2020- 230.71(B) & 225.30(B) - Effect on homes with 2 - 200 amp panels

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sw_ross

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I'm currently working my way through MH's change book and videos. They (Brian) talk about the effects of the new changes on the smaller operations that typically install a 320 meter/main with 2 - 200 amp breakers feeding 2 - 200 amps panels.

That practice will not be code compliant as 2020 gets adopted.

This is a typical installation for me.

I'm trying to mentally work my way through how to handle this change.
How would you do a code compliant installation where you need 2 - 200 amp panels?

My reference to 225.30(B) is when the meter/main is located away from the residence and I'll have 2 feeders (4-wire) going to the residence to feed the 2 panels.
 
sw_ross said:
My reference to 225.30(B) is when the meter/main is located away from the residence and I'll have 2 feeders (4-wire) going to the residence to feed the 2 panels.
Click to expand...

I don't have the 2020 NEC yet but has this particular installation ever been code complaint with more than one supply to the structure?
 
I see this all the time, and have done this in the past.
its one supply going into a 320A meter base, then a double lug at the load side with two sets going to (2) 200 amp panels.

i haven’t looked at the 2020 at all, but I’m wondering if it would be compliant to simply get the panels with 150A breakers?

is it a problem of the (2) 200 amp panels potentially over loading the 320A continuous rated meterbase?
 
Here is the rule

Part VI. Service Equipment — Disconnecting Means
230.70 General.
Means shall be provided to disconnect all ungrounded conductors in a building or other structure from the service conductors.
230.70(A) Location.
The service disconnecting means shall be instal⁠led in accordance with 230.70(A)(1), (A)(2), and (A)(3).
230.70(A)(1) Readily Accessible Location.
The service disconnecting means shall be installed at a readily accessible location either outside of a building or structure or inside nearest the point of entrance of the service conductors.
230.70(A)(2) Bathrooms.
Service disconnecting means shall not be installed in bathrooms.
230.70(A)(3) Remote Control.
Where a remote control device(s) is used to actuate the service disconnecting means, the service disconnecting means shall be located in accordance with 230.70(A)⁠(1).
230.70(B) Marking.
Each service disconnect shall be permanently marked to identify it as a service disconnect.
230.70(C) Suitable for Use.
Each service disconnecting means shall be suitable for the prevailing conditions. Service equipment installed in hazardous (classified) locations shall comply with the requirements of Articles 500 through 517.
230.71 Maximum Number of Disconnects.
Each service shall have only one disconnecting means unless the requirements of 230.71(B) are met.
230.71(A) General.
For the purpose of this section, disconnecting means installed as part of listed equipment and used solely for the following shall not be considered a service disconnecting means:
  1. (1)
    Power monitoring equipment
  2. (2)
    Surge-protective device(s)
  3. (3)
    Control circuit of the ground-fault protection system
  4. (4)
    Power-operable service disconnecting means

230.71(B) Two to Six Service Disconnecting Means.
Two to six service disconnects shall be permitted for each service permitted by 230.2 or for each set of service-entrance conductors permitted by 230.40, Exception No. 1, 3, 4, or 5. The two to six service disconnecting means shall be permitted to consist of a combination of any of the following:
  1. (1)
    Separate enclosures with a main service disconnecting means in each enclosure
  2. (2)
    Panelboards with a main service disconnecting means in each panelboard enclosure
  3. (3)
    Switchboard(s) where there is only one service disconnect in each separate vertical section where there are barriers separating each vertical section
  4. (4)
    Service disconnects in switchgear or metering centers where each disconnect is located in a separate compartment

Informational Note No. 1: Metering centers are addressed in UL 67, Standard for Panelboards.
Informational Note No. 2: Examples of separate enclosures with a main service disconnecting means in each enclosure include but are not limited to motor control centers, fused disconnects, circuit breaker enclosures, and transfer switches that are suitable for use as service equipment.
230.
Click to expand...
 
Here is 225(B)

225.30(B) Common Supply Equipment.
Where feeder conductors originate in the same panelboard, switchboard, or other distribution equipment, and each feeder terminates in a single disconnecting means, not more than six feeders shall be permitted. Where more than one feeder is installed in accordance with this section, all feeder disconnects supplying the building or structure shall be grouped in the same location, and the requirements of 225.33 shall not apply. Each disconnect shall be marked to indicate the load served.
Click to expand...
 
IF I am understanding correctly: What you describe has always been non compliant if the meter main is remote due to the two feeders then serving the structures. Seems we will not also have the issue of having two service disconnects in a single meter main, correct?
 
As I understand it, if you have more than one disco (2-6), the disco's have to be separate enclosures.

Could you have 2 - 200 amp disconnects (separate enclosures) on the outside of the dwelling feeding the 2 panels inside the structure (complying with 230.71(B)(1))?

Since these would be the "Service Disconnecting Means" I'm assuming the discos have to be OCPD's?
 
This brings up a question I recently thought of: whether meter centers that have 2-6 disconnects instead of a single main will be still allowed. It seems to me most I have seen will NOT meet 230.71(B)(4). Are manufacturers restructuring such equipment? In regards to the OP, I havent used one of those 2-200 meter mains. Are they in separate compartments?
 
its just two separate 200 amp panels, sometimes side by side, coming from a double,lug on the load side of the 320A meter base.
 
