
Table of Contents
4COM461MT_D00011_00_M_XXEN/05.2013
6.2 Modbus requests ........................................................................................... 26
6.3 Modbus responses ........................................................................................ 26
6.4 Structure of the exception code .............................................................. 27
6.5 Modbus address structure for BMS devices ......................................... 27
7. Modbus process image in the memory of the COM461MT ................... 29
7.1 Requesting data ............................................................................................. 29
7.1.1 Modbus function code ................................................................................ 29
7.1.2 How are the memory areas organised? ................................................ 29
7.2 Memory scheme of the process image ................................................. 30
7.2.1 BMS device address assignment on the Modbus .............................. 30
7.2.2 Memory scheme of an individual BMS device .................................... 31
7.2.3 Device name ................................................................................................... 33
7.2.4 Timestamp ....................................................................................................... 34
7.2.5 C = Common alarm and D = Device lost (device failure) ................ 34
7.2.6 Channels 1 to 32 With analogue and/or digital values .................... 35
7.2.6.1 Float = Floating point value of the BMS channels .................... 35
7.2.6.2 A&T = Alarm type and test type (internal/external) ................. 36
7.2.6.3 R&U = Range and unit ......................................................................... 37
7.2.6.4 Channel description ............................................................................. 39
7.2.6.5 Channel 33 to 64 ................................................................................... 40
7.3 Reference data records of the process image ..................................... 41
7.3.1 Address assignment of the reference data record ............................ 41
7.3.2 Reference value on channel 1 ................................................................... 42
7.3.3 Reference value on channel 2 ................................................................... 43
7.3.4 Explanation of how to access floating point values ......................... 43
7.4 Channel descriptions for the process image ....................................... 45
7.5 Modbus control commands ...................................................................... 57
8. Technical data ................................................................................................ 59
8.1 Tabular data .................................................................................................... 59
8.2 Dimension diagram ...................................................................................... 61
8.3 Standards, approvals, certifications ........................................................ 61