Grounding question - existing condition

Merry Christmas

olc

Senior Member
Here is the situation:
It looks like panelboard PP-2 was the original main service panelboard. At some later date an addition was built and PP-2 became a subpanel (with a new feeder) connected to PP-1 which is at the service. The feeder is in a RGS conduit underground to PP-1. About 20 feet – the width of the addition.
At that time:
The PP-2 connection to a original ground rod was disconnected.
It does not look like the neutral and ground bus were separated in PP-2.
No ground conductor was installed with the 4 wire feeder.

This is the existing condition now that has been in place for many years.
PP-2 is what the panelboard is currently labeled even though it was originally installed before PP-1.

This has come up because we are adding another panelboard for a new small addition that was to be connected to PP-2.

The question – should something be done for the PP-2 grounding?
 
Here is the situation:
It looks like panelboard PP-2 was the original main service panelboard. At some later date an addition was built and PP-2 became a subpanel (with a new feeder) connected to PP-1 which is at the service. The feeder is in a RGS conduit underground to PP-1. About 20 feet – the width of the addition.
At that time:
The PP-2 connection to a original ground rod was disconnected.
It does not look like the neutral and ground bus were separated in PP-2.
No ground conductor was installed with the 4 wire feeder.

This is the existing condition now that has been in place for many years.
PP-2 is what the panelboard is currently labeled even though it was originally installed before PP-1.

This has come up because we are adding another panelboard for a new small addition that was to be connected to PP-2.

The question – should something be done for the PP-2 grounding?
Neutral and ground must be separated in PP-2. An EGC should have been run with the feeder to PP-2.
 
Thanks for the replies.
The conduit is "grounded" on it's way underground to the service.

The panelbd has no equipment grounding bar. Actually it looks like only 4 of the branch circuits (out of many) have equip ground wires - all connected to the neutral bar. I don't know how many of those are shared. Many of the wires (branch circuits) go out in one conduit.
 
Thanks for the replies.
The conduit is "grounded" on it's way underground to the service.

The fact that the conduit is in contact with the earth is not relevant. The issue is the function of the conduit as the EGC to carry fault current back to the ground/neutral bond in the service panel. Continuous RGS can certainly function as an EGC; but I would take the time to insure that you actually have continuous RGS, and not underground PVC with RGS bends and stub-ups.
The panelbd has no equipment grounding bar. Actually it looks like only 4 of the branch circuits (out of many) have equip ground wires - all connected to the neutral bar. I don't know how many of those are shared. Many of the wires (branch circuits) go out in one conduit.

IMHO when PP-1 was added and the service panel converted to PP-2, then the neutral bar should have been insulated from the enclosure and a separate ground bar added.

-Jonathan
 
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