Product Description:

The 7AT664.70 is an analog temperature input module built by B & R Automation for the System 2003 Controllers series. It interfaces thermocouple sensors with the controller backplane so the PLC can record process temperatures and trigger downstream logic. By converting small millivolt signals into digital words, the module allows closed-loop monitoring of kilns, ovens, or heat-treatment lines inside an industrial installation. This makes the module suitable for applications where gradual thermal changes and alarm thresholds must be tracked directly within the control system.

Its analog-to-digital converter works at a 16-bit resolution, giving 65,536 discrete counts across the measurement range. Basic accuracy is specified as ±(50 µV + 0.001 × UTH) [µV], which limits temperature error introduced by the front end. The card accepts four thermocouple channels, and the sensor assignment is fixed per module, simplifying configuration. There is no channel or PLC isolation, so all inputs share a common reference within the rack, while supply-voltage wiring protection helps prevent damage from misconnected power leads. Converted values are placed on the internal I/O bus in integer form, and the housing carries an IP20 rating that restricts use to clean control cabinets.

During every scan, the module is polled at a constant cycle time, so the control program receives evenly spaced updates without additional ladder tuning. Total power draw is just 0.4 W, allowing dense installation on a shared power segment without exceeding backplane limits. Temperature results are reported as signed INT values that correspond directly to microvolt input, and built-in linearization supports the industry-standard J, K, and S thermocouple families. Because protection circuitry is limited to low-energy wiring faults, external galvanic isolation should be added when sensors are exposed to high common-mode voltages.