Calibration Frequency for XCell Sensors with TruCal without Diffusion Supervision (H2S & CO only)

Sensors with TruCal technology will adjust sensitivity without any manual intervention or calibration, unless called for by the sensor. If the adjusted sensitivity from TruCal deviates too far from the last gas calibration sensitivity, the sensor will recommend or, in extreme cases, require a calibration. When a calibration is recommended, the transmitter LED status indicators slowly pulse green. Users can also enable a Calibration Alert function that will send a milli-amp signal on the analog output to the control room when a calibration is recommended. When a calibration is required, the status LEDs will flash yellow and the transmitter will go into a Calibration Required Fault. Without Diffusion Supervision, regular calibration of the sensor must still be conducted to confirm the sensor inlet is not obstructed.

Actual TruCal sensor performance will depend on the application, background gas exposure, and environment. To validate XCell sensors with TruCal, it is recommended that users follow their regular calibration cycle and record the “as found” and “as left” values, tracking the percent adjustment over time. Once a baseline is established, the calibration intervals can be extended until the percent adjustment is greater than the expected accuracy of the sensor.