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Control of multiple motors using one controller

Control of multiple motors using one controller

Control of multiple motors using one controller

(OP)
Hello,

I'm working through a scenario where we have one (1), motor control panel controlling three (3), effluent pumps, in a lead-lag operation. Each effluent pump is 1/2 HP, 240V, 1-phase, 7 Amp. FLA. The motor control panel is rated to control the applicable three (3), effluent pumps.

I wanted to inquire if the electrical code may allow using one (1), 40A, 1-phase, 2-Pole branch circuit and over-current protection to feed all the three (3), effluent pumps via splicing/tapping. Also, the main feeder would be rated at 40A, however the tapped conducters to feed each pump would be rated at 20A because the pump FLA is 7 Amps. Is this acceptable or do the tapped conductors to feed each pump is also required to be rated for 40A?

Thank you.

RE: Control of multiple motors using one controller

Yes, you can bring in a single higher current feed and then split it to smaller current feeds using splitter blocks and fuses.

RE: Control of multiple motors using one controller

Check the code.
Under the Canadian Code:
Rule 14-100 Individual fuses may not be required. The length of undersized tap conductors may be limited.
Rule 12-2000 A splitter may not be needed if the conductors are #6 AWG or smaller.
Rule 28-108 Conditions for multiple motors on a single feeder.
Your local code probably has similar provisions.

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

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