Senva CT1O-A3X Outdoor CO2 Sensor, No LCD

The Senva CT1O-A3X is a CT1O outside-air CO2 sensor with an NDIR sensing element, a built-in heater, and no LCD display. No optional temperature output is selected.

CO2 output scaling is 0-2000 ppm by default, with selectable 0-5000 ppm and 0-10000 ppm ranges. Analog outputs are 4-20 mA and selectable 0-5 V/0-10 V. The integrated programmable normally open solid-state setpoint relay is rated 1 A at 30 VAC/DC.

Specified CO2 accuracy is +/- (30 ppm + 3% of reading) at 400-2000 ppm and +/- (50 ppm + 5% of reading) at 2000-5000 ppm, at -10 to 50 degrees C and 0-85% RH. These are accuracy conditions, not an overall operating-temperature rating. Supply requirements are 12-30 VDC, 50 mA maximum, or 24 VAC, 100 mA maximum; 10 V output requires 15-30 VDC or 24 VAC. A dedicated transformer is recommended because one side of the transformer secondary is connected to signal common.

The enclosure is rated NEMA 1. The manufacturer specifies adding drain holes to the enclosure bottom to achieve NEMA 3R; do not assume the unmodified enclosure has that rating.