Model 1801 Moisture Analyser - Basic

Water vapour in the range 0 - 1,000 ppm can be measures with this analyser using an electrolytic cell.

Water vapour is a notoriously difficult measurement to make as it adheres to stainless steel tubing, valves, filters etc. Diteco use chemically treated tubing to reduce the adherence of the water to the tubing.

Model 1801 Moisture Analyser - Basic
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The operating principle of the moisture analyser is as follows. Sample is passed through a phosphorous pentoxide (P₂O₅) electrolytic cell of proven performance at a constant flow. All of the moisture in the sample is continuously absorbed on to the P₂O₅ and electrolysed by passing a current through the platinum wires. According to Faraday's Law, the moisture content of the gas is proportional to the amount of current required for electrolysis.


The benefits to the user are as follows:

  • Absolute Measurement - Calibration not required
  • Built-In Sample System - Reduces installation costs
  • Simple Cell Regeneration - Low cost of ownership
  • Chemically Treated SS Tubing - Prevents moisture adhering to tubing walls

The DITECO 1801 Moisture Analyser can be utilised in a wide range of applications, in fact on most flowing gases where a fast, accurate measurement of trace water vapour content in a gas is required.

Applications include:

Nuclear Power : CO2 Coolant
Petrochemical : Instrument Air
    Inert Gas Blanketing
Food : O2 and CO2 Packaging Gases
Gas Manufacture : Quality of Permanent Gases
Cryogenics : Purity of CO2, N2, O2, etc.
Medical : Instrument air, NO, O2
Semiconductor : Glove Boxes
Power Generation : H2 alternator gas
Ranges : 0-1,000 / 0-10,000
    ppm(w) ranges also available
Accuracy : ± 3% of range
Response Time : 30 sec for T90
Ambient : 1 ⁰C to 45 ⁰C
Output : 4-20 mA/ 0-30 mV
Alarm : One fully adjustable relay
Power : 100-120, 220-240 VAC     45 to 65 Hz


Pressure : 0.4 to 10 Bar g
Temperature : -10°C to 70° (above sample dewpoint)
Flow Rate : 0.1 to 2 l/min


Fault alarm
Power Fail alarm
Low flow alarm

DIMENSIONS: 365(w) x 192(h) x 360(d) mmWeight 7 kg