Vaisala GMP 252 CO~2~ probe



Fits inside a 1 inch Schedule 40 PVC pipe, but in order to fint a membrane the thinner-walled 1 inch class 200 will be preferable.

Membrane materials:

* Tyvek 1443R - light (1.25oz/yd), thin (5.3mil), strong, water resistant, pretty easy to work with.
* Gore-Tex socks - source?

Datalogger programming

Sensors can output data in several configurations, both analog (voltage and current) and digital (Modbus).

Single ended voltage measurement

With probes configured for analog output at 0-5V, a single ended or differential voltage measurement can be used to measure the probe. In Campbell dataloggers the relevant commands are SeVolt

Temperature, pressure, and other compensations

Temperature compensation can be performed by