230.71(A)

[hhsting]

Six disconnect rule didn't disappear, they just can't be in same enclosure/section anymore. What you described would still be allowed.

Ok but post #15 second draft report 230.71(B)(3)(4) says switchboard is allowed to have six service disconnect so as long as they have separate compartments or vertical sections?

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[jaggedben]

Just hurry up and get that installed before the 2020 code is adopted. Multiple service disconnects in a common enclosure will not be permitted in the 2020 code.

This is the worst news I've heard, like, ever.

 

[electrofelon]

This is the worst news I've heard, like, ever.

Yup. Some pretty clueless people must have been involved with that one. I read one of the proposals and the author said something like MLO service panelboards are "no longer relevant". Apparently that person has never designed and priced a mid to large sized service, doesn't understand series ratings, and hasn't done any solar.

 

[Cow]

We buy a lot of Siemens swbd's every year using the six disconnect rule. I'm going to have to ask our vendor how Siemens will be handling this.

I really hope they can do compartments of some sort to comply. Putting each breaker in it's own vertical section with barriers seems like it would create such a large footprint it would be ridiculous.

 

[tom baker]

I like this discussion, moderator vs moderator!

 

[LarryFine]

I like this discussion, moderator vs moderator!

Like the kids who instigates arguments between their parents.

 

[kwired]

Ok but post #15 second draft report 230.71(B)(3)(4) says switchboard is allowed to have six service disconnect so as long as they have separate compartments or vertical sections?

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This is mostly going to eliminate using a MLO panelboard and installing two to six breakers as your service disconnecting means, or even a seventh or eighth in certain allowed situations.

Your typical "Loadcenters" aren't normally rated to be used that way anyhow. Most all have instructions they need to have a main breaker if used as service equipment. Some commercial/industrial panelboards can be used in this way though.

I don't deal with many switchboards, but those are kind of customized for the application anyway - if you want six service disconnects in the switchboard, they will build it to comply with any rules changes if necessary.

Add, could even be asked when bidding/ordering which edition of NEC it needs to comply with.

 

[jaggedben]

...
Your typical "Loadcenters" aren't normally rated to be used that way anyhow. Most all have instructions they need to have a main breaker if used as service equipment. Some commercial/industrial panelboards can be used in this way though.
...

But there are a ton of existing meter/main combo service equipment enclosures in my area that are MLO. Just a ton. Hundreds of thousands if not a million in our service area. Like a 3rd of the service panels in suburban areas, I'd say. Especially subdivisions dating from, oh, about 1970 to 2000.

Here's a fairly typical example that we're dealing with presently:





(Note the part of the label that specifies the six-handle limit.)

So in a couple years this panel will be bafflingly no longer compliant.

The question is, will we still be allowed to do what we're doing on this job, which is to relocate that 40A circuit to a sub we're installing on the opposite side of the wall, into which we're also inserting our solar breaker? Will the AHJ be reasonable and say that the whole MSP is grandfathered? Or will we have to tell the customer that they need to increase the cost of the project by 10-50% to replace this recessed meter/main, and it's for a really stupid reason that wouldn't have existed in any of the decades since their house was built?

 

[jaggedben]

I also fear it will throw into question solar supply side connections. It's also common to find these meter/mains with two space unused. So, easy solar connection under 705.12(A). The expanded 705.11 in the 2020 code ought to have made these even easier. But now I can see AHJ's saying 'no, you can't add another breaker to this enclosure. You could do a supply side connection but only if you go to a separate enclosure'. Which when talking about meter/mains is exactly the same as saying 'you need to replace the !#@$ service equipment'. So we just went from no change orders for the customer to maybe they don't want to do the project anymore.
:rant::rant::rant:

 

[electrofelon]

I also fear it will throw into question solar supply side connections. It's also common to find these meter/mains with two space unused. So, easy solar connection under 705.12(A). The expanded 705.11 in the 2020 code ought to have made these even easier. But now I can see AHJ's saying 'no, you can't add another breaker to this enclosure. You could do a supply side connection but only if you go to a separate enclosure'. Which when talking about meter/mains is exactly the same as saying 'you need to replace the !#@$ service equipment'. So we just went from no change orders for the customer to maybe they don't want to do the project anymore.
:rant::rant::rant:

If it's too late for NEC 2020, I would say try to talk to your state code people who are in charge if adopting/amending the NEC. This is what I plan to do in WA. Of course, unfortunately, most states seem to blindly adopt the latest NEC with all it's unsubstantiated changes and corporate product pushing, but maybe you can get through to someone reasonable.

 

[kwired]

Do we know if there is any exceptions being added to deal with things that were compliant when first installed? That would help some with variations on local level on how to deal with existing, unless the intent of the CMP is to eliminate these altogether.

