084B8521
by Danfoss
The 084B8521 programmable controller is produced by Danfoss as part of the MCX Programmable Controllers series. It executes embedded logic, accepts field sensor feedback, and energizes connected outputs inside industrial automation panels. By integrating digital processing with onboard I/O, it manages temperature loops, small machinery functions, or auxiliary building services without relying on an external PLC. Its compact form factor, electrical ratings, and communication interfaces allow it to be mounted directly in distributed cabinets or equipment housings. This capability simplifies wiring and shortens commissioning time in OEM equipment.
Power is supplied at 230 V AC, allowing the controller to connect directly to single-phase mains without step-down hardware. It maintains timing accuracy across different utility grids because its input stage accepts 50/60 Hz line frequency. Two relay channels give the unit 2 outputs for actuating contactors, solenoid valves, or visual alarms, while an analog front end offers 2 temperature sensor inputs suited for closed-loop regulation. These inputs can be wired to thermistors or resistance elements, and the firmware automatically linearizes signals from NTC-M2020, PTC 1000, and Pt 1000 probes.
Field connectivity is achieved through MODBUS and LON networks, letting the unit exchange setpoints or alarms with supervisory systems. Local interaction is enabled by a built-in display that shows process values and permits parameter editing without external tools. The hardware contains no batteries, so configuration data is stored in non-volatile memory and there are no periodic cell replacements. A net mass of 0.202 kg keeps panel loading low, supporting DIN-rail installation alongside breakers, contactors, and terminal blocks.
