had to have an outdoor disconnect, most folks expect the service disconnect to be at the outdoor disconnect. It also has the fringe benefit of keeping the "main" panel as a feeder which provides simpler options for future solar/battery/generator load separation as your EGCs are already separated. It also allows the GECs from rods to stay outside (but out of the meter), which is nice in some circumstances.

However, in 2020, you have another option as this was added to 230.82 if you really wish to keep the service disconnect indoors (assuming that it is near the point of entrance ala 230.70(A)(1):

230.82 Equipment Connected to the Supply Side of Service Disconnect. Only the following equipment shall be permitted to be connected to the supply side of the service disconnecting means:
...
(10) Emergency disconnects in accordance with 230.85, if all metal housings and service enclosures are grounded in accordance with Part VII and bonded in accordance with Part V of Article 250.

If this is done, the new 230.85(3) stipulates that the outdoor disconnect be labeled EMERGENCY DISCONNECT, NOT SERVICE EQUIPMENT, as opposed to without the NOT in this case. The short circuit rating must meet the usual requirements and the neutral must also be bonded to the case and metal conduit in the usual fashions. The disconnect must be marked as permissible as service equipment by the mfgr. 250.130 is unchanged and requires the EGCs be bonded to the neutral in the service disconnect (indoor panel) in this case.

I assume this provision exists to make service upgrades easier, as you wouldn't have to separate neutrals from EGCs to add an outdoor disconnect, and can keep the grounded connectors indoors at this panel.

I don't really see any advantage in a not making the outdoor disconnect the service disconnection in a new service unless you want to use a MLO for cost reasons and your switch is an OCPD (which most are),

Would love to hear any thoughts on this or corrections on my understanding on this new code. Haven't actually seen this done.

 

[doncloutier]

THANK-YOU FOR YOUR IDEAS. MY MAIN CONCERN WAS THAT THE GEN. SWITCH WAS UNFUSED AND THAT WOULD THAN HAVE ME BOND AT THE BREAKER PANEL. I DO NOW BELIEVE THAT ITS RIGHT TO BOND AT THE FIRST DISCONNECT WHICH WOULD BE THE GS AND THAN 4 WIRE TO MAIN PANEL NO POWER COMPANYS WILL LET US BRING GEC IN METER CAN THANKS

 

[texie]

THANK-YOU FOR YOUR IDEAS. MY MAIN CONCERN WAS THAT THE GEN. SWITCH WAS UNFUSED AND THAT WOULD THAN HAVE ME BOND AT THE BREAKER PANEL. I DO NOW BELIEVE THAT ITS RIGHT TO BOND AT THE FIRST DISCONNECT WHICH WOULD BE THE GS AND THAN 4 WIRE TO MAIN PANEL NO POWER COMPANYS WILL LET US BRING GEC IN METER CAN THANKS

In my post I should not have implied that the GEC had to go to the main breaker-it could attach at a number of points as augie47 pointed out. I do not agree that the unfused manual transfer switch is the service disconnect. It just happens to be a metallic item ahead of the main disconnect that needs bonding per 250.92. The way you are suggesting to run 4 wires implies an EGC is going from the transfer switch to the main disconnect. You can't have an EGC upstream of the service OCPD.

 

[electrofelon]

I do not agree that the unfused manual transfer switch is the service disconnect. It just happens to be a metallic item ahead of the main disconnect that needs bonding per 250.92.

And I forgot about the new outside safety disconnect requirement that may allow for this to NOT be called the service disconnect. But if we are talking prior to 2020 NEC, I dont see how this could not be called the service disconnect.

The way you are suggesting to run 4 wires implies an EGC is going from the transfer switch to the main disconnect. You can't have an EGC upstream of the service OCPD.

Its a bit odd as the definitions of feeder and the various types of service conductors use the word "service equipment" and not specifically "service disconnect", however 250.24(A)(5) and 250.142 specifically say no grounded conductor connections past the service disconnecting means. IT appears that with a seperate service disconnect and then an OCPD after it, it would be 4 wire, but it would be an SSBJ not an EGC.

 

[roger]

Cow's response is the ideal way to do it and the only option before 2020 if you had to have an outdoor disconnect, most folks expect the service disconnect to be at the outdoor disconnect.

Please explain why you think that was the only option.

Roger

 

[Cow]

I do not agree that the unfused manual transfer switch is the service disconnect.

A service rated non fused transfer switch qualifies as a service disconnect despite not having an integral OCPD.

 

[Dennis Alwon]

While the Non - fused disconnect can be part of the service that does not mean the service ends there. The service must include overcurrent protective device.

230.91 Location. The service overcurrent device shall be an
integral part of the service disconnecting means or shall be
located immediately adjacent thereto. Where fuses are used as
the service overcurrent device, the disconnecting means shall
be located ahead of the supply side of the fuses.

 

[chrismarcellino]

Please explain why you think that was the only option.

Roger

Since you couldn't have a standalone disconnect that was not integral to a standby power switch (e.g. 230.82(5)) or one of the another exceptions of 230.82 that was not the service disconnect prior to 2020, and since his switch is non-fused, he must have an OCPD adjacent outside (230.91). In that case, the service disconnect must be one of these two items outside pre-2020. Right? Or am I missing something?

The only difference in 2020 is that the standalone OCPD may be before the service disconnect 230.82 now, so the service disconnect can be inside if it is near the entry point of the conductors into the structure?

(If the switch is not rated as a service disconnect, then the ECG can't land there. If the ECG is brought into the switch, then the OCPD must be adjacent outside. Otherwise just needs to be near the entry point inside the structure?) Right? Thanks for clarifying/correcting.

 

[roger]

I think you may be confusing the EGC with the GEC? The GEC can bond to the grounded conductor anywhere before and up to the service equipment.

Roger

 

[chrismarcellino]

I think you may be confusing the EGC with the GEC? The GEC can bond to the grounded conductor anywhere before and up to the service equipment.

Roger

Thanks. I guess here is my question (which is suppose is a bit off topic):
- have a transfer switch adjacent to meter
- transfer switch is unfused, so have an OCPD outside immediately adjacent per 230.91
- conduit PVC sch 40 between equipment
- 2017 NEC, so standalone disconnect not yet allowed (or required) prior to 2020 as 230.82(10) not yet in effect
- service equipment definition (art. 100) in this state just constitutes the actual disconnect hardware in the service rated MTS (not the OCPD)
- therefore, the standalone OCPD must be the service disconnect since it is not integral with the switch so not permitted by any part of 230.82? Right?
- hence an EGC must run from the OCPD to the main feeder panel, and the main feeder panel neutral bus must not be bonded

Where am I going wrong? (in NEC 2017, which will soon not matter here, and I think everyone agrees doncloutier's plan is good and his service rated switch can be the disconnect)

 

[doncloutier]

i’m in wis. under 17 code. we know gs is not a ocpd. non fused but just a disconnect. 4 wire would only be between them. i

 

[doncloutier]

seems we’re on the same page we all know that bonding and grounding in either gs or main disconnect will clear a fault right? all you guys are great thanks.