Water pump and air pump setup to Duet 3 Expansion 3HC
-
Hello
I am planning to set up 12v air pump and water pump (both brushless), just want to make sure that the below setup is right. Would this setup work?
If I connect the brushed DC motors instead of brushless motors, do I need to use flyback diodes ? Do you recommend flyback diodes for the above stepup with brushless motors?
-
This might be relevant
DC42 said:
Please note, we don't advise connecting water pumps directly to fan outputs, because most of them use brushed DC motors, and the surge current they draw is too much for a fan output. We recommend that they are connected to a heater output instead, with a flyback diode in parallel with the motor (make sure you get the polarity of the diode right!). This does not apply if you know that the pump uses a brushless DC motor.
So if you're sure it's brushless than you don't need the flyback.
-
As @Phaedrux says. If you use brushed DC motors instead then I suggest you use the high current outputs OUT0,1,2 because they can better handle the starting surge current, but you should add the flyback diodes.
-
@Phaedrux @dc42 thank you for your prompt reply. Just going through the above Phaedrux post and the https://forum.duet3d.com/topic/17910/duet-3-6ch-out4-6-out7-9-max-current-question/3 something crossed my mind. The fan outputs4-9 of Duet 3MB 6HC can carry up to 2.5A if the jumper is set on to VIN,
Can I use output4-9 for brushless motors if the motor's current specification less than 2.5A?Another question related to the above figure; the brushless motor current limit 3A, but the current available in out0-2 is 5Amps, would this be a problem for brushless motors because of higher current input?
-
@maddy said in Water pump and air pump setup to Duet 3 Expansion 3HC:
@Phaedrux @dc42 thank you for your prompt reply. Just going through the above Phaedrux post and the https://forum.duet3d.com/topic/17910/duet-3-6ch-out4-6-out7-9-max-current-question/3 something crossed my mind. The fan outputs4-9 of Duet 3MB 6HC can carry up to 2.5A if the jumper is set on to VIN,
Can I use output4-9 for brushless motors if the motor's current specification less than 2.5A?Yes. Outputs 4-9 can handle surge currents greater than 2.5A, but 2.5A is the maximum recommended continuous current because of the 2.54mm connectors.
Another question related to the above figure; the brushless motor current limit 3A, but the current available in out0-2 is 5Amps, would this be a problem for brushless motors because of higher current input?
No.
-
thank you.