Analog Output - Hoffer Flow Controls CAT2 User Manual

Installation
3.4.

Analog Output

CAT2 provides an Analog Output option that will output an analog
current or voltage that is proportional to the flow rate. The Analog
Output for CAT2 requires an optional circuit board, PCA181.
Analog Output
-
POWER
SUPPLY
-
LOAD
The input frequency is scaled using SW2 on PCA180 so that the
preamp output frequency at max flow is between 75 and 150 Hz. For
example, if the max flow input signal is 1,000 Hz, SW2-4 should be in
the ON position to divide the preamp signal by 8 so that the max
frequency out of the preamp is 125 Hz. Refer to the table in the
previous section for the appropriate switch settings. If the Pulse Output
option is used in conjunction with the Analog Output, the Pulse Output
frequency will be limited by this scaling factor.
There are 3 potentiometers on PCA181 for ZERO and SPAN
adjustment. The ZERO pot adjusts the no flow output, while
COURSE SPAN and FINE SPAN adjusts the max flow output. All
pots are labeled accordingly on the circuit board and may be accessed
by removing the top plate from CAT2. The 0-20mA, 0-5V and 0-10V
options require no ZERO adjustment. Contact the factory for detailed
calibration instructions before making any adjustments.
Analog Output Response Time: The analog output response time to
reach steady state due to a change in the flow rate is approximately two
(2) seconds.
14
DC
+
+
DC+
DC-
SIG+
SIG-
ANLG
PULSE+
PULSE-
N/C
N/C
N/C
HP-311