ELSA 3L-SP - Chapter 4 Communication Protocol: Modbus Parameters of 3 L-Sp;Ap

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CHAPTER 4 COMMUNICATION PROTOCOL: MODBUS PARAMETERS OF 3L-SP/AP
Serial port configuration: 9600 B, 8 data bits, 1 stop bit, no parity.
Communication protocol: MODBUS, functions 3 or 4.
Slave (control panel) #: Set-up in a configuration menu on panel.
Maximum no. of words to read per request: 35, 32 recommended to avoid unnecessary loading of
communication lines.
Modbus register address for 3L-SP/AP panel:
Zone 1 [Type of alarm]
Modbus address
(Function 3)
Physical
address (Hex)
Remark
Zone 1 [cable length (Hex)]
40001
0001h
Address value in hex and unit = meter
Zone 1 [cable break (Hex)]
40002
0002h
0 - cable OK,
65535 (decimal)- cable break
Zone 1 [1
st
leak alarm (Hex)]
40003
0003h
1
st
leak alarm
0 - no leak
65535 (decimal) - leak alarm
Zone 1 [2
nd
leak alarm (Hex)]
40004
0004h
2
st
leak alarm
0 - no leak
65535 (decimal) – leak alarm
Zone 1 [1
st
leak location (Hex)]
40005
0005h
Address value in hex and unit = meter
Zone 1 [2
nd
leak location (Hex)]
40006
0006h
Address value in hex and unit = meter
 The RS485 polarisation shall be ensured by the supervising station.
 The transmission line shall be terminated by a 120 Ohms/1W resistor at the end of the RS485 link
(the last panel of the link). The shield of the data transmission cable should be connected to the
Supervisor’s panel ground point.