Page 64
ST 800 Series HART/DE Option User’s Manual
Revision 5.0
1.
Start the MC Toolkit application such that the DE MAIN MENU is displayed.
2.
Select the
Calibration
button to display the CALIBRATION menu.
3.
Select
Trim DAC Curr.
To display the TRIM DAC CURRENT box.
4.
Trim output current as follows:
a.
Select
Set Output To 0%
or
100%
. You will be prompted to confirm that you want
to place the Transmitter in output mode.
b.
Verify that the loop is in manual control. In output mode, output current is fixed at
the 0% or 100% level as selected in the TRIM DAC CURRENT box in the previous
step.
c.
Select
Yes
, and observe the loop current level. A meter reading of 4 mA corresponds
to 1 volt.
d.
Use the Toolkit to adjust the loop current to the Zero Percent level (4mA). If the
current is low, tap the
Increment
button; if the current is high, tap the
Decrement
button. Note that the value on the meter changes accordingly. If the error is large,
accelerate the adjustment rate by changing the Step Size to 10 or 100.
e.
After establishing the zero current level (4 mA), select
Set Output To 100%
. A
meter reading of 20 mA corresponds to 5 volts.
