pwm controlled waterpump

OwenD

@cosmowave said in pwm controlled waterpump:

Has your pump also a pwm control input?

Yes it does.
Essentially I treat it as a thermostatically controlled fan.
Same with the radiator fan.
In my case the radiator fan doesn't ever turn off completely as it has a minimum possible PWM (didn't realise till I got it).

EDIT
I should note that the indicated speed is the impeller speed.
If a hose blew, it would still show as running. I need to put a flow sensor on the return near the radiator as well.

cosmowave

@dc42 said in pwm controlled waterpump:

However, as it draws about 1.7A, you can't power it from the internal 12V supply

Is it possible to power the pump from the bed heater output?
I use a SSR (3-32VDC in) for my bed.
Is it possible to set the bed heater output constantly on, without linking to a temp sensor?

Phaedrux

@cosmowave said in pwm controlled waterpump:

Is it possible to set the bed heater output constantly on, without linking to a temp sensor?

You can invert the pin name with a ! to have it on by default.

cosmowave

@Phaedrux
oh yes. That's easy!
Thanks

cosmowave

@phaedrux said in pwm controlled waterpump:

You can invert the pin name with a ! to have it on by default.

But is it possible to create the (bed) heater, which i'd like to use for powering my water pump (always on), without linking it to a temp sensor?
With M950, the T parameter seems not to be optional...

Phaedrux

Well you can link it to any temp sensor you like with any temp range you like. So in effect any sensor could allow it to be enabled or disabled.

I suppose you could define it as a GPIO pin to control the water pump with an M42 command instead of as a heater, then it's just on or off.

o_lampe

@cosmowave
Maybe define it as a spindle? That way you don't need a temp sensor and can set RPM directly. (as percentage of max RPM)

cosmowave

@o_lampe But is "spindle on/off" M3 / M5 not CNC/laser specific ? Can i use the commands in printer mode?

tecno

@cosmowave said in pwm controlled waterpump:

@o_lampe But is "spindle on/off" M3 / M5 not CNC/laser specific ? Can i use the commands in printer mode?

Why do you need to PWM control this cooling unit? I use similar as @OwenD SSR to switch on the pump. Always ON

M950 F1 C"out6" Q500  	; create fan 1 on pin out6 and set its frequency  Hotend Cooling Waterpump
M106 P1 S1

cosmowave

@tecno I'd like the idea to control the speed of the pump... also for reliability.