Maxwell DR04C is a din rail mount PID temperature controller, 2 channel configuraitons, works with TC/RTD inputs, and output can be Relay, SSR Drive, or analog like 4-20mA, 0-10VDC, 2 auxiliary outputs can be assigned as the alarm output for any of the channel, or it can also be configured as the cooling output, in some particular application, the auxiliary output can also be programmed as an event output which is controlled by a master device via RS-485 communication, the RS-485 is a standard features. 24VDC source to sure greater saftey.