Some inspectors and myself are having a disagreement.
Scenario: Murray 200A combo panels (meter, main,distribution) require a 2" hub. One of the inspectors says "logic would follow that a 2-inch mast is required" and he is making electricians prove a 1-1/2 mast is OK.
My argument: This inspector is 'assuming' too much. Just because Murray chooses to simplify their manufacturing process (just one size hub to mfr. and supply for distribution) doesn't mean Murray is mandating a 2" mast (this 2" mast requirement is not in the mfr. written installation instructions that I am aware of). As far as I'm aware there is a 2 x 1-1/2 reducer bushing available and none of us (who are arguing this matter) have found a code section that does not permit a bushing at the hub.
Rkeis says: "Make them show it to you in the code".
I say you cannot make 'logical conclusions' about what a mfr. wants if it's not in the written instructions, and there is no code citation.
(No I don't have the particular model number for this panel....one of the guys says he's going to check with Murray.....but then we may be getting into another can of worms - who's he checking with at Murray? I don't think a verbal phone call qualifies as mfr. instructions one way or the other).
...please don't beat me too harshly on this subject...I really am a sensitive caring poet in disguise as an inspector & elect.
Here in NJ, the Utility Co's specify the mast sizes. The last one we did was 2 1/2" The hubs on the meter cans are interchangeable, so it's not a problem. PSE&G supplies meter cans, we change-out the hub if needed. GPU (JCP&L) we have to supply the cans. The "all-in-one" is not common here. HotLine1 John
Re: Service Mast size#81638 09/04/0210:41 AM09/04/0210:41 AM
Correct me if I'm wrong but a service raceway is only a MAST if it projects through or above the roof and the Service Drop is supported by it. Our PoCo requires 2" minimum. If it is only attached to the building as a raceway, you could use as small a size conduit as conductor fill requirements dictate.
Re: Service Mast size#81640 09/10/0209:07 PM09/10/0209:07 PM