Fluke 718 Series, Руководство пользователя

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718 Series
Users Manual
8
Switch Test
To perform a switch test, do the following:
Note
This example uses a normally closed switch. The
procedure is the same for an open switch but the
display reads OPEN instead of CLOSE.
1. Connect the Calibrator mA and COM terminals to the
switch using the pressure switch terminals and
connect an external pump between the Calibrator and
the pressure switch. The polarity of the terminals does
not matter.
Note
If using an external pump, connect the pump to
the Calibrator and to the input of the switch using
a tee fitting.
2. Make sure the vent on the pump is open and zero the
Calibrator if necessary. Close the vent after zeroing
the Calibrator.
3. Press
S
to enter pressure switch test mode. The
Calibrator will display CLOSE instead of a mA
measurement.
4. Apply pressure with the pump slowly until the switch
opens.
Note
In the switch test mode, the display update rate is
increased to help capture changing pressure
inputs. Even with the enhanced sample rate,
pressuring the device under test should be done
slowly to ensure accurate readings.
5. OPEN is displayed once the switch is open. Bleed the
pump slowly until the pressure switch closes. RCL
appears on the display.
6. Press
S
to read the pressure values for when the
swith opened, for when it closed, and for the
deadband
Hold
S
for 3 seconds to reset Switch Test mode; hold
any other key for 3 seconds to exit.