The 820 Controller is a versatile and flexible controller, ideal for both small and larger applications. Its modular design allows it to fit almost any application. The 820 Controller is 2-channel controller that can accept 4-20 mA inputs from Industrial Scientific gas transmitters. Multiple 820 Controllers can be used to build as large of a system as required. The small compact enclosure is ideal for instrumentation racks. Dual, ultra-bright LED displays show the gas readings in real time. Five relays (2 low alarm, 2 high alarm, and 1 fault) are used to control external