Fluke 718 Series, Руководство пользователя

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Pressure Calibrator
Sourcing Loop Voltage
19
Sourcing Loop Voltage
The Calibrator can supply loop power at 24 V dc to a
current transmitter that is disconnected from the system.
Use the following procedure:
1. With power off, hold down
U
while pressing
O
on. The “Loop Power” icon appears in the display.
2. With the transmitter disconnected from normal loop
power, connect the Calibrator mA (+) and COM (-)
test leads in series with the instrument current loop as
shown in Figure 7.
3. Measure loop current in the mA display.
4. Press
O
off to deactivate the 24 V dc supply when
you are done sourcing loop voltage.
In addition to mA, the current can be displayed in two
alternative modes:
•
Percent Mode- The current is displayed as a
percentage based on a 4-20 mA scale.
•
Percent Error Mode- Transmitter current output error
is displayed. Error is calculated based on a
configurable zero and span pressure and a 4-20 mA
scale.
1. Measure loop current in the mA measurement display.
2. Press
O
OFF to deactivate the 24 V dc supply when
you are done sourcing loop voltage.
Percent Error Setup
Press and hold
a
. After 3 seconds the set icon and 0%
appears on the lower display. Use
W
and
X
to adjust the
0% point for the Percent Error calculation, then press
D
(ENTER) key to confirm selection. Press
a
. 100%
is displayed on the lower display. Use
W
and
X
to adjust
the 100% point for the Percent Error calculation. Press
D
(ENTER)
to confirm the selection and to exit.
S I G N A L
T E S T
+
–
qo007f.eps
Figure 7. Sourcing Loop Voltage