Communications Wiring (Bacnet); Bacnet Device Addressing - Carrier WTC-B-207 Installationsanweisungen

7. Communications wiring (BACnet)

WTC-207-B / WTC-307-B
For optimal performance, use 0.5 mm²
stranded, 3-wire shielded cable. The BACnet
MS/TP communication wire is polarity
sensitive and the only acceptable topology is
to daisy-chain the cable from one controller to
the next.
The first or last daisy-chained BACnet
■
MS/TP device must have its EOL resistors
enabled / installed. All other devices must
have their EOL resistor disabled (default
factory setting).
The controller's EOL termination is
■
defined by setting the last two pins,
marked EOL, of the DIP switch located
on the faceplate:
– If both pins are set to "0", the EOL
resistor is disabled.
– If both pins are set to "I", the EOL
resistor is enabled.
For EOL termination on other BACnet
MSTP devices, please refer to the applica-
ble installation instructions.
Isolate all shields with electrical tape so
■
there is no exposed metal that can touch
ground or other conductors.
When the BACnet MS/TP data bus is
■
connected to a following device, twist
data bus shields together.
The shield of the data bus must be
■
connected to the electrical system ground
at only one point – usually at one end of
the bus as shown later in this section.
Connect no more than 50 devices to a
■
BACnet MS/TP data bus when no Light/
Blinds modules are connected. Connect no
more than 30 devices to a BACnet MS/TP
data bus when Light/Blinds modules are
connected.
10
Characteristics
Communication support type RS485
(3 wires + shielding).
Recommended cable type: 3 wires or
2 twisted pairs Belden ref. 9842.
The Belden cables of series 8332, 9829, 8102,
8302 can also be used.
Maximum length: 1220 m.
BACnet Network
To Next Controller
Figure 4: X7 BACnet Communications wiring

BACnet device addressing

Remove one of the stickers from the WTC
faceplate and glue it on the building map for
further commissioning.
The MAC address must be set according to
your network planning document:
By setting the DIP switch located on the
■
faceplate.
When this DIP switch is set to 0 (all
■
OFF), the MAC address can be set by
connecting one of RCI-D/-DC/-DM/-
DCM interfaces to the controller (see
WTC Service Guide).
Figure 5: MAC address setting
(Service settings menu)
X7 on Controller 1
(1) COM
(2) NET-
(3) NET+
X7 on Controller 2
(1) COM
(2) NET-
(3) NET+