Process Calibration Tools Catalog 2016-2017

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PROCESSMETER 789
%STEP COARSE FINE SpanCheck
mA
mA
mA
mA
mV
V
V
A
OUTPUT
LOOPPOWER
250
HART
OFF
mA
SOURCEOUTPUT 0-24mASIMULATE
A COM V
MINMAX 100%
0%
HOLD
REL Hz
RANGE
Hand
Pump
Pressure
Gauge
Pressure Input
When you use a Fluke 754
or 3130 to automate the
pressure switch calibration,
vary the applied pressure
slowly, back and forth across
the setpoint and reset points.
The display will make it
apparent that the set/reset
has changed and the actuals
will be logged.
Safely disconnect the device from the process it controls.
Connect the calibrator or DMM to the common and NO (normally open)
output terminals of the switch. The DMM or calibrator will measure an
“open circuit”. if measuring continuity. If measuring V ac be sure the tool is
properly rated for the voltage being measured.
Connect the pressure switch to a pressure source such as a hand pump
connected to a gauge.
Increase the source pressure to the setpoint of the switch until the switch
changes state from open to close. Manually record the pressure value
when the DMM indicates a “short circuit” or if using a calibrator it will
record the value for you.
Continue to increase the pressure until the maximum rated pressure.
Slowly reduce the pressure until the switch changes state again, and
resets from closed to open, then record the pressure.
The setpoint pressure was recorded when the pressure was rising.
The deadband value is the difference between the rising setpoint
pressure and the falling pressure reset point.
STEP
1
STEP
2
STEP
3
STEP
4
STEP
6
To perform the test:
Setup
Rising pressure
Falling pressure
Calculation
Additional resources
For more in depth information about
this application check out these videos
and application notes from Fluke.
See the pressure switch test video at:
Calibrating pressure switches with a DPC
TECH
TIPS
STEP
5
31 Pressure Applications