Sensor Field Calibration

There are two connectors in each crate.

1 power (4 pin female)

1 signal (7 pin male)

For the power connector, pin 1 is closed, 2 is common, 3 is hot and there is a ground.

For the signal connector, 1 is positive and 2 is negative. It sends out a 4..20 mA isolated signal.

The probes should NOT be in the process without power on them.

Power units up for 2 days to stabilize.

Then you need to calibrate to ambient conditions. Take Cover off electronics – Leave open for 30 minutes

Download Conversion Spreadsheet,

To do the calibration, all you need to do is enter in the ambient temperature and relative humidity of the ambient air in cells D2 and D3 of the “Standard” worksheet of the attached spreadsheet. J3 will be the corresponding % volume value.

Divide the value of J3 by % volume range of sensor and then multiply by 16. The range on the milliamp output is 16 amps (4..20mA). Add 4 to that value and that is the corresponding mA value of ambient air. Adjust the offset potentiometer until you get that value. CW raises the milliamps. Page 6 in the manual shows where the offset potentiometer is located.

Set up a 4..20mA connector with the 2 wires exposed so you can attach a multi-meter. The multi-meter needs to be set to mA DC. Unhook the signal output on the housing which is going to the DCS and put this connector on. This way you can do the adjustment right at that meter and not have to have the DCS involved.

Once finished, reconnect the DCS output line.