Sierra Monitor Corporation 4105 manual Appendix C Combustible Gas Scaling Factors Table

Page 18

Instruction Manual

Appendix C: Combustible Gas Scaling Factors (Table 1)

Where possible, calibration gas should be the same as the gas to be detected. If this is not possible then a scaling factor should be used to determine the “equivalent value” of the calibration gas in terms of the gas to be detected. (Note: Concentration of calibration gas must be less than the factor number listed on Table 1).

The formula for calibration is as follows:

Display = (Cal gas) / Factor

where: Display = the span gas applied

Cal gas is the percent methane used for calibration.

Factor is a number that corresponds to the gas to be measured. (see Table 1)

Example: The application is for measurement of Propane and Methane is the calibration gas.

The factor for Propane (from Table 1) is 55.

For the example, calibration gas is Methane at 40% LEL.

Display = 40% LEL Methane / 55 = 0.73

Display = Adjust span until LCD reads 73.

Model 4105 Gas Sensor Module (12/02)

Page: 15

Image 18
Contents Model 4105 Series Applicability & Effectivity Table of Contents Section Product Description Recommended Wire/Cable Gauge Introduction WiringWire Gauge Maximum Length Preventative MaintenanceQuick Start Operation Transmitter Cover Plate Model 4105 Gas Sensor Module 12/02Calibration Service 4a. Combustibles 4b LEL Sensor Fault Supervision4d Missing Electromechanical Sensor Fault Supervision 4c Electrochemical Oxygen and ToxicsPower Supply InstallationExplosion Proof Installation Sensor LocationsOxygen Wiring Diagram Model 4105 Gas Sensor Module 12/02 CombustibleToxics Specifications Range Resolution Response Time Sensor Type UnitsHCN Replacement Parts LimitedwarrantyAppendix a Unity Gain Mode Appendix B L.C.D. Readout Calibration ProcedureAppendix C End of Sensor Life Indication Appendix C Combustible Gas Scaling Factors Table Combustible GAS Scaling Factors Factor