Honeywell Midas-M Hydrogen (H2) Sensor, 0-1000 ppm, 2 years

Gas Measured	Hydrogen (H2)
Cartridge Part Number	MMS-G2
Sensor Technology	3 electrode electrochemical cell
Measuring Range	H2	0 ppm to 1000 ppm
Default Alarm 1	125 ppm (rising)
Default Alarm 2	250 ppm (rising)
Accuracy	<±5% of measured value
	Exposure to H2 500 ppm for 5 minutes
Response Time (t62.5)	Typical 41 seconds
Sensor Cartridge Life Expectancy	24 months under typical application conditions
Operating Temperature	0ºC to 40ºC (32ºF to 104ºF)
Effect of Temperature	Zero	<±0.31 ppm/ºC
	Sensitivity	<±1.5% of measured value/ºC
Operating Humidity (continuous)	15% RH to 90% RH
Effect of Humidity	Zero	<±0.1 ppm/% RH
	Sensitivity	<±0.1% of measured value/% RH
Operating Pressure	90 kPa to 110 kPa
Effect of Position	No effect in typical application
Long Term Drift	Zero	No drift
	Sensitivity	<12% of measured value/6 month
Calibration Gas	Hydrogen (250 ppm to 750 ppm, default 500 ppm)
Challenge Gas (Bump Test)	Hydrogen (500 ppm)
Warm Up Time	< 10 minutes
Storage Temperature	5°C to 25°C (41°F to 77°F)

Cross Sensitivities

Each Midas-M sensor is potentially cross sensitive to other gases and this may cause a gas reading when exposed to other gases than those originally designated. The table below presents typical readings that will be observed when a new sensor cartridge is exposed to the cross sensitive gas (or a mixture of gases containing the cross sensitive species).

Gas / Vapor	Chemical Formula	Concentration applied (ppm)	Reading (ppm H2)
Ammonia	NH3	100	0
Arsine	AsH3	0.2	0
Carbon Dioxide	CO2	1000	0
Carbon Monoxide	CO	100	150
Chlorine	Cl2	1	0
Chlorine Dioxide	ClO2	1	0
Hydrogen Cyanide	HCN	20	0
Hydrogen Sulfide	H2S	20	4
Iso Propanol	C3H7OH	1100	Yes
Methane	CH4	1%	0
Nitrogen Dioxide	NO2	10	-40
Ozone	O3	0.25	0
Sulfur Dioxide	SO2	5	0

Midas-M Sensor Cartridge Quick Reference Guide

Midas-M Hydrogen Sensor Specifications