ECN Forum
Posted By: Steve T 384-16 (1999 NEC) - 05/17/03 02:27 PM
Is anyone familiar with a product by a company called EPC out of Anaheim, CA?

They make a modular, gangable metersocket/panelboard.

The main buss which runs through the metersockets is rated at 400 amps.

The panels are rated at 125A, manuf. prewired, MLO, 6 branch circuit spaces.

This application is typically used in multi-unit apartment buildings. A main service feeds the building and then feeders (usually 200 to 400 amps) are brought to several locations to feed however many of these metersocket/panel combos are ganged together, which is typically around 6 to 8.

Do these panels need main breakers?

Exception No. 2 says for existing installations the main at the panel is not necessary. If this equipment is installed new, but the building is existing and additional circuits are not being added, would this Exception apply?

I believe it is a new installation which would require a main breaker. But why would a manufacturer make something that can't be used without modification?

I am currently waiting on a response from UL as well on this.
Posted By: DJF Re: 384-16 (1999 NEC) - 05/17/03 04:46 PM
At this time I can only give you the 1999 NEC sections (2002 book some where else): 230-71(a) ...no more than six disconnects per service grouped in any one location." 230-79(c) "One-Family Dwelling.-....the service disconnecting means shall have a rating of not less than 100 amperes, 3 wire." and 230-79(d) "All Others"...the service disconnecting means shall have a rating of not less than 60 amperes."
The Service Conductors must be of the same ampacity you get by adding the numeric value of the breakers in the enclosure per 230-80 and as long as it is listed/labeled/tested for the use (Rated as Service Equipment).

Hope this helps

[This message has been edited by DJF (edited 05-17-2003).]
Posted By: Steve T Re: 384-16 (1999 NEC) - 05/28/03 12:38 AM
No actually that doesn't help me much, no offense.

I need to know if a lighting and appliance branch circuit panel rated at 125 amps does not need a main breaker if it is only a six space breaker panel.
Posted By: Steve T Re: 384-16 (1999 NEC) - 05/28/03 12:43 AM
Also, UL told me the equipment is approved under the standard for Enclosed Industrial Control Panels which they told me is not a standard used to test residential service or distribution equipment. I believe the Standard listing is in the White book under NIWT (this may be wrong), but it should be tested to standard QFOF--Modular Panelboards.
Posted By: caselec Re: 384-16 (1999 NEC) - 05/28/03 03:23 AM
Steve

These panels could not be used as lighting and appliance panels but they could be used as power panels 384-16(b). I'm not sure how practical this would be in an apartment situation but out here on the west coast we often use a similar set up to feed single family dwellings. We will use a combination device that has a meter socket and a 4-12 position loadcenter with no main breaker. We will use 4 of the positions to feed 2 sub panels, 4 positions to feed 2 a/c units, 2 positions for the pool panel, etc.

Curt
Posted By: Redsy Re: 384-16 (1999 NEC) - 05/28/03 10:53 AM
Steve,
The '99 NEC Handbook clarifies exception 2 "The phrase "for existing installations" means the existing panelboard." and "...for installation of new panelboards in new or existing residential occupancies, a (split-bus) six disconnect panelboard is not permitted for the service equipment."

Are we confusing a main OCPD with a Service Disconnect?
The panelboard main OCPD doesn't have to be an integral part of the panel, it can be at the feeder source (MDP?).
You say that a main service feeds the building. What does the service equipment consist of ?

Another issue that may arise if the meter combo is a remote "sub panel" is whether the neutral terminal is bonded to the can.



[This message has been edited by Redsy (edited 05-28-2003).]
Posted By: Steve T Re: 384-16 (1999 NEC) - 05/29/03 03:10 AM
The meter/panel ganged combos are fed typically from an MDP. In a large building the MDP/service disconnect will have a single main OCPD, then feeders to different locations throughout the building to feed different groups of the meter/panel combos.

A smaller building may have an MDP/service disconnect with 2 to 6 OCPD's that then feed the locations of groups of meter/panel combos.

The meter/panel combos specifically say "Not suitable for use as service equipment", so the neutrals are not bonded to the enclosure.
Posted By: Redsy Re: 384-16 (1999 NEC) - 05/29/03 11:18 AM
I believe that a "main" OCPD is not required in the panel, because it is provided at the point of feed (the MDP).
Posted By: Steve T Re: 384-16 (1999 NEC) - 06/02/03 02:34 AM
But the OCPD is going to be between 200 to 350 amps and the panels are only rated at 125 amps.

Doesn't the topic of this thread require a maximum of a 125 OCPD ahead of the panel?
Posted By: Redsy Re: 384-16 (1999 NEC) - 06/02/03 11:01 AM
SteveT,
Sorry, I lost track of the exact wording of the question.
I forgot that the feeder would be feeding multiple units. I think that if the feeder is sized based on the demand, and protected at it's ampacity, the meter combos won't require mains.
Time to seek prior approval!
Posted By: DJF Re: 384-16 (1999 NEC) - 06/02/03 12:18 PM
Steve
I believe 230-71)a) still applies unless by "feeders" from the Service you are indicating that the Utility Service drop terminates into a Main Disconnect and then feeders are brought to each meter bank (this is usually not allowed).
But if you mean that the Service hits the structure then is bussed along the building and you have 8 Meters in one location being supplied from this single Service then by your example, I believe, you would have 36-48 Means of Disconnect per Service.
The 2002 NEC Handbook has several pictures addressing some different types of configurations. I think Exhibit (picture) 230.4 may pertain to your situation (page 129)
Just my opinion. I'm not trying to "butt" in on your situation or decision but I hope this helps narrow it down for you.

[This message has been edited by DJF (edited 06-02-2003).]
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