Metek DREXELBROOK Universal IV Lite, Installation And Operating Instructions Manual

Page: 39 / 110

Configuration & Calibration
33
3.7 Set D/A Trim
D/A Trim is NOT a system calibration! This is a pre
calibrated alignment to precision factory settings and
is rarely in need of change. The procedure is intended
only as a slight "meter" adjustment to a known external
reference.
The Digital to Analog (D/A) Trim adjusts the transmitter mA
(current) output. Since the smart transmitter performs a digital
to analog conversion, there may be a discrepancy in the 4-20 mA
output loop as measured with a reliable external milliampere
meter.
For example: After calibration you observe that the tank is
empty and a hand-held mA meter reads 3.94 mA, while the Real
Time View in the PC Menu shows 4.00 mA. By adjusting the
D/A trim, you may digitally manipulate the output current to
equal 4.00. You may also wish to adjust the high end to 20.00
mA.
To make these adjustments, click on D/A Trim on the PC
software Menu Screen and follow the pop-up window
instructions:
Figure 3-12
Setting D/A Trim Menu Screen "Pop-Ups"