600 amp Eaton safety switch removal/replacement

[Sparky_ron]

My customer has a EATON DG326NRK 600A fusible 3-pole 250V SAFETY SWITCH. So, the other day one of the fuses literally caught on fire (instead of blowing) and started a small fire inside of the enclosure.. it mainly melted the plastic section around the copper blades. There are 3” conduits coming into the top, bottom, and sides of the enclosure.
QUESTION: Rather than replacing the whole Nema3 enclosure and removing all or some of the conduits to be able to take it out, I was hoping I could change out the interior guts & safety handle, and install the new guts and handle from an [identical] safety switch. It looks pretty simple. There’s 5/16 bolts from the can to the backing that holds the fuse holders, that part should come off really easily. My concern was where it attaches to the handle and being able to remove that also.

Has anyone ever attempted this? If so can you reach out and tell me how it went. Thank you Ronnie

 

[TwoBlocked]

My customer has a EATON DG326NRK 600A fusible 3-pole 250V SAFETY SWITCH. So, the other day one of the fuses literally caught on fire (instead of blowing) and started a small fire inside of the enclosure.. it mainly melted the plastic section around the copper blades. There are 3” conduits coming into the top, bottom, and sides of the enclosure.
QUESTION: Rather than replacing the whole Nema3 enclosure and removing all or some of the conduits to be able to take it out, I was hoping I could change out the interior guts & safety handle, and install the new guts and handle from an [identical] safety switch. It looks pretty simple. There’s 5/16 bolts from the can to the backing that holds the fuse holders, that part should come off really easily. My concern was where it attaches to the handle and being able to remove that also.

Has anyone ever attempted this? If so can you reach out and tell me how it went. Thank you Ronnie

A concern when doing that is the carbon left in the box from the fire. That can increase an arc flash hazard in the future.

 

[petersonra]

A concern when doing that is the carbon left in the box from the fire. That can increase an arc flash hazard in the future.

He should be able to clean most of the soot away. I don't see how some surface debris increases the risk of arc flash anyway. The enclosure is made of metal that is far more conductive than any surface soot left in place after even a less than thorough cleaning.

 

[Sparky_ron]

There is no carbon on the back part of the enclosure because the fuse holders sit on a raised metal flange, (which will be coming out) There is a some mild residue on the back of the doors cover, but we will be taking that off.
I was merely asking if anyone has ever successfully removed the switching mechanism from a large disconnect.

 

[Choice_Gorilla]

What condition are the conductors in? Are you re pulling new ones?

 

[Eddie702]

Why not buy an identical switch and see if you can pull the guts out of it? You probably can and if not change the switch.

I admit pulling the wires back is a problem. You could always cut a couple of the conduits back and use a couple of short pieces of wireway to get the wires back into the panel. Use a chase nipple between the panel and the wireway.

Maybe a phone call to Eaton is in order.

 

[Sparky_ron]

The conductors are fine. I am going to buy another switch and try to change out the interior. That’s what I said in my original original post.

 

[Sparky_ron]

This is what the interior looks like. I’m thinking I can just unbolt it and swap it out, has anyone ever done this?

 

[garbo]

Back in the 1970's I worked in a large slaughter house that had the old bullet proof best in class Bulldog safety switches. They had over 40 fused safety switches in one of thier garages to plug in truck refers. Several times a year a 30 to 200 amp Bulldog safety switch contact or fuse block would burnt up. We stocked replacement guts that only took a few minutes to rep!ace. Do not remember having any problems on them. Have these Bulldog safety switches in some what harsh environments like dusty damp basement stock yard, rendering plant, kill floor & chill boxes just above freezing temperature. I think the use of quality time delay fuses help safety switches last longer. In one of the hot boiler rooms we found the Shawmut brand of buses that had what we were told silver plated contact area would be the only 30 amp fuse that did not blow a few times a year.

 

[Sparky_ron]

Back in the 1970's I worked in a large slaughter house that had the old bullet proof best in class Bulldog safety switches. They had over 40 fused safety switches in one of thier garages to plug in truck refers. Several times a year a 30 to 200 amp Bulldog safety switch contact or fuse block would burnt up. We stocked replacement guts that only took a few minutes to rep!ace. Do not remember having any problems on them. Have these Bulldog safety switches in some what harsh environments like dusty damp basement stock yard, rendering plant, kill floor & chill boxes just above freezing temperature. I think the use of quality time delay fuses help safety switches last longer. In one of the hot boiler rooms we found the Shawmut brand of buses that had what we were told silver plated contact area would be the only 30 amp fuse that did not blow a few times a year.

Rendering plant, kill floors? Ugh… I’ll bet that was a nasty environment to work!

 

[tortuga]

the other day one of the fuses literally caught on fire (instead of blowing) and started a small fire inside of the enclosure..

Perhaps that phase is overloaded. I'd also want to check why that happened before I replace stuff. Like the load, load balancing and the AFC.

 

[Sparky_ron]

Perhaps that phase is overloaded. I'd also want to check why that happened before I replace stuff. Like the load, load balancing and the AFC.

Did that already, in fact that’s the first thing I did after I replaced the fuse, the fuse should’ve blown regardless…
It’s a 6 tenant lease space with only one space occupied, the rest of the spaces are vacant, the service is rated for 600A and with everything running, the most I got on each leg was 35 A.
Again, I’m simply asking on tips for changing out the guts.

 

[PaulMmn]

Any legal implications? No longer UL approved??

 

[qcroanoke]

Again, I’m simply asking on tips for changing out the guts.

You're new here aren't you?
We never answer a question without asking starting a game of 20 questions or what ifs..

 

[Sparky_ron]

You're new here aren't you?
We never answer a question without asking starting a game of 20 questions or what ifs..

No, I used to have a different username years ago, I’ve been in the trade for almost 40 years (since 1985), I use the formum all the time, just new username.

 

[Sparky_ron]

Any legal implications? No longer UL approved??

I wouldn’t think so, same for same

 

[Sparky_ron]

I wouldn’t think so, same person same

Sorry same for same

 

[tortuga]

the service is rated for 600A

Your probably aware but from your photo the fuses look to be 400 Amp ECNR's.

The other thing I see in the photo is it looks like waters been getting in there, especially on that neutral, so you might check on that before replacing the guts.

 

[Sparky_ron]

Your probably aware but from your photo the fuses look to be 400 Amp ECNR's.

The other thing I see in the photo is it looks like waters been getting in there, especially on that neutral, so you might check on that before replacing the guts.

 

[Sparky_ron]

Yeah, you’re right, they do have 400 amp fuses, but it’s a 600 amp disconnect, the first time I went over there, they had fluctuating/inconsistent voltages on all three phases, it ended up being the line side neutral was overly corroded. I cut back on the wire and restripped it, then moved it to the parallel lug next to it and the voltage went back to normal. The inside of the disconnect is dry, which is weird. I don’t know where the moisture was coming from, the disconnect definitely needs to be replaced.