Product Description:

B & R Automation designs the X20AT2222 temperature input module as part of its X20 Fieldbus Input Output Modules series. The unit converts resistance changes from connected platinum sensors into digital temperature data that a controller can process. By digitizing RTD inputs at the module level, it supports stable thermal feedback without requiring separate signal conversion hardware. This makes it suited for closed-loop temperature control tasks on production lines and process skids.

It accepts 2 channels, and each channel uses a resistance measurement method, so the circuitry reads the sensor’s ohmic value rather than a millivolt or milliamp signal. Both channels support Pt100 and Pt1000 RTDs, allowing the use of standard or higher-sensitivity sensing elements without a different module type. A resolution of 0.1 °C provides precise temperature feedback, and the module sends this as an absolute value for straightforward comparison in PLC logic. The dual-channel layout also places two sensing points in one slot, which helps reduce card count in distributed control panels. This arrangement is useful when two related process points must be monitored within the same I/O slice.

For reliable service in control cabinets, the module tolerates ambient temperatures from -25 to 60 °C horizontally and -25 to 50 °C vertically, so mounting orientation does not create unusually tight cooling limits. Measurement accuracy is maintained up to 2000 m elevation and in atmospheres with up to 95% non-condensing humidity. To reduce electromagnetic interference on the low-level RTD leads, shielded wiring is required, and the spring-cage push-in terminals accept two ferruled conductors up to 0.75 mm² per channel. That conductor capacity supports daisy-chained sensor grounds while keeping lead resistance low for accurate temperature calculation. When sensor cables run near high-frequency power electronics, a continuous shield path helps limit induced noise on the resistance leads.