84 v from remote earth and ground rod

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CLAG

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Location
Texas
Occupation
Electrician
I have L1 L2 L3 and G
running from a 277/480 generator ( it is not grounded) to a disconnect (which has a connection to a ground rod)
The disconnect feeds a panel board( which has no line to neutral loads ) the panel board feeds a 208/ 120transformer
The transformer is grounded to the same ground rod as the disconnect and it
Has the system bonding jumper
So I have l1 l2 l3 n and g in the panel board
The panel board is feeding some 208v light poles and each pole has an auxiliary ground rod
The problem is that if I measure from remote earth to the ground rod I got 85 v
The lights poles flickers and after a while the breaker trips
I found out that in the 208 /120 panel board had the main bonding installed so I removed it and I thought that was the problem but it's still doing the same thing
All this is really close to transmission lines
Thanks for your time
I'll really appreciate your help thanks
 
CLAG said:
I have L1 L2 L3 and G
running from a 277/480 generator ( it is not grounded) to a disconnect (which has a connection to a ground rod)
The disconnect feeds a panel board( which has no line to neutral loads ) the panel board feeds a 208/ 120transformer
The transformer is grounded to the same ground rod as the disconnect and it
Has the system bonding jumper
So I have l1 l2 l3 n and g in the panel board
The panel board is feeding some 208v light poles and each pole has an auxiliary ground rod
The problem is that if I measure from remote earth to the ground rod I got 85 v
The lights poles flickers and after a while the breaker trips
I found out that in the 208 /120 panel board had the main bonding installed so I removed it and I thought that was the problem but it's still doing the same thing
All this is really close to transmission lines
Thanks for your time
I'll really appreciate your help thanks
Click to expand...
Do the light poles have an EGC pulled and connected to the pole?

Maybe just a faulted 2-wire circuit with a useless ground rod that was supposedly suppose to clear a ground fault.
 
CLAG said:
... The problem is that if I measure from remote earth to the ground rod I got 85 v

... All this is really close to transmission lines
Click to expand...
Did you measure the voltage from remote earth to ground rod with the generator or disconnect shut OFF vs. when they're ON to see what difference it would make?
 
synchro said:
Did you measure the voltage from remote earth to ground rod with the generator or disconnect shut OFF vs. when they're ON to see what difference it would make?
Click to expand...
No I didn't :(
I was a little frustrated thinking about the connections to ground that I dint think on that but tomorrow I'll do the test
 
A lot of the original description is clear as mud. For instance-
277/480 generator ( it is not grounded) (No equipment groundING conductor?, is the neutral brought to the disco?)
to a disconnect (which has a connection to a ground rod) (From the generator neutral or ???)

I found out that in the 208 /120 panel board had the main bonding installed so I removed it and I thought that was the problem but it's still doing the same thing
Is there a bonding jumper then from the transformer XO to the GES?

It sounds as if the EGC's are haphazardly connected. I'd start by tracing every ground wire with an eye to "where do the fault currents go?", if a lighting circuit faulting to the EGC can't trip the breaker, there's a large problem. Could also be that there are already branch circuit faults that a grounding problem is masking.
 
zbang said:
A lot of the original description is clear as mud. For instance-
277/480 generator ( it is not grounded) (No equipment groundING conductor?, is the neutral brought to the disco?)
to a disconnect (which has a connection to a ground rod) (From the generator neutral or ???)

I found out that in the 208 /120 panel board had the main bonding installed so I removed it and I thought that was the problem but it's still doing the same thing
Is there a bonding jumper then from the transformer XO to the GES?

It sounds as if the EGC's are haphazardly connected. I'd start by tracing every ground wire with an eye to "where do the fault currents go?", if a lighting circuit faulting to the EGC can't trip the breaker, there's a large problem. Could also be that there are already branch circuit faults that a grounding problem is masking.
Click to expand...
Sorry I'll try to say it as clear as I can The generator doesn't have a ground rod
Then I have l1 l2 l3 and equipment grounding conductor (which is bonded to the neutral )going to a 3phase disconnect
So I have l1 l2 l3 and equipment grounding conductor in the disconnect so it is grounded ( connected to a ground rod at the disconnect )
Yes it had the system bonding jumper at the transformer and at the panel board as well
 
CLAG said:
Sorry I'll try to say it as clear as I can The generator doesn't have a ground rod
Then I have l1 l2 l3 and equipment grounding conductor (which is bonded to the neutral )going to a 3phase disconnect
So I have l1 l2 l3 and equipment grounding conductor in the disconnect so it is grounded ( connected to a ground rod at the disconnect )
Yes it had the system bonding jumper at the transformer and at the panel board as well
Click to expand...
I'm not seeing a neutral in the feeder mentioned.
 
