I feel like this has been beaten around the bush in a couple other topics, but I am hoping to find something a bit more definitive. I am looking to control a Peltier thermoelectric cooler.
I've got a 24VDC PLC with a couple tools at my disposal:
- Analog thermocouple inputs
- Analog outputs 0-10VDC, 4-20mA, 12 bit
- Digital outputs 500 mA, 24VDC
- PID ladder block in PLC software
I would like to use the PID in conjunction with one of the output types to drive the Peltier at full power (12VDC, 5A). I need some way to convert either of these outputs to a 0-12V controllable constant signal (As pointed out in other threads, the Peltier will wear out if cycled/supplied PWM input).
Some thoughts...
- PWM controlled buck converter (haven't found one, but maybe I'm searching for the wrong things??, everything I have found is trimmer controlled) w/ 12V power supply
- Use RC circuit to change PWM to analog (or analog output) and combine with MOSFET to control a 12V power supply
- DC motor controller to step to required voltage, then RC circuit to smooth
Ideally, I'd love a box that takes 12V 5A in, and a 24V PWM duty cycle dictates the voltage % to an output. It seems like this should exist, but I don't know what to look for.
Also, lest it be too obvious, but unsaid, I am not super experienced with electronics design, nor am I seeking to be an expert. My intention is only to move what I have to move, heat what I have to heat, or in this case, cool what I have to cool. Therefore, I'm not looking to tinker too much, the most direct, robust solution is definitely the best here even if it's not the cheapest.
Thank you all!