KMC Controls
Revision E
Installing the controller
Connecting outputs
10
4–20 mA inputs
To use a 4–20 current loop input, connect a 250 ohm resistor from an input to
ground. The resistor will convert the current input to a voltage which can be read by
the controller analog-to-digital converter. Set the pull-up switch to the
Off
position.
Ground terminals
Input ground terminals are located next to the input terminals. Up to two wires, size
14
–
22 AWG, can be clamped into each ground terminal. If more than two wires must
be joined at a common point, use an external terminal strip to accommodate the
additional wires.
Pulse inputs
Connect pulse inputs under the following conditions:
◆
If the pulse input is a passive input such as switch contacts, then place the
input pull-up in the
On
position.
◆
If the pulse is an active voltage (up to a maximum of +5 volts DC ), then place
the input pull-up jumper in the
Off
position.
Connecting
outputs
The BAC-7302 includes one single-stage triac, two-three stage triacs and one
universal output. All triacs are rated for 24 volt, 1 ampere loads, switch on zero
crossing and are optically isolated.
Caution
When connecting loads to triacs, use only the terminal marked RTN associated
with each triac for the 24-volt ciruit.
Output 1
This output a single triac is designed to switch a 24-volt AC fan motor
starter circuit.
Output 2
Typically programmed with a PID loop object to control two-stage
heating. Triac 2A turns on when the programmed output is above 40% and turns off
below 30%. Triac 2B turns on when the programmed output is above 80% and turns
off below 70%.
Illustration 2-2 Output terminals
OUT4
GND
T3B
RT
N3
T3A
T2B
RTN2
T2A
RT
N1
T1
OUT4
GND
T3B
RTN3
T3A
T2B
RTN2
T2A
RTN1
T1
Universal
output and
ground
Triac 2a and 2b
output and
return
Triac 3a and 3b
output and
return
Triac 1
output and
return