PD6820 Loop-Powered Process Meter Instruction Manual
39
Advanced Function Selection (
FUNCTN
)
The
Advanced Function
menu is used to select the advanced function to be applied
to the input: linear, square root, programmable exponent, or round horizontal tank
volume calculation. The multi-point linearization is part of the linear function selection.
Meters are set up at the factory for linear function with 2-point linearization. The linear
function provides a display that is linear with respect to the input signal.
Multi-Point Linearization (
lnear
)
Up to 32 linearization points can be selected under the Linear function. The multi-
point linearization can be used to linearize the display for non-linear signals such as
those from level transmitters used to measure volume in odd-shaped tanks or to
convert level to flow using weirs and flumes that require a complex exponent. These
points are established via direct entry (
SCALE
) or with an external calibration signal
(
CAL
).
Manual Entry (
SCALE
)
Manual entry of the linearization data is done once the number of points has been se-
lected (
NO PTS
). Input signal levels (
InP 1-32
) for up to 32 points, along with the de-
sired/corresponding meter reading (
dSP 1-32
) should be entered for each lineariza-
tion point. See Figure 9 on page 40.
External Calibration (
CAL
)
Linearization data can be entered using a known accurate signal source (
InP
1-32
)
and then entering the desired/corresponding meter reading (
disp 1-32
) for that input
signal level. See Figure 9 on page 40.
Important Navigation Note:
After entering the last display value, the linearization entries must be saved
(
SAUE?
) before they will be 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 however, the user must navigate back to
the Save menu screen (
SAUE?
) and press the Enter key to save the changes.
