Gas Sensor

The Importance of the Gas Sensor

The gas sensor in your RSG machine is key to the filling process. Along with the amplifier board, the gas sensor tells the machine how much gas is in the window and when to stop the filling process. Even though our sensors have a limited lifetime, they can last for years if taken care of properly.

FDR has found that most of our customer's problems are a result of poorly maintained snifflers, filling lances, and hoses – not bad sensors. Therefore, we strongly recommend keeping a backup set of these items to use for troubleshooting if your machine is not working properly.

Calibrating your Gas Sensor

If you are unsure how to calibrate your machine, please download the Calibration Instructions for your machine. If you are already familiar with the regular calibration of FDR gas filling machines, please download the Sensor Measurements Worksheet. The worksheet was designed to be used as a log showing the calibration readings of your gas filling machine. Having this worksheet filled out will assist our technicians in evaluating any problems you may have with your machine. It will also help to familiarize yourself with the entire calibration procedure.

Gas Sensor Identification

Over the years, FDR's gas filling machines have used different gas sensors. While the technology behind the gas sensors has never changed, some of the components have become unavailable. When this happens, it is necessary for us to design a new sensor.

Even though the method of calibrating our gas filling machines hasn't changed, there are internal differences between older revision boards and the newest one, the 1.68.01A/K revision. Specifically, certain resistors need to be changed to accommodate the different resistance in the new sensors.

Please refer to the list below to find out which sensor you should be using with your gas filling machine. It is important to note that using the wrong gas sensor with your board revision level will result in improper calibration of your machine. 

 Sensor Lead Color Board Revision Level Sensor Resistance (Ohms)
Orange (no resistors)  Rev. 1.68.01a 65-85
Rev. 1.68.01k  65-85
Rev. 1.66.01a (ILT) 65-85
Yellow (blue heat shrink) Rev. 1.68  
Yellow (red heat shrink, 1 or 2 resistors) Rev. 1.61-1.64  
Yellow (no resistors) Rev. 1.6  
Green or Black (no resistors) Rev. 1.0-1.5