Siemens SITRANS SL - Enron Modbus

Interfaces to automation systems
8.2 Modbus interface
SITRANS SL
Operating Instructions, 12/2010, A5E01132948-04
143
8.2.4.2 Enron Modbus
This section describes the Enron Modbus register group numbers for the SITRANS SL gas
analyzer.
Register numbers are used to identify specific data items to be read or written. Registers are
grouped by data type.
The following table depicts SITRANS SL Enron Modbus register group numbers.
Table 8- 7 Register groups
Register Type Description
3000 INTEGER 16 Bit integers
5000 LONG 32 Bit integers
7000 FLOAT 32 Bit IEEE floating point
Note
Offset
As default, for all Enron Modbus registers the offset between the register number and the
data addresses is 1. For example, register number 7001 has data address 1B59 (7001 in
decimal).
There is an optional support for an offset 0.
Modbus addresses 3000 ... 3999
Short Integer registers
Short Integer registers are read using function code 03 or set using function code 16.
Table 8- 8 Short Integer registers
Enron
Modbus
address
Access Data Address Description
3001 read 3000 Device Status
3002 read 3001 Component 1 – Concentration
Quality
3003 read 3002 Component 1 – Concentration
Time stamp – Day
3004 read 3003 Component 1 – Concentration
Time stamp – Hour
3005 read 3004 Component 1 – Concentration
Time stamp – Minute
3006 read 3005 Component 1 – Concentration
Time stamp – Second
3007 read 3006 Component 2 – Transmission
Quality