Buss stabs in need of an EGC.

[chris kennedy]

I have 3 sets of stabs that are fed from POCO. POCO is moving their tranny and I'm installing a 2500A main and ATS before the stabs.

I will be removing the system bonding jumpers from the existing 3 mains and need to hit them with a 350 EGC. The EE missed this on his riser and I just caught it today.

How would you do this?

Thanks
Brain-dead Chris

View attachment 2092

Click on pic.

 

[benaround]

RFI the EE, it's not your call.

 

[iwire]

Chris I am not really following you. If there is an EE involved I would put it in their laps.

 

[chris kennedy]

RFI the EE, it's not your call.

Thats a given, But we know what his answer will be:

'Install a 350 EGC to each 1600A gear and remove the existing system bonding jumpers.'

My question involves the routing of the new EGC.

Chris I am not really following you.

Here is the existing POCO tranny. Behind it you can see 2 of the 3 sets of stabs. These feed 3 existing 1600A mains in the room behind.

POCO tranny will be relocated outside and new 2500A main installed in its place ahead of the 3 existing mains. Here will be the new system bonding jumper.

View attachment 2094

Click on pic

 

[benaround]

Chris, Are you locked in on the price to do this work? If not, would you

consider gutting out what is there and then running conduit from the 2500 to

the (3) 1600's? WAG.

 

[hillbilly1]

Must be in south Florida, we done a bunch of these, except the tranny wasn't moving. We had custom bus plates made for the switch gear that converted to mechanical lugs and did away with the bus out to the transformer, ran new conduit to the transfer switch, then back to the transformer vault to reconnect.

 

[chris kennedy]

Chris, Are you locked in on the price to do this work? If not, would you

consider gutting out what is there and then running conduit from the 2500 to

the (3) 1600's? WAG.

Must be in south Florida, we done a bunch of these, except the tranny wasn't moving. We had custom bus plates made for the switch gear that converted to mechanical lugs and did away with the bus out to the transformer, ran new conduit to the transfer switch, then back to the transformer vault to reconnect.

Thank you both, but both of those scenarios would involve too much down time. This is a broadcast facility and I have 24 hours to make the switch.

 

[benaround]

Chris,

Couple of thoughts:

1. The location in the pictures, is it a seperate structure ?

2. Are you under the 2005 or 2008 NEC

3.Have you considered Cable Tray

 

[hillbilly1]

Thank you both, but both of those scenarios would involve too much down time. This is a broadcast facility and I have 24 hours to make the switch.

We are doing this to a local grocery store chain, and keep the store up while doing the changeover, we use a large trailer mounted generator to keep things running while changing out everything, about a 10 hour period on generator, get the inspection first thing in the morning, and have it back on utility. With grocery stores down time is not an option.

 

[jrannis]

I did one of these where FPL surrended the vault and we moved in.
The vault had a nice existing ground system and we tied onto it.

Chris,
How are you guys going to transition to the vault stabs?

 

[chris kennedy]

I did one of these where FPL surrended the vault and we moved in.
The vault had a nice existing ground system and we tied onto it.

Exact same situation.

How are you guys going to transition to the vault stabs?

Four 3 barrel lugs bolted to each stab with an enclosure built around the whole thing.

1. The location in the pictures, is it a seperate structure ?

2. Are you under the 2005 or 2008 NEC

3.Have you considered Cable Tray

1) This building is mechanical and electrical and serves the larger bldg. about 150' away.

2) 05

3) Sure

Have you ever felt like the Mark Martin of Derick Cope Electric ?

No. (Michigan 2pm EST.)