Input signal conditioning module DSCA37B-07

for thermocouplesisolatedDIN rail

Each DSCA37 non-linearized thermocouple input module provides a single channel of thermocouple input which is filtered, isolated, amplified, and converted to a high-level voltage output. Signal filtering is accomplished with a five-pole filter which provides 85dB of normal-mode rejection at 60Hz and 80dB at 50Hz. An anti-aliasing pole is located on the field side of the isolation barrier, and the other four poles are on the system side. After the initial field-side filtering, the input signal is chopped by a proprietary chopper circuit. Isolation is provided by transformer coupling, again using a proprietary technique to suppress transmission of common mode spikes or surges. The DSCA37 can interface to eight industry standard thermocouple types: J, K, T, E, R, S, B and N. Each module has cold junction compensation to correct for parasitic thermocouples formed by the thermocouple wire and input screw terminals on the module. Upscale open thermocouple detection is provided by internal circuitry. Downscale indication can be implemented by installing a 47 MOhm, ±20% resistor between screw terminals 6 and 8 on the input terminal block.