DO 9704 PRESSURE AND TEMPERATURE DATALOGGER0 pages

DO 9704
MAIN CHARACTERISTICS AND APPLICATIONS
- RECORD function with display of the peak, minimum and mean value.
- Input A-B measurement function for pseudo differential measurements, pressure drops or flow rate with calibrated flanges.
- Relative measurement function with respect to a given instant.
- Zero correction function, especially useful for low pressures.
- Stores up to 30,000 measurements with date and time of measurement and
programmable interval from 1 sec. to 12 hours.
- Double display for simultaneous viewing of the two inputs.
- RS 232C serial output for a printer or for unloading data onto a PC.
Typical applications for this instrument are in the following sectors:
- Hydraulics - Fluidodynamics - Chemical plants and process controls - Compressors
- Pumping plants - Flow rate measurements - Chimney draught - Moulding and
presses for plastics and thermosetting materials - Level measurements
INSTRUMENT TECHNICAL DATA
Inputs/type of measurementt 2 / pressure, flow rate or temperature
Connectort
DIN 45326 8-pole
No. conversions per secondt 2
Working temperaturet
-5...+50°C
Working relative humidityt
0...90% R.H. no condensation
Serial outputt
RS 232C, 300...19200 baud
(galvanically insulated)
Displayt
Double LCD 12.5 mm
Functionst
Auto Power Off, Autorange,
Hold, Record, Peak (5ms), Minimum,
Mean, Relative, A-B (differential)
Memoryt
512kB (FLASH) corr. To 30000 measurements
Power supplyt
9V dc alkaline battery
Autonomyt
Approx. 50 hours (continuous duty)
Weight/dimensions t
20 gr. / 215x73x38 mm
INSTRUMENT ACCURACY
Amb. T.
measures
-5...18 or 25...50°C
Pressure measurements 0.1% FS + 0.1% RDG 0.1% FS + 0.1% RGD
+ 100ppm/°C
RDG = measured value
0.2% FS + 0.5% RDG
Flow rate measurements 0.2% FS + 0.5% RDG
+ 100ppm/°C
0.4°C
0.4°C + 0.01°C/°C
-200...-50°C
Temperatre
0.2°C
0.2°C + 0.01°C/°C
-50...+200°C
measurements
3°C
3°C + 0.01°C/°C
+200...+800°C
DO 9704
PRESSURE AND TEMPERATURE
DATALOGGER
The Delta Ohm DO 9704 pressure gauge and data logger has been designed for
detecting pressure, flow rate and temperature, physical values which are very
important in industrial and chemical processes.
The instrument has two inputs and automatically recognises the probes connected, whether they be pressure or temperature probes or turbines for measuring flow rate.
As the probes are interchangeable, it is possible to choose the most suitable
combination for all applications without having to recalibrate the instrument.
The operating principle of the pressure sensor is based on the deflection of a
membrane in a sealed chamber in contact with the stream you want to measure
the pressure. The flow may be liquid or gas. The flow rate measurement is based
on the number of impulses or the frequency of a small fan. The DO 9704 is able
to measure the following:
Pressure:
- differential or relative pressure from 10 mbar to 2 bar for air or non corrosive
gases;
- absolute and relative pressure from 0.2 bar to 1000 bar for measurements in
contact with liquids or gases.
- The measurement units are: bar, kPa, atm, mmHg, mmH2O and psi.
- The instrument is able to detect peaks of around 5 milliseconds.
Temperature:
interchangeable probes are available with amplified Pt100 elements of the TP
870 series; the measurement can be in °C or °F.
Flow rate:
Flow rate can be measured with a turbine in the range from 2 to 2000 litres
per minute in the measurement units LPM (litres per minute) or IPGM (Imperial
Gallons per Minute).
CLASSIFICATION OF PRESSURE MEASUREMENTS
Pressure measurements are always relative to a reference pressure; there are
four distinguish types that allow you to immediately define the reference pressure.
- Absolute pressure (A=absolute) - Pressure with respect to absolute zero,
ideal vacuum reference; the measured pressure is always higher than the reference pressure.
- Overpressure (G=gauge) - Pressure measured with respect to the atmospheric pressure, environment pressure reference; the measured pressure is
always higher than the reference pressure.
- Depression (V=vacuum) - Pressure with respect to the atmospheric pressure,
environment pressure reference; the measured pressure is always lower than
the reference pressure.
- Differential pressure (D=differential) - Pressure measured with respect to
any reference pressure; the measured pressure may be higher or lower than the
reference pressure.
TP704…
TP705…
Pressure 101
Pressure
Amb. T. 18 to 25°C