York YVAA, Installation, Operation & Maintenance Instructions Manual, Page: 106 / 178

JOHNSON CONTROLS
106
SECTION 7 - OPERATION
FORM 201.28-NM1.1
ISSUE DATE: 1/31/2018
BUILDING AUTOMATION SYSTEM (BAS)
COMMUNICATIONS
There are three different ways the chiller communi-
cates to the BAS.
• Via board Native Communication protocol
• Using an E-Link Gateway
• Using an SC-EQ Communication Card
Using Communications Protocol
TB3 Port 1 Native BAS RS-485.
SW1 RS-485 Biasing Switch for Port. Set to ON if
chiller is in an End of Line position on the network.
U26 is the Port 1 RS-485 Driver Chip. It is
socketed to allow field replacement. RX1 and TX1 LEDs
illuminate to indicate Port 1 communications activity.
YVAA Native Communication Setup
Native communication is applicable to three types of
protocols, they are BACnet, N2 and Modbus RTU.
It requires IPU II Microboard (331-03478-101) and
software version Y.ACS.20.02 or later.
BACnet MS/TP Setup Port 1 (TB3)
To setup the BACNET MS/TP Port 1, follow the
steps below:
1. Connect the BACnet MS/TP Network to Port 1 on
the IPU II I/O Board.
2. Set up the YVAA Port 1 (P1) for BACnet Com-
munications as shown in
Figure 19 on page 105
.
To access the Port communication parameters:
1. Press the PROGRAM key once.
2. Enter password 5255.
3. Press the

(ENTER) key to display the Port 1
(P1) settings.
Set the following parameters:
1. DE Modifier Address (number entered is
multiplied by 100): set as required by network.
2. DE Modifier Offset (number entered is added to
DE Modifier Address): as required by network
(see 8).
3. P1 Protocol: set to BACNET (Default Setting).
4. P1 Manual MAC Address: set to 1
(Default Setting).
5. P1 Baud rate: set as required by network.
If not known set to AUTO.
6. P1 Parity: set to NONE (Default Setting).
7. P1 Stop Bits: set to 1 (Default Setting).
8. The BACnet DE Instance (Device Instance) is
determined by adding the :
[DE MODIFIER AD-DRESS x 100] with the
DE MODIFIER OFFSET .
For example, if the desired DE Instance
address is 5023, set the DE Modifier Address to
50, and then set the DE Modifier Offset to 23
(50 X 100 + 23 = 5023). DE Instances must be
limited to values between 1 and 4,194,303 and
every device in the network must have a unique
Device Instance.
N2 Metasys Setup Port 1 (TB3)
1. Connect the N2 Network to Port 1 on the IPU II
I/O Board as shown in
Figure 19 on page 105
.
2. Set up the YVAA Port 1 (P1) for N2 Communica-
tions.
To access the Communication parameters:
1. Press the PROGRAM key once
2. Enter password 5255
3. Press

(ENTER) to display the Port 1 (P1)
settings.
Set the following parameters:
1. DE Modifier Address: N/A
2. DE Modifier Offset; N/A
3. P1 Protocol : Set to N2
4. P1 Manual MAC Address: Set to 0-127 as
required by the parameters set in the BAS
network.
5. P1 Baud Rate : 9600
6. P1 Parity: None (Default Setting)
7. P1 Stop Bits1: (Default Setting)
Reboot required (cycle power) after
settings are changed.