Possible improvements on this circuit with 11 relays to control water pumps, LEDs, motors

Other Hardware Motors, Mechanics, Power and CNC
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My project includes 2 water pumps, 2 led lights, and 4 dc motors. All are turned on and off by relays.
I find that its possible to control motor in both directions using 2 relays.
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I would appreciate some insights if this circuit will work. Is the distribution of power correct? Or did I overlook something?

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I'd suggest to use SSR instead of mechanical relays, and a H-bridge as motor driver.

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Your circuit is fine but note it dynamically brakes the motor when you turn it off. Relays are OK for low duty but if there are cycles per minute best follow DrDiettrich's recommendation and use solid state relay or H-Bridge with MOSFET outputs.

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appreciate all the replies! one more thing. is it ok to power my sensors with 5v? it says that esp is not 5v tolerant

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Look at their data sheets.

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  • All inductive loads require some kind of kickback protection, eg: diode

  • Using 0V to a relay contact like that will soon weld the contact.

  • The ESP32 might not be able to drive the relay card inputs properly.

  • Using 5v to the relay card is not going to give proper biasing for a 0-3.3v output GPIO.

  • Read this discussion to confirm the ESP pins used will work.

No.

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It depends.
The Fritzy drawing shows DS18B20 sensors ( I think). They must be powered with 3.3volt and pulled up to 3.3volt when used with a 3.3volt-logic MCU (the ESP32).

The soil moisture sensors seem to be this one. They should be powered with 5volt, because they have an LDO and their output voltage is 0-3volt.

None of the inductive loads have a back-emf diode. A must if you want stable operation.
Leo..

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i should use 3.3v for vcc of relay instead of 5v?

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