Description
The pressure probe works with a differential pressure
according to the principle of a strain gauge.
Connecting the probes
The pressure inlets in the differential pressure probe are
marked with + and -. The higher pressure should be
applied to the + inlet to achieve the best possible
accurary level. Higher pressure at the + inlet produces
a positive pressure indication, while higher pressure at
the - inlet produces a negative pressure indication.
Application
Set the connected probe to its position of use before
beginning a measurement. We recommend the use of a
magnetic holding fixutre (see ordering data). Zero calibrati-
on should be carred out before the
measurement in order to guarantee reproducable measu-
rements. The position of the probe should not be altered
during the measurement that follows! Zero calibration is
not necessary for measurements with the absolute pres-
sure probe (0638.1645). The pressure probes are calibra-
ted in the factory, calibration is carried out when the pres-
sure probe is lying flat (normal position). We therefore
recommend that the probe remains in this position during
measurements.
Make sure that the pressure probe is not subject to vibra-
tions during the measurement (vibrations effect the results
of the measurement).
Handling instructions
Pressure probe
0638.1445
(±10 hPa),
0638.1545
(±100 hPa)
0638.1645
(2 bar abs)
Please read before using instrument!
Observe measuring range (max. excessive pressure), too high pressure values can dest-
roy the sensor!
Please read the appropriate instruction manual before using the instrument!
In order to obtain reproducable measurements with differential pressure probes and to
maintain the accuracy ±3Pa with the 10 hPa probe, the following should be observed:
- The probe must be adjusted to the ambient temperature before the start of the
measurement!
- Zero calibration must be carried out before beginning a measurement, the position of
the pressure probe should not be changed during the measurements that follow!
- The pressure probe can be positioned as required.
- Avoid changes in temperature during the measurement!
- O and - inputs!
testo
0638.1445
99 Washington Street
Melrose, MA 02176
Phone
781-665-
1400
Toll Free 1-800-517-8431
