61C605 is an 8-channel isolated thermocouple input module belonging to Reliance AutoMax/AutoMate 61C series rack I/O product, specially developed for multi-point thermocouple temperature collection in industrial automatic control systems. Original official production has been discontinued permanently, current available goods mainly include original surplus unused stock and calibrated refurbished products, widely used for spare part replacement and system renovation of legacy metallurgy, chemical, thermal power and papermaking production control cabinets equipped with Reliance DCS5000 control system.

61C is the unified series code of Reliance AutoMate rack-mounted analog and digital I/O modules. Numeral 605 stands for customized specification of 8-channel isolated thermocouple dedicated input board without version suffix letter, consistent with mechanical size and backplane bus definition of all standard 61C series modules for unified rack installation and mixed configuration.

Equipped with 8 fully galvanically isolated independent measuring channels, compatible with mainstream thermocouple types including J,K,T,S,B,E,R via system software configuration. Built-in hardware cold junction compensation circuit adjustable by onboard jumper setting, built-in signal linearization algorithm to convert thermoelectric potential into accurate digital temperature value. Internal A/D conversion rate can be modified through side DIP switch, channel-to-channel isolation withstand voltage reaches 2500VAC between field side and internal bus circuit. Working ambient temperature ranges from -20℃ to +55℃, storage temperature covers -40℃ to +85℃, applicable working humidity 5%~95% non-condensing. Module working power is completely obtained from rack backplane bus without extra external power supply. Full scanning cycle of all 8 channels is adjustable within factory specified range, module supports hardware self-inspection during power-on startup with built-in open-circuit detection function for thermocouple wiring.

Rear panel adopts exclusive gold-plated backplane connector for inserting into standard AutoMax rack slot, realizing digital temperature data uploading and parameter configuration command receiving through proprietary internal backplane bus protocol with rack main CPU. Front panel is fitted with detachable protective barrier terminal base for field thermocouple cable wiring, the barrier can be disassembled to expose calibration voltage input terminals for regular precision correction. One single BOARD OK status LED is reserved on front face to display module power supply and self-check running state, no separate channel fault indicator lamps. No external RS485 or general serial communication port is arranged, all data interaction is finished relying on internal rack backplane bus transmission only. Three reserved side access notches are designed for manual adjustment of internal jumper and DIP switch without module disassembly from rack.

Collect tiny thermoelectric voltage signal generated from field mounted thermocouple sensors, finish cold junction compensation and signal isolation filtering inside hardware circuit, conduct high-precision A/D conversion and built-in thermocouple curve linear calculation to output standard digital temperature data. Cyclically transmit processed temperature values to upper AutoMax main controller via backplane bus in real time. Automatically detect open circuit fault of each thermocouple wiring and send corresponding fault diagnostic codes to control system for alarm prompting. Support unified parameter configuration via host programming software and local hardware DIP switching for A/D sampling rate and slot address definition, can be installed with other 61C series analog input/output modules on same rack to construct multi-type mixed temperature measuring system.

Mainly used for furnace body temperature detection in metallurgical heating furnace, reactor and pipeline multi-point temperature monitoring in chemical industry, boiler flue and hearth temperature collection of thermal power unit, drying cylinder and roller temperature measurement of papermaking production line. It is a common alternative spare part for transformation and maintenance of old DCS5000 distributed control system with centralized multi-point temperature acquisition requirement away from central control room.

Cut off total power of control rack and wait more than 15 minutes for internal capacitor residual electricity discharging before pulling out module or modifying field terminal wiring. Remove front terminal protective barrier periodically to clean terminal dust and fasten loose wiring screws, inspect terminal pins for oxidation and corrosion every half year. When BOARD OK indicator keeps off or abnormal temperature data appears on upper system, first check field thermocouple cable breakage and sensor damage to eliminate external fault before replacing module. Avoid overvoltage surge signal accessing signal terminals to prevent internal amplifier and conversion chip damage, implement full-channel precision calibration once per year for long-term continuous operating modules via reserved calibration terminal on terminal base to guarantee measuring accuracy stability.