Blue Sky UCM User Manual
Page 17
Installation and Operation Manual
16
MODBUS OVER TCP
The UCM communicates on port 502. The Slave Address / Unit Identifier only applies if MODBUS/TCP communication is converted back to RS-485 by
an external user supplied TCP to RS-485 converter.
SLAVE ADDRESS / UNIT IDENTIFIER
DIP switches AD0 through AD7 as shown in Figure 4 set the UCM’s RS-485 RTU Slave Address / Unit Identifier within a selectable range of 1-247.
Factory default Slave Address / Unit Identifier is 1 (AD0 - AD7 all OFF).
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RTU address DIP switches AD0 through AD7 are only read when the UCM boots and subsequent changes with power
applied are ignored. Note: Booting the UCM with an address setting greater than 247 is not a valid address will restore all UCM
software settings to As Shipped Factory Defaults.
Actual RTU address setting = 1 + Sum of DIP’s weighting code set to ON
Examples: Address 1 = All Off , Address 5 = AD2 set to ON , Address 16 = AD0, 1, 2 & 3 set to ON
WEIGHTING CODE VALUE IF DIP = ON
AD0
AD1
AD2
AD3
AD4
AD5
AD6
AD7
1 2 4
8
16
32
64
128
ISOLATED RS-485
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WARNING: The RS-485 serial port is electrically isolated from battery negative to eliminate ground loops. Do not exceed ±100V
Peak difference between charge controller battery negative and MODBUS Master common. RS-485 terminal block COM connects
to circuit common on the user side of the isolation barrier. Both sides of the isolation barrier are powered by the UCM.
UCM DIP SWITCH AND JUMPER SETTINGS
FIGURE 4
RS-485 SERIAL COMMUNICATION SETTINGS
Default RS-485 serial communication settings are half duplex, 19.2k baud, 8 data bits, Even Parity and 1 stop bit. To access internal DIP switch selectors
and jumpers shown in Figure 4, remove the UCM cover.
RS-485 BAUD RATE AND PARITY SELECT
DIP SWITCH
FUNCTION
DESCRIPTION
BAUD0
Baud rate select
OFF = 19.2k baud, ON = 9600 baud
PARITY
Odd/Even Parity select
OFF = Even Parity, ON = Odd Parity
BAUD1
Parity Override
OFF = Parity per PARITY DIP switch, On = No Parity & 2 Stop Bits
TABLE 3
These connections for
factory use only. DO NOT
attach jumpers or other
connections.
Jumpers installed on these two jumper plugs configure
RS-485 for Half Duplex operation by connecting signals
A-to-A’ and B-to-B’. Factory default is jumpers installed.
Remove jumpers for Full Duplex operation.
MODBUS Isolated RS485 terminal block. COM
connected to user side of isolation barrier.
MODBUS
Address / Unit Identifier
Force use of TCP/IP
Comm defaults
MODBUS baud rate
& parity
)
DIP switch positions
are only read when
the UCM boots.
Changes following
boot are ignored.