Hach Sigma 950, Инструкция по эксплуатации инструмента

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Communications Setup
Calibration may be performed while the 4–20 mA device is in the current loop, as shown
in
Figure 15 or disconnected from the current loop as shown in Figure 16 . In either case,
the multimeter must be set to a 20 milliamp dc range or greater.
1. From the Main Menu, select
OPTIONS > ADVANCED OPTIONS > CALIBRATION > 4–20
mA OUTPUTS.
2. Connect a multimeter to the 4–20 mA current outputs per Figure 15 or Figure 16 .
3. Make sure that the 4–20 mA output is enabled. If it is not enabled, press
CHANGE
CHOICE
so that the display shows Enabled and press
ACCEPT
.
4. Select the output (A or B) to calibrate.
5. Press any key to set the selected output to 4.00 mA dc.
6. Measure the current on the selected output using the multimeter and enter the
measured value using the numeric keypad. Press
ACCEPT
.
7. Press any key to set the output to 20.00 mA dc.
8. Measure the current on the selected output using the multimeter and enter the
measured value using the numeric keypad. Press
ACCEPT
to complete the
calibration.
By entering the measured current values, the microprocessor will electronically adjust the
outputs to compensate for the difference between the measured values and the expected
values.
Figure 15 Calibration with the Meter in the Loop
Figure 16 Calibration with the 4–20 mA Device Disconnected from the Loop