Model: LC5296-AT /LC5248E-AT/LC5296V-AT
masibus
Doc. Ref. no. : - m61C/om/301
Issue no. 13
User’s Manual
Page 37 of 44
10. COMMUNICATION PROTOCOL–MODBUS RTU
10.1 Introduction
The unit can be connected in RS-485 communication data link either in multi drop or
repeat mode. Each unit must have unique Serial Number. Entire range of addresses (1 to
247) may be used. Before starting any communication, choose a baud rate compatible to
the host computer. The serial protocol used is MODBUS RTU.
Function Code for Modbus
CODE
NAME
Function
01
Read coil status
Use to read Relay and Digital output status
03
Read Holding registers
Use to read PV, Control, RSP output etc
04
Read input registers
Use to read programmable registers
06
Preset Single register
Use to write programmable register
The error checking field contains a 16-bit value implemented as two eight-bit bytes. The
error check value is the result of a Cyclical Redundancy Check (CRC) calculation
performed on the message contents.
10.2 Parameter Address Details
Sr.
No.
Parameters
Absolute
Address
Type
Access Type
1
PROCESS VALUE
30001
Int
Read Only
2
POWER IN PERCENTAGE
30002
Int
Read Only
3
AUTOTUNE STATUS
30003
Int
Read Only
4
AMBIENT
30004
Int
Read Only
5
SSR STATUS
30005
Int
Read Only
6
RELAY-1 STATUS
30006
Int
Read Only
7
RELAY-2 STATUS
30007
Int
Read Only
NOTE:Process Value (PV) Error Conditions Value
OPEN
:
32767
UNDER
:
32765
OVER
:
32766
Sr.
No.
Parameters
Absolute
Address
Type
Access
Type
1
Input Type
40001
Int
R + W
2
Zero
40002
Int
R + W
3
Span
40003
Int
R + W
4
Filter
40004
Int
R + W
5
SET Type-1
40005
Int
R + W
6
Open Sensor Status
40006
Int
R + W
7
Relay Delay -1
40007
Int
R + W
8
Hysteresis 1
40008
Int
R + W
