Multiple motors

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TMW

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I have two motors on a circuit but would like to only run one at a time. What type of controls would I need to lock out one while the other is running?
 
What type of control are they on now... magnetic starter, breaker, disconnect ??
 
Much more information is needed. Are you looking to automatically switch loads, and if so, based on what criteria? Are you just looking to use the load calculation for non concurrent loads? Or a way to strictly prevent one motor from running when the other is, etc?
 
Welcome to the forum.

Obviously, you need a mechanism that will physically or electrically prevent simultaneous operation.

As the guys said above, we need to know how the motors are controlled now to advise you how to.
 
The easiest would be a double throw switch with the correct number of poles for your load. If it has a center off position and it can be locked in the off position, it could also be your disconnect for both motors.
 
Strathead said:
Much more information is needed. Are you looking to automatically switch loads, and if so, based on what criteria? Are you just looking to use the load calculation for non concurrent loads? Or a way to strictly prevent one motor from running when the other is, etc?
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It's for trash compactors. The owner doesn't want to provide a larger panel so they want to be able to lock out one motor so the load doesn't impact the panel for both motors.
 
TMW said:
I have two motors on a circuit but would like to only run one at a time. What type of controls would I need to lock out one while the other is running?
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kind of a loaded question. it is not especially difficult to do what you asked but the simpler solutions might not be suitable.
 
probably the simplest solution is to wire in a reversing contactor downstream of the disconnect. Route the reverse side to one compactor, and the forward side to the other. Have a selector switch to select which one you want to energize. the built in mechanical and electrical interlocks that come with a reversing contactor will prevent both from being on simultaneously.
 
Most trash compactors I've seen of any size have magnetic starters. If so, a simple switch in the control should suffice.
 
petersonra said:
I don't think a typical disconnect switch is suitable for use as a motor controller at all.
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Most of the time when the term "disconnect" is used, we are really talking about a "safety switch" and most of those are horsepower rated making them suitable for use as a motor controller.
 
Do you have a picture of the rating plate on these? Geesh your making it hard for us to help. Install a double throw safety switch, you will still need overcurrent protection of some sort.
 
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