15 P
SID
/G
PRE
SSU
RE M
ODU
LE
700P
04
1 ba
r
100
kPa
RAN
GE
Figure 1.
Avoiding Overpressure Damage
Applying pressure in excess of the burst pressure specified
on the pressure modules can destroy the pressure modules.
W
Caution
Exceeding the maximum rated pressure
may affect total uncertainty. If you
suspect the module has been over
pressured, use the performance test to
check it.
Avoiding Corrosion Damage
To avoid corrosion damage, use only with specified media as
shown below:
•
Isolated: any medium that is compatible with type 316
stainless steel.
•
Non-Isolated: dry, non-corrosive gasses only.
•
700P29Ex: use only with a medium that is compatible
with Hastelloy C276 and type 316 Stainless Steel.
Recommended Measurement Technique
For best results, the modules should be pressurized to full
scale and then vented to zero pressure (atmosphere) prior to
zeroing and making measurements.
Zeroing Gage and Differential Modules
1.
Connect the pressure module to the intrinsically safe
calibrator and select the measure pressure function.
2.
Position the module in the same orientation for which it
will be used.
3.
Vent both high and low side measurement ports to
atmosphere.
4.
Press the [ZERO] key.
Zeroing Absolute Modules
1.
Connect the pressure module to the intrinsically safe
calibrator and select the measure pressure function.
2.
Apply a vacuum to achieve a pressure below the rated
resolution of the pressure module being zeroed.
3.
Press the [ZERO] key, and enter 0.0 as the applied
pressure.
Alternative procedure if a local precision barometer is
available. Do not use the weather service or airport reports.
1.
Connect the pressure module to the intrinsically safe
calibrator and select the measure pressure function.
2.
Press the [ZERO] key.
3.
Enter the value from the precision barometer.
Note
Low range pressure modules may be sensitive to
gravity. For best results, pressure modules 30 psi
and below should be held at the same physical
orientation from the time they are zeroed until the
measurement is complete.
Pressure Calibration Kit
The Fluke-700PCK Pressure Calibration Kit makes it
possible to calibrate pressure modules at ambient
temperature with a precision pressure calibrator better than
the module specification. A PC running Windows
®
software is
required. The kit is an optional accessory available from your
distributor or Fluke.
Performance Test
If you need to check that the pressure module meets its total
uncertainty specification, use a dead weight tester or suitable
pressure calibrator. Proceed as follows to verify that a
pressure module is operating within specification:
1.
Read the pressure value with no externally applied
pressure to make sure the 0% of scale is correct. When
reading the pressure, press the [ZERO] key to remove
any zero offset.
2.
Connect the pressure module to a precision pressure
source.
3.
Zero as described earlier in the appropriate “Zeroing”
sections.
4.
Set the precision pressure source to 20% of the
pressure module’s maximum rated pressure.
5.
Make sure the reading agrees with precision pressure
source value within the total uncertainty specification in
Table 2.
6.
Set the precision pressure source to 40, 60, 80, and
100%. Then reverse the order from 100, 80, 60, 40, and
20% of maximum rated pressure. Repeat step 5 at each
test point.
7.
If temperature sensitivity is of concern, repeat steps 1
through 5 at various controlled temperatures.
Cleaning
W
Caution
•
Measuring substances that
leave residue in the sensor
may cause permanent
damage to the Pressure
Module.
•
Periodically wipe the Pressure
Module with a damp cloth and
mild detergent. Do not use
abrasives or solvents to clean
the Pressure Module.