Meter banks and NEC 110.26

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Hv&Lv

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Yea but meter and meter bank is totally different things
I’m not arguing that.

from the exception I posted in 17
The meter socket shall be required to follow the rules of this section.
 
Last edited:

Tainted

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New York
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I’m not arguing that.

from the exception I posted in 17
The meter socket shall be required to follow the rules of this section.
Ok i’m assuming a meter bank is considered multiple sockets? Therefore meter banks need to follow 110.26, i can understand why it needs to follow working space clearance, but I don’t understand if dedicated space clearance applies
 

don_resqcapt19

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Ok i’m assuming a meter bank is considered multiple sockets? Therefore meter banks need to follow 110.26, i can understand why it needs to follow working space clearance, but I don’t understand if dedicated space clearance applies
Do you have the brand and model number of the equipment you are talking about? The manufacturer specifications will tell you what it is.

Not sure it would be possible to have a meter/disconnect combo that would not be covered by 110.26(E), but maybe.
 

Tainted

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Do you have the brand and model number of the equipment you are talking about? The manufacturer specifications will tell you what it is.

Not sure it would be possible to have a meter/disconnect combo that would not be covered by 110.26(E), but maybe.
It's a con-ed approved meter stack, you will have to do a special eaton order to get it, you won't find the exact one on eaton's website but it looks exactly something like this:

https://www.eaton.com/us/en-us/skuPage.3MM612RC.html
 

don_resqcapt19

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It's a con-ed approved meter stack, you will have to do a special eaton order to get it, you won't find the exact one on eaton's website but it looks exactly something like this:

https://www.eaton.com/us/en-us/skuPage.3MM612RC.html
Those are listed to UL 67 so they are panelboards and 110.26(E) applies.

Note that those assemblies are not compliant with the requirements of the 2020 NEC.
 

Tainted

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Those are listed to UL 67 so they are panelboards and 110.26(E) applies.

Note that those assemblies are not compliant with the requirements of the 2020 NEC.
Hmmm interesting… well that sucks… and NYC doesn’t care about 2020 electrical code, they only care about their own electrical code (based on 2011)
 

Carultch

Senior Member
Location
Massachusetts
Hmmm interesting… well that sucks… and NYC doesn’t care about 2020 electrical code, they only care about their own electrical code

Working space requirements have been very consistent over the last 20 years, although there has been some fine-tuning to these rules to help clarify further detail in later editions. Examples being a provision that now justifies housekeeping pads (and support structures in general) to stick out another 6", and listed panic hardware being specified in conditions where "open under simple pressure in the direction of egress" had previously been specified. Another example being that in 2014, dedicated space requirements were extended to outdoor equipment, to clarify that they still apply.

The change that is new in 2020 that Don is referring to, is the requirement for service disconnects to be either be in separate enclosures, or in separate sections of the same enclosure, so that you can work on one at a time, without the others being exposed. This applies if the disconnects of this bank of meters is your up-to-6 service disconnects that are allowed. They now have to be partitioned from each other, so that it is possible to only open the dead front of one of them at a time. You no longer can use a standard MLO panel as a hot-bus panelboard of your 6 service disconnects, or a meter/main with multiple disconnects, where 2020 applies, unless it is built with the partitions

If by contrast, your tenant meter bank is load-side of a master service disconnect (as you would do if you had more than 6 tenant meters), the new rule in 2020 would still allow you to use such a bank of tenant meters as that product is currently designed. Those disconnects would no longer be the "service disconnects" that the new rule in 2020 governs, because it would still be possible to de-energize them from the master disconnect.
 

Tainted

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New York
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Engineer
Working space requirements have been very consistent over the last 20 years, although there has been some fine-tuning to these rules to help clarify further detail in later editions. Examples being a provision that now justifies housekeeping pads (and support structures in general) to stick out another 6", and listed panic hardware being specified in conditions where "open under simple pressure in the direction of egress" had previously been specified. Another example being that in 2014, dedicated space requirements were extended to outdoor equipment, to clarify that they still apply.

The change that is new in 2020 that Don is referring to, is the requirement for service disconnects to be either be in separate enclosures, or in separate sections of the same enclosure, so that you can work on one at a time, without the others being exposed. This applies if the disconnects of this bank of meters is your up-to-6 service disconnects that are allowed. They now have to be partitioned from each other, so that it is possible to only open the dead front of one of them at a time. You no longer can use a standard MLO panel as a hot-bus panelboard of your 6 service disconnects, or a meter/main with multiple disconnects, where 2020 applies, unless it is built with the partitions

If by contrast, your tenant meter bank is load-side of a master service disconnect (as you would do if you had more than 6 tenant meters), the new rule in 2020 would still allow you to use such a bank of tenant meters as that product is currently designed. Those disconnects would no longer be the "service disconnects" that the new rule in 2020 governs, because it would still be possible to de-energize them from the master disconnect.

just researched it. I don’t really have to worry about it though because I have distribution on the load side of service disconnect. The disconnects after the main service disconnect is feeding all the meter banks.

In practice I would always separate service disconnects anyway
 

don_resqcapt19

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Illinois
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retired electrician
.....

The change that is new in 2020 that Don is referring to, is the requirement for service disconnects to be either be in separate enclosures, or in separate sections of the same enclosure, so that you can work on one at a time, without the others being exposed. This applies if the disconnects of this bank of meters is your up-to-6 service disconnects that are allowed. They now have to be partitioned from each other, so that it is possible to only open the dead front of one of them at a time. You no longer can use a standard MLO panel as a hot-bus panelboard of your 6 service disconnects, or a meter/main with multiple disconnects, where 2020 applies, unless it is built with the partitions
....
There are no plans for any manufacturer to build a meter center with the partitions because of this accepted first revision for the 2023 code.
Detail FR-7799
(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. Separate enclosures with a main service disconnecting means in each enclosure.
  2. Panelboards with a main service disconnecting means in each panelboard enclosure.
  3. Switchboard(s) where there is only one service disconnect in each separate vertical section where there are barriers separating each vertical section. Barriers shall be provided between each vertical section to maintain the inadvertent contact protection required in 230.62 based on access from the adjacent section(s).
  4. Service disconnects in switchgear, transfer switches, or metering centers where each disconnect is located in a separate compartment.
  5. Metering centers with a main service disconnecting means in each metering center.
  6. Motor control center(s) where there is only one service disconnect in a motor control center unit and a maximum of two service disconnects provided in a single motor control center. Barriers shall be provided between each motor control center unit or compartment containing a service disconnect to maintain the inadvertent contact protection required in 230.62 based on access from adjacent motor control center unit(s) or compartment(s).
Exception to (2), (3), (4), (5), and (6): Existing service equipment, installed in compliance with previous editions of this Code that permitted multiple service disconnecting means in a single enclosure, section, or compartment, shall be permitted to contain a maximum of six service disconnecting means.

While it is possible that this will change, there were no public comments other than one to delete the proposed exception, so this is likely to to appear as shown in the 2023 code.
 
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