Model 120HD Portable Hydrogen Analyzer

Model 120HD Portable Hydrogen Analyzer

The 120HD analyzer functions as a katharometer. It operates by having two parallel tubes both of which contain gas and heating coils. The gases are examined by comparing the rate of loss of heat from the heating coils into the gas. The coils are arranged in a bridge circuit so that resistance changes due to unequal cooling can be measured.

One channel contains moisture-saturated air and the mixture to be tested is passed through the other channel. Hydrogen has a much higher thermal conductivity than air and so the Model 120 HD is very sensitive to hydrogen, but it will also respond to any gas whose thermal conductivity is different from that of air.

  • Specifications +


    Operating Principle   Katharometer
    Operating Range  0 to 25% hydrogen in water-saturated air
    Accuracy   ±4% full scale (±1% H2 v/v)
    Response Time   < 1 minute for 90% step change 
    Repeatability   ±2% full scale (±0.5% H2 v/v)
    Environment  Ambient Temperature: 50ºF to 100ºF (10ºC to 38ºC)
    Relative Humidity   0% to 100%
    Shock Test  MIL-S-901D (Navy) Grade B
    Recommended Sample
    Gas Flow Rate
     50 ml/min
    Sample Pressure  5 psi (34 kPa) gauge maximum
    Power Supply  (1) 6V Industrial Alkaline Lantern Battery
    Battery Life (approx.)  120 hours minimum with backlight
    Power Drain  210 mA, 6V (with backlight)
     170 mA, 6V (without backlight)
    Weight  Less than 15 lb with battery
  • Documents +