AMMONIA User Manual
AMMONIA_User 9/09
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Configuration - Operation
Manual - Auto
A 4-20mA output may be switched from Auto control to Manual.
Manual mode allows the user to set an output from 0% to 100% to base feed, set up feed rates and verify
monitoring inputs.
On return to Auto the 4-20mA span and controlling sensor or relay are restored, unchanged.
Hardware Calibration
COM
V
+
-
DVM
DC Volts
Verifying Loop Current
15 VDC
Controller DC Supply
1+ 1- 2+ 2-
Part: IO
Dual 4-20mA
Output
Loop Terminating Resistor,
Typically 249 ohms
1. Insert a mA meter in series with
current loop cabling.
OR
2. Test with loop disconnected
as shown on right
4mA = 1V
20mA = 5V
Hardware Calibration is used to compensate for component level errors.
It’s only available via the keypad and forces the current loop to 20mA to adjust SPAN and to 4mA to adjust ZERO. Trim Zero
default = 9 Trim Span default = 950