Please Help with CT and Service

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shermansfather

shermansfather

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Northeast Ohio
I have a job that involves providing 277/480 for future use to gravel boats. The boats will not be in place for some time, but the service needs to be installed now as the POCO is for a limited time providing the transformer free.

My parameters:
A: Load - Anywhere between 5kw and 100kw per disconnect (x2), maybe peaks of 200kw
B: Connections to disconnect made by ship's electrician, who I'm told keep rated cable, fuses and fuse reducers. I'm to leave fuses out of disconnect after my installation.
C: I'm installing 2 400 A Discos, but POCO is requiring 1600A capacity out of the vault and 1600A CT cabinet.
D: Everything is outdoors, no stucture anywhere

My questions:
A: Before the CT cabinet do I parallel the phases individually (like my drawing), the POCO is telling me to do it his way.

B. Do I bond the neutral to the EGC and electrodes at the CT cabinet or at each disconnect ? I left this off the drawing for now.

C. Would I need a main disconnect before the 2 400A discos (POCO says they usually want a disco before CT's above 800A, their engineer says he'll let it go)

D. Does anybody have any better ideas ?

Flats.jpg
 
shermansfather said:
I have a job that involves providing 277/480 for future use to gravel boats. The boats will not be in place for some time, but the service needs to be installed now as the POCO is for a limited time providing the transformer free.

My parameters:
A: Load - Anywhere between 5kw and 100kw per disconnect (x2), maybe peaks of 200kw
B: Connections to disconnect made by ship's electrician, who I'm told keep rated cable, fuses and fuse reducers. I'm to leave fuses out of disconnect after my installation.
C: I'm installing 2 400 A Discos, but POCO is requiring 1600A capacity out of the vault and 1600A CT cabinet.
D: Everything is outdoors, no stucture anywhere

My questions:
A: Before the CT cabinet do I parallel the phases individually (like my drawing), the POCO is telling me to do it his way. DO IT THERE WAY




B. Do I bond the neutral to the EGC and electrodes at the CT cabinet or at each disconnect ? I left this off the drawing for now AT DISCOS



C. Would I need a main disconnect before the 2 400A discos (POCO says they usually want a disco before CT's above 800A, their engineer says he'll let it go) ID ASK AGAIN !

D. Does anybody have any better ideas ? NO IT LOOKS FINE ! BUT QUESTION WHAT PROGRAM DO YOU USE FOR YOUR LAYOUTS I LIKE THAT .

Flats.jpg
Click to expand...


i like the view and the basic design its a clean looking drawning so whats the program ?
 
In answer to your questions
1.Local POCOs won't accept all phases in one conduit, but if it's agreeable with your POCO it makes for a net job.
2."Normal" here is to ground the CT cabinet by the neutral connections (non-isolated)
3.Be thankful POCO doesn't want the disconnect.
4."Normal" here would be a GEC from each disconnect to the electrode(s)
 
I would have said you need one of each phase and the neutral in each conduit for the parallel, unless it's a non-metallic CT cabinet.

Mark
 
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