25
24
To enter the Modbus address, press the words
Modbus Address
from
Building Automation
menu and
enter Modbus address and
ACCEPT
.
To select, press the words
Modbus Data Type
from Building Automation menu and enter desired data type
and
ACCEPT.
To select Modbus baud rate, press the words
Modbus Baud Rate
from
Building Automation
menu.
Select desired Modbus Baud Rate by
UP
or
DOWN
arrows and
ACCEPT.
To enter the modbus parity, press the words
Modbus Parity
from Building Automation menu and select
desired modbus parity by
UP
or
DOWN
and
ACCEPT.
Communication Protocol
Modbus over RS485
Physical Layer
RS485 Two-Wire plus Signal Ground
Baud Rate
2400, 9600, 19200, 57.6k, 115k)
(default 19200 bps)
Recommended Cable
18 AWG Shielded Twisted-Pair (STP)
Transmission Mode
RTU or ACSII (default RTU)
Maximum Cable Length
Without terminating resistors
- 115,000 baud --> 177 m (580 ft)
- 57,600 baud --> 353 m (1,158 ft)
- 19,200 baud --> 1,000 m (3,280 ft)
- 9,600 baud --> 1,000 m (3,280 ft)
- 2,400 baud --> 1,000 m (3,280 ft)
With 2 x 120 Ohm resistors
- 115,000 baud --> 1,000 m (3,280 ft)
- 57,600 baud --> 1,000 m (3,280 ft)
- 19,200 baud --> 1,000 m (3,280 ft)
- 9,600 baud --> 1,000 m (3,280 ft)
- 2,400 baud --> 1,000 m (3,280 ft)
Start Bit
1 Bit
Data Length
8 Bits for RTU Mode
7 Bits for ACSII Mode
Parity
None (2 Stop Bits)
Even (1 Stop Bit)
Odd (1 Stop Bit)
(default Even)
Addressing
1 to 247 (default 1)
Modbus
®
Specifications
DigiTemp
®
Jr. BAS Integration Manual
DigiTemp
®
Jr. BAS Integration Manual