The 320 meter/main I was referring to is a Siemens product.
It comes with one 200 amp breaker and a provision for another to be installed (not provided).
The main breaker that comes with it feeds a bus in the enclosure that has feed-through lugs at the bottom and has 8 spaces to feed thing like the a/c condense, etc.
It's all one enclosure.
Since it has 2 service discos it would not comply with 2020 since the service discos have to be in separate enclosures, if I'm understanding the 2020 correctly.

The meter socket is located in the left half of the enclosure with a barrier wall between the meter and the discos.
 
sw_ross said:
I'm currently working my way through MH's change book and videos. They (Brian) talk about the effects of the new changes on the smaller operations that typically install a 320 meter/main with 2 - 200 amp breakers feeding 2 - 200 amps panels.

That practice will not be code compliant as 2020 gets adopted.

This is a typical installation for me.

I'm trying to mentally work my way through how to handle this change.
How would you do a code compliant installation where you need 2 - 200 amp panels?

My reference to 225.30(B) is when the meter/main is located away from the residence and I'll have 2 feeders (4-wire) going to the residence to feed the 2 panels.
Click to expand...
Some things in there I was not aware of that changed. Before 2020 if you used such meter with 2 mains and it wasn't located on the building you would have violated 225.30 most all instances as you were only permitted to have one feeder to a separate building/structure. Now it looks like you can have 2-6 feeders if they all originate from same switchboard, panelboard, or other distribution equipment.

I knew they no longer allowed a panelboard with main lugs and six mains, but never gave any thought if that would apply to a meter with 2 mains, need to look into that one more before I have an answer on that.
 
sw_ross said:
The 320 meter/main I was referring to is a Siemens product.
It comes with one 200 amp breaker and a provision for another to be installed (not provided).
The main breaker that comes with it feeds a bus in the enclosure that has feed-through lugs at the bottom and has 8 spaces to feed thing like the a/c condense, etc.
It's all one enclosure.
Since it has 2 service discos it would not comply with 2020 since the service discos have to be in separate enclosures, if I'm understanding the 2020 correctly.

The meter socket is located in the left half of the enclosure with a barrier wall between the meter and the discos.
Click to expand...
I expect that these types of meter mains will either go away or more likely be re-engineered so that each main is in a separate compartment.
This all stems from to move in the last 2 code cycles toward not having any line side terminals in service equipment without barriers.
 
kwired said:
Some things in there I was not aware of that changed. Before 2020 if you used such meter with 2 mains and it wasn't located on the building you would have violated 225.30 most all instances as you were only permitted to have one feeder to a separate building/structure. Now it looks like you can have 2-6 feeders if they all originate from same switchboard, panelboard, or other distribution equipment.

I knew they no longer allowed a panelboard with main lugs and six mains, but never gave any thought if that would apply to a meter with 2 mains, need to look into that one more before I have an answer on that.
Click to expand...
After further reading I don't believe the 320 amp meter base with two mains is no longer compliant as a service disconnecting means (2020 NEC) unless they would modify the design so the two mains are in separate compartments.
 
That's what the MH video was saying.

So if you want to do a 320 meter to a residence for 2 panels would you have a 320/400 amp rated meter socket that is then chase nippled to 2 - 200 amp service disconnects?
 
sw_ross said:
That's what the MH video was saying.

So if you want to do a 320 meter to a residence for 2 panels would you have a 320/400 amp rated meter socket that is then chase nippled to 2 - 200 amp service disconnects?
Click to expand...
Yes. The easy way is to put one on each side of the meter. But some POCOs prohibit putting one on each side of the meter can due to interfering with underground feeds.
 
kwired said:
Some things in there I was not aware of that changed. Before 2020 if you used such meter with 2 mains and it wasn't located on the building you would have violated 225.30 most all instances as you were only permitted to have one feeder to a separate building/structure. Now it looks like you can have 2-6 feeders if they all originate from same switchboard, panelboard, or other distribution equipment.

I knew they no longer allowed a panelboard with main lugs and six mains, but never gave any thought if that would apply to a meter with 2 mains, need to look into that one more before I have an answer on that.
Click to expand...
Quite frequently I see a 320A meter feeding two 200A discos (or feedthrough panels with 200A main breakers) out on a rack some distance from the house feeding a pair of MLO panels on the house. Are you saying that this isn't or won't be NEC compliant?
 
Now I’m confused..,well kinda always am..

this is what I’m talking about, but reading here I’m not sure this is what the rest of you are referring to.
 

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ggunn said:
Quite frequently I see a 320A meter feeding two 200A discos (or feedthrough panels with 200A main breakers) out on a rack some distance from the house feeding a pair of MLO panels on the house. Are you saying that this isn't or won't be NEC compliant?
Click to expand...
There are two things going on here: One is the separate enclosure requirement for service disconnects (although seems to be a bit more lax for meter assemblies, then being separate "compartments"). The second is the "only one feeder to supply a building" requirement, which as far as I know has no recently changed in the code.
 
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