corr_metstemp - temperature measured by a METS (methane sensor)

RBR data loggers support the integration of the METS methane sensor from Franatech. In addition to the raw methane sensing element, this sensor also provides an output representing temperature, for the purpose of compensating the temperature dependence of the methane output. That compensation is described in a later section (see Example 10: corr_metsmeth - Temperature correction of METS methane output); this section describes how temperature is derived from the METS temperature output, which requires its own channel in the logger in order to be monitored.

This is not strictly a 'corrected' output channel, as it has no dependence on any other channel in the logger. However it does make use of the x-group of coefficients, commonly used by corrected channels, to describe the behaviour of the logger electronics, whereas the primary coefficients in the c-group represent the behaviour of the sensor itself; it is useful to keep them in separate groups.

The equation is:

where

The output of the temperature sensor is a voltage V, which is related to the logger's reported voltage ratio R by a simple linear equation, the coefficients of which (x0,x1) are determined by RBR Ltd at the factory. The primary coefficients c0,c1 are provided by Franatech for the linear relation between the voltage V and the temperature output T in °C.

CODE

>> calibration 5 type
<< calibration 5 type = temp06

Confirm the channel type.

CODE

>> calibration 5 datetime = 20171201000000, c0 = -5.65608, c1 = 16.80047

Set the core coefficients for the temperature output.

CODE

>> calibration 5 datetime = 20171201000000, x0 = 6.782656, x1 = -9.257345

Set the secondary coefficients for the voltage conversion.

CODE

>> calibration 5
<< calibration 5 type = temp06, datetime = 20171201000000, c0 = -5.65608, c1 = 16.80047, x0 = 6.782656, x1 = -9.257345

Request confirmation of all calibration coefficients.