Jumbo Display Process Indicator Controller-AI-04 C by Ace Instruments are state-of-the-art microcontroller based instruments with user inputs selectable between all thermocouples ( J, K, R, S ), Current (4-20mA) & RTD Pt-100 User Selectable : 4-20 mA,RTD Pt-100,J,K,R & S thermocouple. Standard 230 V.A.C., 50 Hz. / Optional 24 VDC. Enclosure - Wall Mountable Powder Coated M.S. Control Output - 2 Relays NO/C/NC rated 230V/6 A from Controller. Optional : RS485 Modbus Protocol Communication. Optional : 4-20 mA Retransmission