The HP20 from OptoTherm Inc., Sewickley, PA, provides temperature control of thermoelectric modules and heating/cooling stages within a –40°C to 250°C temperature range. The device operates in a bidirectional, H-bridge configuration for smooth transitions between heating and cooling cycles and provides output current of up to 20 A at 12 VDC and ±0.01°C accuracy. PID capabilities enable rapid response to changes in operating conditions and provide tight control over a broad temperature range. PC-based TE View software lets you configure and operate the controller via the controller's RS-232 interface. Once configured, you can disconnect the computer and operate the controller manually.