Hoffer Flow Controls CAT3-DC-MIL User Manual page 22

14 Installation
Analog Output – DC Power
-
POWER
SUPPLY
-
LOAD
1
PCA183
SW1
4–20 mA Output
Analog Output – The Microcontroller, located on PCA183,
accepts the square-wave output of the preamplifier and performs
all of the calculations that are required to control the Loop Driver.
After measuring the frequency of the square-wave, the
Microcontroller uses the following equations to compute the flow
rate and current.
flowrate
Where:
Kfactor = Is dependent on the Flow Calculation Method setting and
FM
CF
HP-324-5
DC
+
+
frequency
=
Kfactor
is either the Average K-Factor or the Linearized K-
Factor from the Frequency / K-Factor table.
= Is the Flow rate Units setting of 0, 1, or 2. Where "0" is
for Seconds, "1" is for Minutes, and "2" is for Hours.
= Is the Correction Factor setting.
DC+
DC-
SIG+
SIG-
ANLG
PULSE+
PULSE-
N/C
N/C
N/C
FM
x 60 xCF