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Hello Superelecon


This really depends on what type of starter you intend to use, but firstly, for each motor, you need to have overload protection and an automatic means to disconnect the motor in event of an overload. This requires at a minimum, one contactor and thermal overload per motor, so you have effectively a DOL (Direct On Line) starter per motor. If you wish to use one soft starter for all three pump motors, you will need to have two contactors and one thermal overload per motor in addition to the soft starter. Plus you will nedd some sort of controller to control all the contacotrs etc in the correct manner. By the time you put all this together, it is usually cheaper to have one soft starter per motor!!


Best regards,

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Wire them in parallel.


As long as you want them to all come on and off at the same time, there is nothing inherently wrong with that. But each motor must have it's own overload protection, and if the motor starter is the only wat to have an OL relay turn the motor off, you must have the OL realy contacts in series so that if any OL trips, all of the pumps will shut dowm. The alternative would be to have a separate Motor Protection Switch on each motor that has it's own trip device that will open the motor power circuit if it detects an overload.


Also, if your pump motors are internally protected you may not need to worry about that.

"He's not dead, he's just pinin' for the fjords!"
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