clearance issue

[zapped 1]

good afternoon recently i changed the lugs in a 320 mc to double barrel to accomadate a new 200a service for some temp trailers could someone give me a code ref for clearence from the lug to the cover of the mc i only have 1/8 inch due to new lugs being bigger i,m pretty sure the nec says something about this but i can not find it.if it is a violation i will have to fix accordingly. thanks :-?

 

[charlie]

. . . clearance from the lug to the cover of the mc . . .

I think this is what you are looking for, take a look at the table. I think you will need to have a minimum of ?" of clearance, but the exception may apply. :smile:

408.56 Minimum Spacings. The distance between bare metal parts, busbars, and so forth shall not be less than specified in Table 408.56.
Where close proximity does not cause excessive heating, parts of the same polarity at switches, enclosed fuses, and so forth shall be permitted to be placed as close together as convenience in handling will allow.

Exception: The distance shall be permitted to be less than that specified in Table 408.56 at circuit breakers and switches and in listed components installed in switchboards and panelboards.

 

[jim dungar]

good afternoon recently i changed the lugs in a 320 mc to double barrel to accomadate a new 200a service for some temp trailers could someone give me a code ref for clearence from the lug to the cover of the mc i only have 1/8 inch due to new lugs being bigger i,m pretty sure the nec says something about this but i can not find it.if it is a violation i will have to fix accordingly. thanks :-?

Did you use lugs approved by the manufacturer of the equipment?
What is your voltage to ground?

I know in some panel boards, when you purchase 2-barrel stacked lugs, the panelboard manufacturer includes additional insulation because the allowable clearance is compromised.

 

[wawireguy]

1/8" of a inch is not much of a air gap. What happens if someone leans on the cover. If you do this install in this manner I would recommend permenant labeling stating the proximity hazard inside the panel.

 

[charlie]

Quote from Steve Irwin, "Danger!"

Quote from Steve Irwin, "Danger!"

. . . What happens if someone leans on the cover. . .

You are absolutely correct! Depending on the available fault current, someone could be taking a shower in melted copper, aluminum, and steel. That would not be a pretty sight, not to mention the lack of ability to sleep at night after being responsible for the explosion

 

[zapped 1]

thanks

thanks

thank you everyone after careful consideration i have decided to replace the trough which will allow me to tap inside it and put the single lugs back into the meter can

 

[Pierre C Belarge]

thank you everyone after careful consideration i have decided to replace the trough which will allow me to tap inside it and put the single lugs back into the meter can

Caution to the side of safety is not a bad idea....good for you!

 

[charlie]

Good call

Good call

Caution to the side of safety is not a bad idea....good for you!

I second that statement.

 

[Fulthrotl]

You are absolutely correct! Depending on the available fault current, someone could be taking a shower in melted copper, aluminum, and steel. That would not be a pretty sight, not to mention the lack of ability to sleep at night after being responsible for the explosion

and while we are at it, i've seen dry type transformers in the 100kva range
that when you put lugs on them, the luge are less than a half inch from the
cover...... and that is with small hypress lugs!

how does some of this stuff get ul listing? you shoudn't have to make a inner
cover from 1000v. electroliner to go in between the lugs and cover, to be able
to sleep at night after hooking one of these up.....