Manual pump control

I have the 24v PWM controlled pump and I use it for recirculation during mashing and wort transfer during my brew day. It’s hooked up to a fixed 5v control voltage and an on/off switch. I would very much like to be able to control pump speed, preferably using a manually operated knob or similar. Could you please advise on how to achieve this?

I have a spark 3 used for fermentation temp control and I think I understand how to make it control the pump, but I don’t want to use a web UI to switch the pump on and off while mashing. Can I hook up an analog knob to the spark for input?

Some suggestions or pointers would be much appreciated.

I’m not aware of any currently supported slider / knob inputs for the Spark.

LED strips commonly come in 24V with dimmers. You could use the 5V as global on/off, and use a 24V knob for physical control.

(Do check electrical compatibility before implementation. This is based on me installing LED strips, not me combining them with pumps.)

This is incorrect @Bob_Steers.

The PWM pump has internal speed control, you should not try to regulate it through its 24V power supply. It should get a pwm signal for the speed.

The Spark doesn’t support analogue input. You could give the pump just digital signal for on/off at full speed and perhaps use a valve to pinch off the output a bit.
Or let the spark send a speed control signal that you can interrupt with a switch.

I have it nicely wired to my mash/boil controller using a 3-wire XLR plug so it gets the 24v power and a 5v control signal that I can toggle with a small switch. Doing the same thing using the spark wouldn’t make much sense. I guess restricting the flow using a ball valve would be pretty simple. Thanks!

I did actually hook it up to a cheap PWM fan controller I got off some website, but that didn’t work at all.

You can have the manual switch and digital speed control.
If the spark sends the speed signal, your switch can override it (interrupt it) to turn the pump off.

I have something similar for my heating elements, they turn on if all of these are true:

  • the spark digital pin is ON
  • a manual switch on the panel is ON (to turn it off regardless of software signal)
  • the float switch is ON (to protect against dry fire)

Wired as follows:
Spark signal + --> manual switch --> float switch --> SSR +
Spark signal - --> SSR -

1 Like