Loads in series SOLVED

Hello. Im having two 24 volt fans that I need to power up and run simultaneously with both having same speed.

I have a single 48 volt power supply with plenty of power for the fans. The thing is I've never really built anything and only read about electronics in theory.

So my question is: is there something I need to consider when running both fans in series from the power supply or should it work just beautifully?

by niilo22
January 24, 2019

1 Answer

Answer by mikerogerswsm

When a simple dc motor starts, it needs to be able to draw a high current from the supply to provide starting torque until it speeds up and the back emf equals the supply voltage.

By putting two motors in series neither has a fixed supply voltage. One might start first and run too fast and the other would be starved of starting current.

Under fault conditions one fan might become mechanically or aerodynamically stalled which would reduce its back emf to zero and put the full voltage across the other.

Better to run both motors from fixed supply voltages.

ACCEPTED +2 votes
by mikerogerswsm
January 24, 2019

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