Toshiba Carrier BMS-IFBN1281U-UL Service Manual page 84

BN interface
When connecting to a previous model light commercial, air to air heat exchanger, air to water
heat pump, or general purpose equipment control interface
Follow the wiring specifications in the table below even when there is a mix of U series and non-U series in the connected indoor
units or remote controllers.
Wiring specifications
Item
Wire diameter
Wire type
Wire types that can be used
REQUIREMENT
When wiring the control wiring between indoor and outdoor units (Uv line)/control wiring between outdoor units (Uc line) and the
central control wiring (Uh line), use the same wire type and diameter for each line.
Using a mixture of different wire types and diameters may cause a communication error.
System diagram
BN interface
Outdoor unit
and Other
Indoor unit
Hydro unit
Remote
controller
84 -EN
LINK (Uh)
Light Commercial
U3 U4
U 4
U1 U2 U5 U6
U 2
TCC-LINK
U1 U2
U 4 U 4
adapter
Uv
A B
U 6
Communication line
Central control wiring (Uh line)
AWG16: Up to 3281 ft (1000 m)
AWG14: Up to 6560 ft (2000 m)
2-core, non-polar
Shielded wire
[Central control wiring (Uh line)]
L1 = Up to 6560 ft (2000 m)
[Control wiring between indoor and outdoor units
(Uv line)/Control wiring between outdoor units (Uc line)]
L2 = Up to 3281 ft (1000 m)
Air to Water
Heat Pump
Uh
4
U 4
A B A B
U 6 U 6
Service Manual
U3 U4 U3 U4
General purpose
Air to air heat
equipment
exchanger
control
interface