PD6600 Series Loop-Powered Process Meters
Instruction Manual
7
Input Signal Conditioning
Functions (
FUNCTION
)
The
Function
menu is used to select the input signal
conditioner applied to the input: linear, square root,
programmable exponent, or round horizontal tank vol-
ume calculation. 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.
Square Root Linearization (
SQROOT
)
The square root function can be used to linearize the
signal from a differential pressure transmitter and dis-
play flow rate in engineering units.
PD6602 Displaying Flow Rate by Applying the Square
Root Function to the Output of a DP Transmitter.
Programmable Exponent
Linearization (
EXPONENT
)
The programmable exponent can be used to linearize
the signal from level transmitters in open-channel flow
applications using weirs and flumes.
The PD6602, in combination with an ultrasonic level
transmitter, makes for an economical way to measure
and display open channel flow rate in most weirs and
flumes. A guide such as the ISCO Open Channel
Flow Measurement Handbook can provide the user
with all the information needed: the exponent used in
the flow equation for the desired flow units and the
flow rate for any given head height. For example, to
display the open channel flow rate from a 3" Parshall
flume, the ISCO handbook advises the exponent is
1.547 and at the maximum head height of 3.0 feet,
the flow rate is 3.508 MGD.
Round Horizontal Tank Linearization
(
RH TANK
)
This function automatically calculates the volume in a
round horizontal tank with flat ends. It is only available
for PV2 while the meter is in dual-scale mode.
Set the display for the desired decimal point and engi-
neering units before entering the round horizontal
tank function. Select units (inches or cm) for the tank
dimensions. Enter the diameter and the length in
inches or cm and the results will be calculated auto-
matically in US gallons or liters. The unit of measure
for the volume can be changed using the display
menu.
PD6604 Displaying Height in Feet and Volume in
Gallons in a Round Horizontal Tank Using
the RHT Linearization Feature.
