Product Discontinued

RH Systems DP-19 Dew Point Instrument

DP-19 Dew Point Instrument

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The model DP-19 is a robust, easy to carry dew point hygrometer, specially designed for field use.

Typical Application

A typical application of this instrument is the spot measurement in sulphur hexafluoride (SF6). Measurements are made at pressures between 10 mbar and 10 bar (1 kPa to 1 Mpa). Sample gas flow is effected by pressure difference between gas inlet and outlet, with a minimum of 10 mbar (1 kPa). If sample gas pressure is too low or the gas has to be measured in a closed circuit, an optional gas pump is available.

Measurement Principle

The measurement is based on the chilled mirror principle which guarantees direct and precise measurement of the actual humidity with no errors due to inertia and hysteresis. The system is stable and does not require recalibration. A built-in ice test device with simple push button action allows the instrument to be checked for accuracy at 0C.

Standard Version

The standard version of the DP19 instrument includes a front-mounted, pressure-tight measuring head with triple stage Peltier cooling. An important option is the unique ORIS-device for the rapid stabilization of the dew point at very low humidity's (patented). For the measurement of aggressive gases, the whole gas circuit is made of PTFE and stainless steel. A built-in electronic flowmeter, which works independent of position, monitors the correct gas flow. An analog output of 10 mV/C is provided for recording or remote indication. For the transport of the instrument and its accessories, a carrying case is available as an option.

Standard Equipment

The standard equipment for SF6 measurement consists of:

  • Dew Point Instrument
  • Sampling Line (FEP, 3 m), with control value and quick couplings
  • Instruction manuals
  • Transport Case

Other Versions

Other versions for the measurement in compressed air systems or similar installations with filters and special tubing depending on customers requirements are also available.

973 SpecificationsWe reserve the right to change design or technical data without notice.

Measuring Range: -60C max at 10C ambient temperature
-55C max at 20C ambient temperature
-45C max at 35C ambient temperature
Values valid for measurements at atmospheric pressure, at overpressure slightly less.
Accuracy: < 0,2C, 1 digit (standard)
Reproducibility: < 0, 1C, 1 digit
Readout: Digital, 3 digits
Analog Output: 10 mV/C, 0C = 0 mV, mA optional
Measuring Principle: Dew Point Mirror, rhodium plated, optical detection
Cooling: Thermoelectric, Peltier-Battery, 3 stage
Sample Gas Flow Rate: 15 to 60 l/h, norminal 30 to 40 l/h
Sample Gas Pressure: Min. 10 mbar up to 10 bar (1 kPa to 1 Mpa)
Response Time: 2C/sec. max.
Gas Pump: Optional
Mirror check: Manual check by pressing the "MIRROR CHECK" - key
Instrument Check: Manual cooling and precision check by pressing the "TEST COOLING" - key (on mirror check position with open measuring head)
Voltage: 100/ 110/ 127/ 200/ 220/ 240 VAC 10%, 50/ 60 Hz
Power Consumption: approx. 160 watts
Ambient Temperature: -10...+50C for storage and operation
Ambient Humidity: Max. 90% RH, non condensing
Weight: Approx. 12 kgs
Size: 342 (W) x 140 (H) x 326 (D) mm

Options and Accessories

  • Gas Pump
  • "ORIS"-System for accelerated Measurments at low Humidities
  • Various Gas Couplings (e.g. Swagelok/ Dilo/ Walther ect.)
  • Carrying Case