PD6700 Field-Mount Loop-Powered Process Meter
Instruction Manual
17
Multi-Point Scaling (
SCALE
)
The multi-point scaling is entered after selecting the
number of points (
noPtS
). The input signal levels
(
InP 1-32
) for up to 32 points, along with the
corresponding meter reading (
dSP 1-32
) should be
entered for each linearization point.
Multi-Point Calibration (
CAL
)
The meter can be calibrated using a current source
instead of using input scaling. This process will
override previously programmed scaling points.
Apply a live signal using a known accurate signal
source (
InP 1-32
) and then enter the corresponding
meter reading (
disp 1-32
) for that input signal level.
The use of a calibrated signal source is strongly
recommended.
Important Navigation Note
After entering the last display value, the linearization entries
must be saved (
SAUE?
) before they are put into effect.
However
,
you may move past this selection using the Up arrow key if you
need to go back and correct and earlier entry. Once confident in
the entries, you must navigate back to the Save menu screen
(
SAUE?
) and press the Enter key to save the changes.
Square Root Linearization (
Squar
)
The square root function can be used to linearize the
signal from a differential pressure transmitter and
display flow rate in engineering units.
PD6700 Displaying Flow Rate by Extracting Square Root
from DP Transmitter Signal.
Low-Flow Cutoff (
CUTOFF
)
The low-flow cutoff feature allows the meter to be
programmed so that the often-unsteady output from a
differential pressure transmitter, at low flow rates,
always displays zero on the meter. The default cutoff
is zero to prevent negative readings, but this may be
overridden to allow them.
The cutoff value may be programmed from 0 to
99999. Below the cutoff value, the meter will display
zero. Selecting either square root or programmable
exponent will set the cutoff value to 0. Program the
cutoff value to 0 to disable.
