BAC-7401 Heat Pump Controller
Revision E
Installing the controller
Connecting power
11
Illustration 2-6 shows the position of the BAC-7001 End-of-Line switches associated
with the EIA–485 inputs.
Connecting power
The controllers require an external, 24 volt, AC power source. Use the following
guidelines when choosing and wiring transformers.
◆
Use a KMC Controls Class–2 transformer of the appropriate size to supply
power to the controllers. KMC Controls recommends powering only one
controller from each transformer.
◆
When installing a controller in a system with other controllers, you may power
multiple controllers with a single transformer as long as the total power drawn
from the transformer does not exceed its rating and phasing is correct.
◆
If several controllers are mounted in the same cabinet, you can share a
transformer between them provided the transformer
does not exceed
100 VA
or
other regulatory requirements.
◆
Do not run 24 volt, AC power from within an enclosure to external controllers.
Connect the 24 volt AC power supply to the power terminal block on the lower right
side of the controller near the power jumper. Connect the ground side of the
transformer to the
–
or GND terminal and the
AC phase to the
~
(phase) terminal.
Power is applied to the controller when the transformer is plugged in and the power
jumper is in place.
Illustration 2-6 Location of EOL switch
T4 R
TN T3
T2 R
TN T1
S
EOL switches
Network
disconnect
switch
Off On
Connected
Disconnected
Network
connector
Illustration 2-7 Power terminal and jumper
T4 R
TN T3
T2 R
TN T1
