Rowland there is a thread running over on CN (DSLR sub-fourm) talking about cooling modules. A recent post there suggested that simply toggling on and off a TEC via power on and off via the PWM, actually decreases the life-span of the TEC. The suggested solution was to install some electronic components, the quote from the thread is here:
"
You can solve this problem electronically with an LC filter. The combination of inductor and capacitor stores energy that covers the "off" states and keeps constant power flowing to the peltier. This is recommended anyway with peltier control, as the instant on/off voltage change with PWM can shorten the life of the peltier if done continuously."
I'd be interested in your take on that comment. While the setpoint controller I am using does switch the PWM on and off, the PWM pot does allow control of the power to adjust it to reduced level to maintain almost steady state operation once you have achieved near setpoint temps. Sure this is a manual setting, and I guess it could be done electronically but I like having manual control over that. What are your views on adding LC filters to 'store' energy for off-states to smooth operation?
CN thread link is here, go to the end to find the post (#353) related to the LC.
http://www.cloudynights.com/topic/51...3#entry6888351