There are still a lot of split bus panels still out there.

Other than to better coordinate with worker safety rules (harder to have a completely de-energized panelboard to work on, yet not impossible) I don't see a great reason for this rule, not sure why the old split bus was even eliminated, other than the ignorant abusing rules they didn't know about.

 

[charlie b]

If it's too late for NEC 2020, I would say try to talk to your state code people who are in charge if adopting/amending the NEC. This is what I plan to do in WA.

Last cycle, I was chair of the committee that developed the Seattle amendments to the NEC. I expect to take on the same role this cycle. I will make sure this issue is carefully considered.

I am not sure when the state of Washington with take up the 2020 NEC. Nor could I find out (in the few minutes I was able to spend this morning) who the committee members are.

 

[electrofelon]

Last cycle, I was chair of the committee that developed the Seattle amendments to the NEC. I expect to take on the same role this cycle. I will make sure this issue is carefully considered.

I am not sure when the state of Washington with take up the 2020 NEC. Nor could I find out (in the few minutes I was able to spend this morning) who the committee members are.

Thanks Charlie. Ill be in touch, and can work up a formal letter to submit when the time comes.

 

[tortuga]

What is the substantiation for this 2020 code change? Were there problems with firefighters disconnecting power or something?
This seems like nonsense without some context.
I figured we would adopt international light blue neutrals before something like this happened in 2020 ?

 

[don_resqcapt19]

What is the substantiation for this 2020 code change? Were there problems with firefighters disconnecting power or something?
This seems like nonsense without some context.
I figured we would adopt international light blue neutrals before something like this happened in 2020 ?

It is driven by 70E in an attempt to limit incident energy and exposure to line side energized parts.

 

[xformer]

But there are a ton of existing meter/main combo service equipment enclosures in my area that are MLO. Just a ton. Hundreds of thousands if not a million in our service area. Like a 3rd of the service panels in suburban areas, I'd say. Especially subdivisions dating from, oh, about 1970 to 2000.

Here's a fairly typical example that we're dealing with presently:

View attachment 22855
View attachment 22856


(Note the part of the label that specifies the six-handle limit.)

So in a couple years this panel will be bafflingly no longer compliant.

The question is, will we still be allowed to do what we're doing on this job, which is to relocate that 40A circuit to a sub we're installing on the opposite side of the wall, into which we're also inserting our solar breaker? Will the AHJ be reasonable and say that the whole MSP is grandfathered? Or will we have to tell the customer that they need to increase the cost of the project by 10-50% to replace this recessed meter/main, and it's for a really stupid reason that wouldn't have existed in any of the decades since their house was built?

IMHO, The Code only applies to newly installed equipment not existing installations.

 

[hhsting]

Why must only new equipment comply? Post #25 if its to limit incident energy I would imagine existing equipment to must comply as well due to safety reasons. Something needs to be address in 2020 regarding existing equipment not to be left to individual AHJ. I could forsee lots of fights and headache with contractors why we have to replace existing if code does not address what to do existing.

 

[jaggedben]

IMHO, The Code only applies to newly installed equipment not existing installations.

1) That's just your opinion. If my company had the money back from every time an inspector had a different opinion than me, we could probably pay someone's yearly salary.

2) I'm talking about making changes to service equipment installations that run afoul of this new language. My part of the installation isn't 'existing.'

 

[kwired]

It is driven by 70E in an attempt to limit incident energy and exposure to line side energized parts.

That was my suspicion all along, They now require line barriers on main terminals - might not completely be compliant to 70E for limiting exposure, but is a step in that direction anyway. Now if you have a main lug only and bus that is always energized - it is more difficult to get that into as limiting of exposure condition as it would be with a single main breaker.

IMHO, The Code only applies to newly installed equipment not existing installations.

Most places recognize things that were compliant at the time they were installed. The question becomes can you add to this panel that once was compliant but now is not? If NEC does not specifically put in conditions for this, whether it be in main language or as exceptions, I can see there being a mixture of ways of dealing with the existing by AHJ's.

 

[inspector141]

Why must only new equipment comply? Post #25 if its to limit incident energy I would imagine existing equipment to must comply as well due to safety reasons. Something needs to be address in 2020 regarding existing equipment not to be left to individual AHJ. I could forsee lots of fights and headache with contractors why we have to replace existing if code does not address what to do existing.

The NEC is correlating and attempting to harmonize with 70E. In 70E, it is allowed to work on or around energized parts if it is "infeasible" to de-energize. Many would consider a MLO service panel to fall under this allowance due to the fact that the only way to de-energize is to have the utility company shut the entire building down. It sounds like 70E wants to eliminate this type of new installation due to shock hazards and high incident energy levels.

Existing installations are just that, existing.