P
RO
V
U
™ PD6100 Strain Gauge, Load Cell, and mV Meter
Instruction Manual
39
Auto-Zero (
Auto 0
)
Auto-zero corrects for drift that can occur over time
that causes the input signal to slowly change. The
meter will continue to read zero despite slow and
small changes to the input signal. The auto-zero value
represents the percent of full scale drift that the meter
will correct.
Under normal circumstances, when the signal
increases quickly, by an amount greater than the
auto-zero percent of full scale, the value will not be
adjusted for. Slow signal changes that occur over time
at increments less than the auto-zero value, will not
register on the meter (example: dust on a load cell or
sensor drift over time).
Low-Value Cutoff (
CutofF
)
The low-value cutoff feature allows the meter to be
programmed so that below a certain value, the meter
always displays zero.
The cutoff value may be programmed from 0 to
999999. The meter will display zero below the cutoff
value. Programming the cutoff value to zero disables
the cutoff feature.
Analog Output Programming
(
AoutPr
)
The
Analog Output Programming
menu is used to
program the behavior of the 4-20 mA output. The
following parameters and functions are programmed
in this menu:
1. Source: Source for generating the 4-20 mA
output (e.g. PV)
2. Overrange: Analog output value with display in
overrange condition
3.
Underrange: Analog output value with display in
underrange condition
4. Max: Maximum analog output value allowed
regardless of input
5. Min: Minimum analog output value allowed
regardless of input
6. Calibrate: Calibrate the internal 4-20 mA source
reference used to scale the 4-20 mA output
Analog Output Source
The source for generating the 4-20 mA output may be
assigned to the process variable, maximum or
minimum value reached by the process, one of the
set points, or the Modbus PV input.
Analog Output Calibration
To perform the analog output calibration, it is
recommended to use a milliamp meter with a
resolution of at least 0.1 µA to measure the output
current. The values saved internally during this
procedure are used for scaling the 4-20 mA output in
the
Setup
menu.
Analog Output Calibration
Procedure
1. Wire the PD6100 4-20 mA output to a current
loop that includes a power supply (internal or
external 12 to 24 VDC), and the mA input on the
digital meter. See
2. Turn on all devices. Allow for a 15 to 30 minute
warm-up.
3. Go to the Advanced Features menu, and
navigate to the Analog Output Programming
(
AoutPr
)/Calibration (
Calib
) menu and press
Enter
.
4. The display will show
4 nmA
. The PD6100 mA
output should now be close to 4 mA. Press Enter
and the display will show 04.000. Enter the actual
value read by the digital mA meter and press
Enter
.
5. The display will show
20 nmA
. The PD6100 mA
output should now be close to 20 mA. Press
Enter
and the display will show 20.000. Enter the
actual value read by the digital mA meter and
press
Enter
.
6. The meter will now calculate the calibration
factors and store them.
7. Press
Menu
to exit and return to Run mode.
