Fusible safety switch or 600A OCPD?

[jaylectricity]

I'm installing a 6-position meter socket. I'm feeding it with 600A 3ph. Do I need a safety switch with the giant lever and three fuses inside or would a 3ph 600A breaker be OK? They mostly serve the same purpose, but I could see why having a lockable lever might be beneficial.

Got a quote on all the equipment with the safety switch for $9000 (not sure if it even included the fuses) from one place, but a quote for about $6000 using a breaker instead from another place.

Don't get caught up on the total number on the quote, it includes some other equipment not mentioned here.

 

[tom baker]

What is the available fault current?
A fused disconnect with FRS fuses is good for 100,000 AIC, need to check the let thru current.
If your available fault current is say 20,000 AIC, then a circuit breaker should be fine.

 

[jaylectricity]

What is the available fault current?
A fused disconnect with FRS fuses is good for 100,000 AIC, need to check the let thru current.
If your available fault current is say 20,000 AIC, then a circuit breaker should be fine.

I'll have to check the Eversource guide, but I can't imagine it would be more than 20,000. But I'm not well versed in that part of it, I don't usually do anything more than residential 200A services.

You can check my profile under "threads started by" to see another thread about this particular service.

Edit to just add the other thread link:

http://forums.mikeholt.com/showthread.php?t=181463

 

[iwire]

Do I need a safety switch with the giant lever and three fuses inside or would a 3ph 600A breaker be OK? They mostly serve the same purpose, but I could see why having a lockable lever might be beneficial.

Generally if you are using meter stacks and opt for a main CB ahread of it the enclosure will have a spot for a lock.

If not you can add one as an option.

Not to go to far off track but supplying six 100 amp meters with a 600 amp feeder seems way overkill.

 

[jaylectricity]

Generally if you are using meter stacks and opt for a main CB ahread of it the enclosure will have a spot for a lock.

If not you can add one as an option.

Not to go to far off track but supplying six 100 amp meters with a 600 amp feeder seems way overkill.

It's 5 200A and 1 40A. 3ph in, 1ph out.

 

[petersonra]

Every time I have run the numbers a circuit breaker of that size ends up being less expensive. Unless you have an unusually high Short Circuit current rating requirement.