Service overcurrent protection for 4 unit apartment.

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rhovee

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The way the service is set up now is the service entrance conductors come from over head into a 400 amp fuse disconnect that has 225 amp fuses in it. Out of that disconnect it nipples into a bus gutter and then each if the units are tapped off of this to a meter and meter to main breaker in panel. My question is. If I replace the disconnect with a new one does it have to have over current protection in it or can it just be a disconnect since I have overcurrent protection in each panel with less than 6 disconnects.
 
You haven?t mentioned the location of any of the equipment.
Is the 225 disconnect inside
Is the 225 amp disconnect the service disconnect
Where are the meters in relationship to the 225 amp disconnect?
Where are the panels being feed from the meters?
 
All of the equipment is inside. One problem I see already is that the disconnect is before the meters. So someone could shut the disconnect off and tap off a new feed with no meter. I think I should call the ahj on this one. And yes the 225 is the main disconnect. The. Nipple to a bus gutter. Then out of the bus gutter it goes nipple meter nipple panel to main breaker.
 
If you do not have a disconnect with OCPD, the wires remain service wires and must be sized for the full total load. Depending on how far the group of meters extends, an AHJ may have a problem with the length of service conductor inside the building.
If the disconnect is not sealed, POCO may have a problem with it as you suggested.
 
I am going to just have to call the local AHJ and see what they are going to require. Not sure how far I need to take it since it is existing. It is my first job as a contractor so definitely don't want to start off on the wrong foot.
 
ActionDave said:
Every jurisdiction does not see it this way.
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The NEC does. Regardless of where the service demarcation is, the wires involved are service conductors up to the service disconnect, which by definition must provide OCPD.
How each AHJ feels about having them inside is known to vary since th NEC neglected to define "closest to". :)
 
GoldDigger said:
The NEC does. Regardless of where the service demarcation is, the wires involved are service conductors up to the service disconnect, which by definition must provide OCPD.
How each AHJ feels about having them inside is known to vary since th NEC neglected to define "closest to". :)
Click to expand...

Disclaimer: I am going to be a bit nit picky here. I disagree that "by definition" the service disconnect must provide OCPD. 230 basically states that a disconnecting means is required. Then a little later it states that an OCPD is required. Then it states that the OCPD shall be an integral part of the service disconnecting means or located "immediately adjacent thereto"

To the OP: I have seen what you describe many times without a service disconnect before the bus gutter and meters. Depending on the specifics of the layout, I could see the disconnect ahead of the bus gutter as completely un-necessary and a waste of money. You would have 2-6 (grouped) service disconnecting means instead of 1.
 
GoldDigger said:
The NEC does. Regardless of where the service demarcation is, the wires involved are service conductors up to the service disconnect, which by definition must provide OCPD.
How each AHJ feels about having them inside is known to vary since th NEC neglected to define "closest to". :)
Click to expand...
Yes, and also why things get to be a mess when Cold Sequence is required by POCO and the AHJ calls the first disconnect, fused or unfused the service disco.
 
In the '08 Code, 230.82(3) calls them "meter disconnect switches" and they are "allowed ahead of the service equipment". Often required by POCO but usually locked & controlled by POCO also.
 
fmtjfw said:
New term to me, what does it mean?
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Hot sequence. (Pretty much every home in the US)

Utility > service point > metering > service disconnect with overcurrent protection > panelboard

Cold sequence. (Now being required by many power companies when the voltage exceeds 250 volts to ground or 300 volts line to line.)

Utility > service point > service disconnect with overcurrent protection > metering > panelboard.

The problem with the above is some power companies want to put their seal / lock on the service disconnect to protect them from theft of power. However that makes the OCPD inaccessible to the customer. So the NEC now allows a 'meter disconnect' and if you install one it goes like this.

Utility > service point > meter disconnect (no OCPD) > metering > service disconnect with overcurrent protection >panelboard.
 
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