Question about main bonding jumper

munisparki

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Location
Texas
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Sparky
Installing a temp pole.

Power is supplied from the utility ground transformer to the utility meter. The meter is grounded with it's own ground rod. This is the only ground rod.

Typical 120/240 3 wire split phase coming into a small temporary service panel through a metal conduit.

Panel only has one bus bar where both grounds and neutrals are landed as well as the service neutral.

The single bus bar is for some reason not bonded to the panel enclosure. It is "floating" on a plastic spacer.

There is no main bonding jumper or bonding screw. I'm not that familiar with temp poles but shouldn't the panel enclosure be bonded to the single neutral/ground bus bar with a main bonding jumper?

Or would this cause neutral current to flow from the bus through the MBJ through the metal conduit to the meter?


Also why does this panel have the only bus bar floating and on a plastic fitting?
 
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There is no main bonding jumper or bonding screw. I'm not that familiar with temp poles but shouldn't the panel enclosure be bonded to the single neutral/ground bus bar with a main bonding jumper?

Yes.

Or would this cause neutral current to flow from the bus through the MBJ through the metal conduit to the meter?

It might, but that's allowed on the line side of the service disconnect.

Also why does this panel have the only bus bar floating and on a plastic fitting?

Probably because it can be used either as service equipment or as a subpanel.
 
Installing a temp pole.

Power is supplied from the utility ground transformer to the utility meter. The meter is grounded with it's own ground rod. This is the only ground rod.

Typical 120/240 3 wire split phase coming into a small temporary service panel through a metal conduit.

Panel only has one bus bar where both grounds and neutrals are landed as well as the service neutral.
Their should've been a little off set copper bonding jomper in the box about 3 inches long. It fits into the neutral bar and lines up with a pre-threaded hole to screw it to the panel
 
In reality the metallic nipple to the meter base provides a ground path but, yes, 250.24 requires a MBJ in the service panel.
 
I thought this was all correct but like I said wasn't sure if there is some exception for temp service that I wasn't aware of..

Honestly this temp panel is beat to heck.. it's got to be like 15 years old or something almost falling apart

Thanks fellas I appreciate it
 
I thought this was all correct but like I said wasn't sure if there is some exception for temp service that I wasn't aware of..

Honestly this temp panel is beat to heck.. it's got to be like 15 years old or something almost falling apart

Thanks fellas I appreciate it
No, not for that.
 
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