JOHNSON CONTROLS
110
SECTION 7 - OPERATION
Form 201.28-NM1.1
Issue date: 08/06/2021
MODBUS (RTU) setup port 2
The YVAA 03478 microboard supports Modbus RS232
or RS485 communications for Port 2 communications.
Port 2 communications can be directed to either TB1
for RS232 or TB2 for RS485.
To connect to the network:
1. Connect your Modbus Network to Port 2 on
the IPU II I/O Board as shown in
Figure 18 on
page 105
.
2. Set up the YVAA Port 2 (P2) for Modbus
Communications.
To access the communication parameters:
1. Press the PROGRAM key once.
2. Enter the password 5255.
3. Press the
(ENTER) key to display the Port 1
(P1) settings.
Set the following parameters:
1.
DE Modifier Address: Set to 1
2.
DE Modifier Offset: Set to 0
3. P1 Protocol: Set to API
4. P2 Protocol: Set to Modbus Server
5. P2 Manual MAC Address: Set to 0-127
(as required by Modbus network)
6. P2 Baud rate: Set to 19.2K (or as required by the
Modbus network)
7. P2 Parity: Set to NONE (or as required by
Modbus network)
8. P2 Stop Bits: Set to 1
9. P2 Hw Select Bit: Set to RS-485 or RS-232
( as required by Modbus network)
Cycle power to the Microboard following port setups.
J13-5
Remote Stop Start must be closed for BAS
remote commands to take effect. If this input is open
the unit will shut down and the panel will display the
message:
REMOTE STOP - NO RUN PERMISSIVE.
E-Link or SC-EQ interface
Communications to a LON network requires a LON
E-Link and Port 2 set for YorkTalk 2. Connected
Services requires a SC-EQ and Port 2 set for YorkTalk
2. To connect to the network:
1. Connect the E-Link or SC-EQ to Port 2 on the
IPU II I/O Board as shown in
Figure 18 on page
105
.
2. Set up the YVAA Port 2 (P2) for YorkTalk 2
Communications.
To access the communication parameters:
1. Press the PROGRAM key once.
2. Enter the password 5255.
3. Press the
(ENTER) key to display the Port 1
(P1) settings.
Set the following parameters:
1.
DE Modifier Address: Set to -1
2. Chiller ID: 0
Reboot required (cycle power) after
settings are changed.
