Service Riser/Lateral

[Dan Blanchard]

The code check book, fourth edition, page 24 under services states: clamp conduit within 3ft of service box, T3702.1. Looking at the table on page 501 of 2006 IRC, for clarification, I don’t find what I’m looking for. “Clamp conduit within 3ft of service box” are they talking about installing a clamp on the exterior conduit to the exterior of the dwelling within three feet of meter? Exactly what are they talking about?
Thanks

[Jerry Peck]

It means that the conduit must be both secured and supported within 3 feet of the box.

On that same Table, on that same page, look up EMT, IMC, RMC, then also look over one more column to ENT, in the top heading, then go down to the bottom line in the table: "Maximum support distance in inches from box or other terminations.", you will see "36" inches for both columns.

[Wayne Carlisle]

“Clamp conduit within 3ft of service box” are they talking about installing a clamp on the exterior conduit to the exterior of the dwelling within three feet of meter? Exactly what are they talking about?
Thanks

That's exactly what they are talking about. By clamping it (securing) it keeps the weight of the wires coming from the utility pole from pulling the service mast away from the structure and the meter base.

[Dan Blanchard]

So that would be 36" above or below the box. Say the box is 48" above ground with underground service, one clamp would be required? One more electrical question. Can the main service panel be installed upside down? A master electrician that teaches electrical here in town says no and an instructor at a "new construction to code" class says yes. I have been through the 2008 National Electrical Code Book and I can not find where it is a violation to install a main service panel upside down.
Thanks again

[Rick Cantrell]

The breakers (Think main breaker), should not be installed in a manner that;
UP is OFF, and DOWN is ON.

[Jerry Peck]

So that would be 36" above or below the box. Say the box is 48" above ground with underground service, one clamp would be required?

Correct.


Can the main service panel be installed upside down? A master electrician that teaches electrical here in town says no and an instructor at a "new construction to code" class says yes.

No ... and ... yes.

Yes. First, I will explain: Most (if not all) interior panel enclosures (service equipment or otherwise) is designed to be able to be installed ... either end up.

The breakers, though *MUST NOT* be installed with *ON* in the down position, but the panel interiors which go in the panel enclosures are made to accommodate that - in most cases.

No. If it is an exterior enclosure, there is *only one up* direction, so that would not be allowed to be installed upside down (or downside up either).


I have been through the 2008 National Electrical Code Book and I can not find where it is a violation to install a main service panel upside down.

110.3(B) is your code reference.

[Frank Mauck]

Dan,

If the Meter Hub is 48 inches above the ground, the conduit that is installed in the bottom of the Hub and going into the ground is probably for the Power Company's Service Lateral Conductors and thar conduit is the property of the Power Company and will be exempt from the codes, NEC 90.2(B)(5) or IRC E3301.3

[Jerry Peck]

is probably for the Power Company's Service Lateral Conductors and thar conduit is the property of the Power Company and will be exempt from the codes, NEC 90.2(B)(5) or IRC E3301.3


Not in all areas, and, in fact, most areas have been converting over to those being owner owned, not power company owned.

The power company owns the meter, but in most case, the homeowner now owns the meter box.

Years ago, you could not buy a meter can, the only source was the power company. There were some lawsuits about it (don't recall the details any more) and the power company had to give up that monopoly, giving ownership to the homeowner.

In most cases, the power company still own the overhead service drop conductors and the underground service lateral conductors, but the mast/riser to the overhead service drop and the riser from the underground service now belong to the homeowner.

Which means those things fall under the AHJ, which means the code.