Where is the system bonding jumper for the Generator? A Floating neutral to a rod does not bond it. Doesn't matter if you have no neutral load, it must be bonded somewhere. At the Gen or at the Disconnect. Not both.

Like this?
Gen to Gen disconnect: Three phase conductors, one floating Neutral, one EG bonded to Gen. System bonding jumper in the Gen disconnect. GES.
Gen Disconnect to transformer: Three phase conductors to primary One EG to Xfmr frame.
Transformer Secondary to Tran disconnect: Three phase conductors, one floating Neutral, one EG bonded to frame.. Secondary bonding jumper in the Tran Disconnect. GES.
Branch Circuits to poles. Phase conductors and EG. Supplementary rods as desired.

ETA: As Dave suggests, your 87 volts to remote earth could be coming from the floating Gen neutral and has nothing to do with the tripping breakers
 
ActionDave said:
Forget about remote earth.
What breaker trips?
What other voltage tests did you make?
Is this a problem that affects all the
Click to expand...

CLAG said:
I have L1 L2 L3 and G
running from a 277/480 generator ( it is not grounded) to a disconnect (which has a connection to a ground rod)
The disconnect feeds a panel board( which has no line to neutral loads ) the panel board feeds a 208/ 120transformer
The transformer is grounded to the same ground rod as the disconnect and it
Has the system bonding jumper
So I have l1 l2 l3 n and g in the panel board
The panel board is feeding some 208v light poles and each pole has an auxiliary ground rod
The problem is that if I measure from remote earth to the ground rod I got 85 v
The lights poles flickers and after a while the breaker trips
I found out that in the 208 /120 panel board had the main bonding installed so I removed it and I thought that was the problem but it's still doing the same thing
All this is really close to transmission lines
Thanks for your time
I'll really appreciate your help thanks
Click to expand...
Hello everyone thanks
CLAG said:
I have L1 L2 L3 and G
running from a 277/480 generator ( it is not grounded) to a disconnect (which has a connection to a ground rod)
The disconnect feeds a panel board( which has no line to neutral loads ) the panel board feeds a 208/ 120transformer
The transformer is grounded to the same ground rod as the disconnect and it
Has the system bonding jumper
So I have l1 l2 l3 n and g in the panel board
The panel board is feeding some 208v light poles and each pole has an auxiliary ground rod
The problem is that if I measure from remote earth to the ground rod I got 85 v
The lights poles flickers and after a while the breaker trips
I found out that in the 208 /120 panel board had the main bonding installed so I removed it and I thought that was the problem but it's still doing the same thing
All this is really close to transmission lines
Thanks for your time
I'll really appreciate your help thanks
Click to expand...
Hello everyone
I just want to say that I really appreciate your help !
Yesterday and today I did not go to troubleshoot that job
But one of my co-workers went today and he decided to install the auxilary ground rods first and then fix the problem and he told me that when he was installing the gec at the auxiliaries ground rods he said that when the wire made contact with the rod it made an arc!
after a while he decided to remove the connection to ground at the disconnect and he went back to the auxiliary ground rods and the arc disappeared and the breaker for the light poles did not trip again
But I feel that something else is going on there
 
CLAG said:
Hello everyone thanks

Hello everyone
I just want to say that I really appreciate your help !
Yesterday and today I did not go to troubleshoot that job
But one of my co-workers went today and he decided to install the auxilary ground rods first and then fix the problem and he told me that when he was installing the gec at the auxiliaries ground rods he said that when the wire made contact with the rod it made an arc!
after a while he decided to remove the connection to ground at the disconnect and he went back to the auxiliary ground rods and the arc disappeared and the breaker for the light poles did not trip again
But I feel that something else is going on there
Click to expand...
Yes, there is.
 
CLAG said:
Hello everyone thanks

Hello everyone
I just want to say that I really appreciate your help !
Yesterday and today I did not go to troubleshoot that job
But one of my co-workers went today and he decided to install the auxilary ground rods first and then fix the problem and he told me that when he was installing the gec at the auxiliaries ground rods he said that when the wire made contact with the rod it made an arc!
after a while he decided to remove the connection to ground at the disconnect and he went back to the auxiliary ground rods and the arc disappeared and the breaker for the light poles did not trip again
But I feel that something else is going on there
Click to expand...
Is there an EGC pulled and connected to the metal poles??
 
Here is a thought. Did someone install lights as a 277 rather than 480? If so these lights are trying to use the EGC as a neutral.
 
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