Hach Sigma 950, Инструкция по эксплуатации инструмента

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65
Communications Setup
8.3.1.2 Programming the 4–20 mA Output
The dual isolated 4–20 mA current loop outputs on the 950 Flow Meter are unique, they
can be assigned to any of the available channels, not just flow. In addition, the 4 mA and
20 mA current levels are programmed to any desired minimum and maximum value for
that channel.
1. From the Main Menu, select
OPTIONS > ADVANCED OPTIONS > 4–20 mA OUTPUTS >
SELECT
.
2. When the 4–20 mA outputs are disabled and the 950 is not completely turned off,
they will continue to output a steady 4 mA.
3. Press
CHANGE CHOICE
to enable the 4–20 mA outputs. Press
ACCEPT
.
4. Choose
OUTPUT A
or
OUTPUT B
and press
SELECT.
5. Select an Input Channel (channel 1, 2, 3, flow, etc.) to assign to that output. Press
CHANGE CHOICE
to cycle through the channel names. When the desired channel is
displayed, press
ACCEPT
.
6. Assign a channel value to the 4 mA current value. This value is typically 0, however
any value can be set. In other words, enter the value of the input needed to generate
4 mA of current at the output.
7. Assign an input value to the 20 mA current level.
8. Repeat this process to configure the other 4–20 mA output.
8.3.1.3 Calibrating the 4–20 mA Output
After wiring the 4–20 mA connection, perform a 4–20 mA output calibration. The 4–20 mA
output calibration requires a multimeter and an interface or access to the 4–20 mA
current loop wiring. Two 4–20 mA outputs are available and are designated Output A and
Output B. Both outputs are calibrated the same way and are isolated from each other.
11:00 AM 21 - APR - 01 4–20 mA OUTPUTS
SELECT
OUTPUT A
OUTPUT B
RETURN
11:00 AM 21 - APR - 01 4–20 mA OUTPUTS
ACCEPT
CHANGE
CHOICE
INPUT CHANNEL:
CANCEL
FLOW
SELECT APPROPRIATE UNITS
11:00 AM 21 - APR - 01 4–20 mA OUTPUTS
ACCEPT
4 mA INPUT VALUE
CLEAR
ENTRY 0.00 mgd CANCEL
SELECT APPROPRIATE UNITS