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Reduced Voltage Starter removal

Reduced Voltage Starter removal

Reduced Voltage Starter removal

(OP)
Hello:

I am currently trying to write the "working instructions" to remove a reduced voltage starter circuit hooked up to a 100hp motor that activates a fan. The reduced voltage starter has a auto-transformer configuration. Wanted to know if there are any electricians/engineers that know, OR could point me to the direction of step-by-step instructions to remove such a circuit?? I am having a hard to writing down these instructions AND finding someone to assist. I am only focused on the reduced voltage starter circuit and thats it (just basic instructions). Anyone with this knowledge I would appreciate it. Thanks

RE: Reduced Voltage Starter removal

Not really clear on what you're after here. Normally one identifies the system to be removed. With the power proven off you rip it all out as efficiently as you can. Job done. You seem to be asking something 'different'.

Are you replacing the RVS with something? If it was needed that function is still needed.

Keith Cress
kcress - http://www.flaminsystems.com

RE: Reduced Voltage Starter removal

Yeah, I agree. The instructions might include things like "refrain from using explosives, no matter how frustrated you get trying to free that bolt". But otherwise there isn't anything that requires special attention, unless there is something you are leaving out of the story.

If this were a Wye-Delta starter you may need to instruct the demo people to carefully mark the 6 cables going to the motor, that's important later, but an auto transformer will not have that issue.

If you were thinking of trying to maintain the integrity of the starter to re-use it, I'd say don't bother. That transformer is do big and heavy, the only way to effectively remove it will be by completely disconnecting all of the conductors and removing the contractors first. Besides, the starter as a unit isn't worth any heroic efforts to save it, other than as individual parts.


"You measure the size of the accomplishment by the obstacles you had to overcome to reach your goals" -- Booker T. Washington

RE: Reduced Voltage Starter removal

The most important measure will be to isolate the starter from all and any sources of power. Beware that in some designs the control power may be from a separate source and may need to be isolated as well.
The supply circuit(s) should checked and verified that the correct circuit has been isolated. The mere absence of power does not guarantee that the proper circuit has been isolated. Not all plant or industry lock-out procedures recognize this point.
After isolation and verification, the circuits should be secured with locks.
After that, procedures will depend on the construction of the starter and the reason for removal.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Reduced Voltage Starter removal

(OP)
To be clear. I am removing a reduced voltage starter from a stand alone cabinet. It has 480V on the line side and 120 in the control. The 120V comes off a transf which has the 480V as I just mentioned. This type of reduced voltage starter has an "auto transformer configuration on the line side". This is where most of the confusion comes from. I wanted to know if any electrician/engineer/technician that know the procedures/steps to remove a reduced voltage starter with an autotransf configuration. Thats mainly what Im trying to know,.step-by-step instructions. I will be installing a soft starter in its place.

RE: Reduced Voltage Starter removal

brock1155,
Here:
1. Lock-out and tag-out the equipment.
2. Remove the cables tapped at the load side of the circuit breaker.
3. Remove the motor lines connected to the RV starter equipment.
4. Remove the RV starter from the cabinet.
5. Release yout LO/TO permit.
END OF JOB.

RE: Reduced Voltage Starter removal

There will be no such thing. Any competent electrician should be able to accomplish the task without step by step directions. The basic procedure is to isolate power and then remove all parts relating to the starter but leave any extra controls that you will still need. Then you install the soft-starter and connect incoming power and motor leads to it's terminals. You will have to sort out your specific control circuitry for re-connecting to the soft-starter.

RE: Reduced Voltage Starter removal

"Any competent electrician should be able to ..." is what the OP is missing - that is, who is the target audience for these instructions?

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