PAGE 11
2.3.6 4-20 mA Output Wiring
If utilizing the 4-20 mA retransmission outputs, they can be wired as shown below.
NOTE: These inputs are non-isolated and cannot be wired with one leg grounded as
in some programmable controllers designed for single ended inputs.
NOTE: If interface boards are to be removed to facilitate wiring, turn power off
before pulling boards. Be careful to align boards properly, with adjust-
ment "pots" to the left.
FIGURE 9 4-20mA OUTPUT CONNECTIONSFIGURE 9 4-20mA OUTPUT CONNECTIONS
FIGURE 9 4-20mA OUTPUT CONNECTIONSFIGURE 9 4-20mA OUTPUT CONNECTIONS
FIGURE 9 4-20mA OUTPUT CONNECTIONS
Section 3 OPERATION
3.1 PRINCIPLES OF OPERATION3.1 PRINCIPLES OF OPERATION
3.1 PRINCIPLES OF OPERATION3.1 PRINCIPLES OF OPERATION
3.1 PRINCIPLES OF OPERATION
Four wire, millivolt sanitary pressure transducers are typically used to sense pressure at raw
product inlet and pasteurized product outlet of the regenerator. These signals are amplified
to a proportional 0-1 volt input by the interface cards within the unit. These interface cards
also develop the 10 volt excitation for the sensors. The proportional 0-1 volt signals reach
the upper display board via the ribbon connector where the Analog-to-Digital converters
condition the signal actuating the displays.
The 0-1 volt inputs are also fed to a computer circuit on the display board which in turn
actuates the differential bar graph. A second comparator compares this value to the setpoint
and actuates the Booster Pump switch contact (K-1).
An optional third comparator on the pasteurized product channel actuates the high pressure
limit switch (K-2).
Additional output circuitry on the lower "power" board provides two-wire, 4-20 mA transmitter
outputs proportional to either input, or the differential. Only two (2) of the three (3) outputs
are available in any unit.
To Next Page
Loading...