AMMONIA User Manual
AMMONIA_User 9/09
4
5
4.2 4-20mA Configuration
To view or modify the sensor controlling the
4-20mA output current, key
UP
or
DOWN
to the target 4-20mA output and press
ENTER
.
Key
UP
and
ENTER
@
Configure
.
We’re presently in
Manual
mode.
Key
ENTER
to
Return to Auto
and then
UP
to
Control by:
Key
ENTER
to modify
Control by:
Key
UP
or
DOWN
to scroll through
all enabled sensors.
Key
ENTER
to select or
EXIT
to leave unchanged.
In this example we selected NH3
to control the 4-20mA loop current.
Configure
Setpoints
4-20mAOutput_D
4.00mA 0.0%
D
and
Return to Auto
Yes
Control by:
No Control
Control by:
NH3
and
and
or
Select Sensor
Sidebar:
Control by:
Any enabled sensor of any type ‘A’ to ‘N’ may be used to control the
4-20mA loop current.
Once you’ve selected a controlling sensor, adjust the
4mA Setpoint
and
20mA Setpoint
to reflect the range for a remote DCS monitoring input.
Example:
You are controlling the 4-20mA output current using a pH sensor.
If the 4-20mA current is monitored by a building automation system or
distributed control system, you could set 4mA= 6.0pH and 20mA = 10.0pH.
since this span represents the likely range of measured pH.