Toshiba Carrier BMS-IFBN1281U-UL Service Manual page 98

BN interface
Problem
The status of an indoor unit
acquired by BACnet
communication differs from
the remote control display.
When operation of an indoor
unit is performed from a
central monitoring system, a
different indoor unit goes into
operation state.
LED Status
LED-L1 is unlit
LED-L1 is lit
LED-L1 is blinking (during
normal operation), and
LED-LINK(Uh) is unlit
LED-L1 is blinking (during
normal operation),
LED-LINK(Uh) is blinking
(during normal operation)
98 -EN
Cause
When the BN interface and air conditioning
management controller are not being used
together, the "LINK(Uh)" LED of the BN
interface is not blinking.
The central control address, Line address,
or unit address of indoor units has been
changed after a test run of the BN interface.
When the BN interface and air conditioning
management controller were being used
together, the power for the air conditioning
management controller was turned OFF.
NOTE
When used in combination with the air
conditioning management controller, the
"LINK(Uh)" LED of the BN interface does not
blink.
A TU2C-LINK non-compatible Central
Remote Controller and BN interface are
being used together.
The central control address, Line address,
or unit address of indoor units has been
changed after a test run of the BN interface.
Cause
The BN interface internal software has
stopped due to:
• Shutdown
• Disconnection
• Other malfunction
The BN interface internal software has
stopped due to:
• Other malfunction
The BN interface cannot send a Uh Line
communication command to indoor units.
The BN interface internal software has
stopped due to:
• Other malfunction
Action
Confirm whether power is being supplied to the
indoor and outdoor units.
NOTE
When only the VRF indoor unit or outdoor unit
has power supplied to it, because the
initialization of VRF has not been completed,
the BN interface stops communication.
Check the central control address, Line
address, and unit address of indoor units
If the central control address, Line address, or
unit address of any indoor units has been
changed, perform the procedure of "9 Test run".
Turn ON the power for the air conditioning
management controller.
Because the Central Remote Controller
Communicates with the indoor unit every 4
minutes, updating of the indoor unit status on
BN interface is every 4 minutes.
Check the central control address, Line
address, and unit address of indoor units
If the central control address, Line address, or
unit address of any indoor units has been
changed, perform the procedure of "9 Test run".
Action
Reset the BN interface power.
After shutting down BN interface, reset the
power.
Check that the indoor units and outdoor units
are turned on.
Check if VRF System is initializing.
Check that the communication wiring is not
broken.
After shutting down BN interface, reset the
power.
Service Manual