Precision Digital Corporation PD8-6262, Инструкция по эксплуатации

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PD8-6262 Explosion-Proof Dual Analog Input Flow Rate/Totalizer
Instruction Manual
58
Analog Output Programming
(
AoutPr
)
The Analog Output Programming menu is used to
program the behavior of the 4-20 mA output. The
following parameters and functions are programmed
in this menu:
1. Source: Source for generating the 4-20 mA
output
2. Overrange: Analog output value with display in
overrange condition
3. Underrange: Analog output value with display in
underrange condition
4. Break: Analog output value when loop break is
detected
5. Max: Maximum analog output value allowed
regardless of input
6. Min: Minimum analog output value allowed
regardless of input
Analog Output Source
The analog output source can be based on either of
the input channel rate, total, or grand totals (Ch-A,
Ch-B), the math channel (Ch-C), maximum stored
value of either input channel (Hi-A, Hi-B), minimum
stored value of either input channel (Lo-A, Lo-B),
relay set points, or the Modbus input.
To base an analog output on the rate, total, or grand
total of channels A or B, select the channel in the
Analog Output Source menu. Then select the rate,
total, or grand total as the source reference for the
output, and program the output scale.
Analog Output Value for Loss of
4-20 mA Input (Loop Break)
The AoutPr - Break menu is used to force the analog
output to go to a user-specified mA value if a break
condition is detected in the 4-20 mA input loop.
Selecting Ignore causes the mA output to go to the
minimum value.
Analog Output Calibration
To perform the analog output calibration, it’s
recommended to use a milliamp totalizer with a
resolution of at least 0.1 µA to measure the output
current. The values saved internally during this
procedure are used for scaling the 4-20 mA output in
the
Setup menu.
Analog Output Calibration
Procedure
1. Wire the PD8-6262 4-20 mA output to a current
loop that includes a power supply (internal or
external 12 to 24 VDC), and the mA input on the
digital totalizer. See
Figure 18. 4-20 mA Output
Connections on page 27 for details.
2. Turn on all devices. Allow for a 15 to 30 minute
warm-up.
3. Go to the Advanced Features menu, navigate to
Select (
Select
) and choose Analog Output
Programming (
AoutPr
)/Calibration (
Calib
) menu
and press Enter .
4. The display will show
4 nmA
. The PD8-6262 mA
output should now be close to 4 mA. Press Enter
and the display will show 04.000. Enter the actual
value read by the digital mA totalizer and press
Enter .
5. The display will show
20 nmA
. The PD8-6262 mA
output should now be close to 20 mA. Press
Enter and the display will show 20.000. Enter the
actual value read by the digital mA totalizer and
press
Enter .
6. The totalizer will now calculate the calibration
factors and store them.
7. Press Menu to exit and return to Run mode.