Communications wiring
RTU Open v3
Carrier Proprietary and Confidential
CARRIER CORPORATION ©2016
Integration Guide
All rights reserved
12
Johnson N2
To set up the RTU Open for N2
Refer to
Appendix D
(page 49) for the N2 Protocol Implementation Conformance Statement (PICS).
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, set a unique N2 slave 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 N2 slave addresses are 01-99.
EXAMPLE
To set the N2 slave address to 01, point the arrow on the
MSB
(
SW1
) switch to 0 and the arrow on
the
LSB
(
SW1
) switch to 1.
3
Set the Comm Selector DIP switches
DS1
and
DS2
for the 9600 baud.
NOTE
Use the same baud rate and communication settings for all controllers on the network segment. The
RTU Open is fixed at 9600 baud, 8 data bits, No Parity, and 1 Stop bit.
4
Set
SW3
Comm Selector DIP switches
DS3
through
DS6
for N2. See example below.
5
Leave
DS7
and
DS8
in the OFF position. These switches are not applicable to N2.
SW3 Protocol Switch Settings for N2
DS8
DS7
DS6
DS5
DS4
DS3
Off
Off
Off
Off
On
On
The following example shows the DIP switches set for 9600 baud and N2.
6
Connect the N2 EIA-485 network to the controller's
J19
port. Connect to
Net+
,
Net-
, and
SHLD
.