Communications wiring
RTU Open v5
CARRIER CORPORATION ©2019
Integration Guide
All rights reserved
5
38.4 kbps
Off
On
76.8 kbps
(Default)
On
On
BACnet MS/TP
To set up the RTU Open for BACnet MS/TP
Refer to
Appendix B
(page 55) for the Protocol Implementation Conformance Statement, or download the latest
from
BACnet International
http://www.bacnetinternational.net/catalog/index.php?m=28
NOTE
This controller counts as a full load on the MS/TP bus.
1
Turn
off
the RTU Open's power.
NOTE
Changes made to the switches when the controller is on will not take effect until the power is cycled!
2
Using the rotary switches
MSB
(
SW1
) and
LSB
(
SW2
), set a unique BACnet MS/TP MAC address for the RTU
Open. Set the
MSB
(
SW1
) switch to the tens digit of the address, and set the
LSB
(
SW2
) switch to the ones
digit. Valid addresses are 01-99.
NOTE
The rotary switches also determine the BACnet device instance of the controller on the BACnet
network. The BACnet device instance is automatically generated based on the scheme 16101xx, where “16”
is the BACnet vendor ID for Carrier Corporation, and xx equals the rotary switch address.
EXAMPLE
To set the controller’s MS/TP MAC address to 01, point the arrow on the
MSB
(
SW1
) switch to 0
and the arrow on the
LSB
(
SW2
) switch to 1. Internally, the BACnet device instance is automatically
generated as 1610101.
10's
1's
1
3
45
2
7
8
9
6
0
1
3
45
2
7
8
9
6
0
SW1
SW2
M SB
LSB
3
Set the
SW3
DIP switches
1
and
2
for the appropriate communications speed (9600, 19.2k, 38.4k, or 76.8k
bps).
NOTE
Use the same baud rate and communication settings for all controllers on the network segment. The
RTU Open is fixed at 8 data bits, No Parity, and 1 Stop bit for this protocol's communications.
Baud DIP switch settings
Baud rate
2
1
9,600 bps
Off
Off
19.2 kbps
On
Off
38.4 kbps
Off
On
76.8 kbps
On
On
