12. What is the best way to power and control a TEC?
Thermoelectric coolers require smooth DC current for optimum operation. A ripple factor of less than 10% will result in less than 1% degradation in ∆T.
Voltage or current limiting should be used in order to ensure that Imax for the thermoelectric module is not exceeded. A bipolar power supply is required for those applications requiring both heating and cooling. Pulse width modulation may be used at frequencies above 1 kHz. A linear proportional, PI or PID control can also be used.
Marlow does not recommend an ON/OFF control. While this is the simplest control technique, temperature cycling within the thermoelectric module as power is cycled from full ON to full OFF may result in premature failure.