Starter Removal

Alwayslearningelec said:
Wow you are smart. So there are scenarios where there are fuses(as in my pic above) and not breaker? In that case the starter can be removed with no issues? Wiring would have to be modified I assume?
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Yes, fuses are fine, and yes, you would have to extend the conductors from the fuse holder to where your load wires are, because your motor leads are likely too short to reach up to where the fuses are.
 
Jraef said:
Yes, fuses are fine, and yes, you would have to extend the conductors from the fuse holder to where your load wires are, because your motor leads are likely too short to reach up to where the fuses are.
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Thanks so explain the wiring a little more between starter and fuses. The wiring from the motor comes in and hits the starter then the fuses?
 
Alwayslearningelec said:
Thanks so explain the wiring a little more between starter and fuses. The wiring from the motor comes in and hits the starter then the fuses?
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The motor leads likely terminate on the bottom of the motor starter, which is your case is quite a ways from the fuses. So when you remove the starter, the motor leads will most likely be too short to reach. So I would add a stand alone terminal block where they are (because the starter terminal will be removed) then replace those 3 conductors on the load side of the fuse holder to go down to that terminal block.
 
Jraef said:
The motor leads likely terminate on the bottom of the motor starter, which is your case is quite a ways from the fuses. So when you remove the starter, the motor leads will most likely be too short to reach. So I would add a stand alone terminal block where they are (because the starter terminal will be removed) then replace those 3 conductors on the load side of the fuse holder to go down to that terminal block.
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Yes I was thinking based on what you were saying about an extension of wiring(and too short) I would need a splice. Sure splice is not allowed hence terminal block.
 
Alwayslearningelec said:
Yes but this is a different one. But there are fuses here although they look small. Does this MCC have a breaker? Hard for me to tell.
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It does not appear that there is a power circuit OCPD in the enclosure. The fuses on the side are the primary and secondary fuses for the control power transformer.
 
don_resqcapt19 said:
It does not appear that there is a power circuit OCPD in the enclosure. The fuses on the side are the primary and secondary fuses for the control power transformer.
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Agreed, although hard to tell if we are seeing the entire unit in the framing of this photo. If we are, then it’s likely that this is part of a larger assembly where the rest of it is in the adjacent section. Usually there will (should) be done sort of door interlock system to prevent this door from being opened until the other unit with the disconnect device being opened first.

Three contactors in this section likely means this is a large RVAT (Reduced Voltage Auto Transformer) type starter, which means there is a big transformer somewhere. So it could be that the adjacent section has the disconnect (fused or CB) and that transformer, so the contactors are all on this side.
 
Your picture of the entire MCC does not show the starter shown in post #25.
It does show 3 two speed starters (they are the ones with 2 overload resets).
The only way to know the starter buck is fused or a breaker is to open the bucket door. Or, you could get a set of drawings from the factory.
 
Retired from a large hospital that was built in the 1970's so every motor was on a starter. A few lazy electrical contractors left the starters inside of the bucket and used the starter to feed drives they installed. All of our retrofit & new install drives were ordered with disconnect & line fuses inside of drive cabinet. Had 200 & 400 amp fused safety switches right next to drives that feed line reactor then to drives with factory installed line fuses. Had three different brands of MCC'S. A few MCC buckets had fuses rather then a circuit breaker. In that case liked to replace 40 year old original fuses with quality 200 KIC time delay fuses to yet again a drive with factory installed line fuses.
 
jim dungar said:
Your picture of the entire MCC does not show the starter shown in post #25.
It does show 3 two speed starters (they are the ones with 2 overload resets).
The only way to know the starter buck is fused or a breaker is to open the bucket door. Or, you could get a set of drawings from the factory.
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Thanks. Exactly why doesn't it show starters in #25? How do you know, so I can know.
Where exactly do you see THREE two speed starters. I know you say the ones with 2 overload resets but I can't tell which those are.
 
Alwayslearningelec said:
Thanks. Exactly why doesn't it show starters in #25? How do you know, so I can know.
Where exactly do you see THREE two speed starters. I know you say the ones with 2 overload resets but I can't tell which those are.
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The bucket in #25 has a single overload relay reset button on the unit door. None of the large units in #30 have single resets.
 
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