mutiple peltier controller

hi, I have a project to design 8 peltier elements wired up parallel so they could cool a case that has a temperature of 50 celsius to 25
for this project i chose tecs which work with 7 amps and 14 volts
i cant wire them in series
so according to that the tecs may use more voltage and current more than their capacity and start to reduce the output power, what is your suggestion for the circuit?
i think i have to design a driver which can supply approximately 60 amps and 14 volts
do i have to use individual driver for each tec or a single driver is enough?
does the driver has a current control circuit?
what else do i need to control them?
also i am using arduino uno

fatemeh_p:
hi, I have a project to design 8 peltier elements wired up parallel so they could cool a case that has a temperature of 50 celsius to 25
for this project i chose tecs which work with 7 amps and 14 volts
i cant wire them in series
so according to that the tecs may use more voltage and current more than their capacity and start to reduce the output power, what is your suggestion for the circuit?
i think i have to design a driver which can supply approximately 60 amps and 14 volts
do i have to use individual driver for each tec or a single driver is enough?
does the driver has a current control circuit?
what else do i need to control them?
also i am using arduino uno

Are you water cooling the hot side?

Paul

Nice idea to build a kW heater for cooling down a case :wink:

Hi,
Welcome to the forum.

Please read the first post in any forum entitled how to use this forum.
http://forum.arduino.cc/index.php/topic,148850.0.html .

A controller for each device and POWER them in parallel sounds the best.
Monitoring the current though each Peltier would be advisable.

You will also have to monitor the heatsink temperature on each device, if you look at the spec for the Peltiers there are some temperature constraints that need to be looked at.

Fan cooling for the output side of the Peltiers will also be needed.

Thanks... Tom.. :slight_smile:

He will need heat sinks on both sides of each Peltier device. On the cold side to efficiently draw out the container heat. And on the heat side to do something with the heat. That is why I suggested water cooling the heat-side heat sinks. Much more compact that a fan for each heatsink.

Paul

fatemeh_p:
do i have to use individual driver for each tec or a single driver is enough?
does the driver has a current control circuit?
what else do i need to control them?

A single driver on a single PWM pin would only give you 256 level of cooling. You can't easily control all 8 separately since the Arduino UNO only has six PWM (analogWrite()) outputs. I would put the TEC's in parallel pairs and control them as four groups.

The "driver" need not be anything more complicated than a big MOSFET. It turns the 14V on and off. You don't need current control.

If you want precise temperature control, use a PID control loop to control the four PWM outputs.

I'm sure OP forgot the fact that eight of those peltiers need watercooling with a radiator/fan for the size of a small car.
PWM-ing peltiers is a bad idea. Better switch on/off one or more peltiers if needed, with individual mosfets.
Leo..

Wawa:
I'm sure OP forgot the fact that eight of those peltiers need watercooling with a radiator/fan for the size of a small car.
PWM-ing peltiers is a bad idea. Better switch on/off one or more peltiers if needed, with individual mosfets.
Leo..

I wonder how much time the OP has spent on the design of the mounting fixtures? Hope he has access to a bunch of aluminum and a metal shop.

Paul

Perhaps the TO has realized how stupid his idea is, and/or that he can't get the expected help in this forum. The expected solution most probably consists of Peltier elements of Unobtainium, which magically annihilate the heat of the case and all other circuitry around it, eventually concentrate it into tiny drops of plasma which can be used to power the house, car and lightsaber.

Hi,
I like this guy on YouTube, has lots of different tech subjects and a peltier refrigerator was one of them plus a freezer, not easy stuff to do.

Tom... :slight_smile: