Installation Guide

Converting Data to Units of Measurement
975-0691-01-01 Revision B B-61
Converting Data to Units of Measurement
Data from a Modbus register is converted to units of measurement using the
following algorithm:
result = [(data @ Modbus Register) * scale] + offset
Example: Read the Nominal Temperature
The following example shows a conversion of the nominal temperature located at
Modbus Address
0x0400.
Modbus Address = 0x0400
Scale = 0.01
Offset = -273.0
Data type = uint16 (one Modbus register)
units: degree C
Reading one Modbus Register from address
0x0400 yields 0x7440
Apply the offset and scale as follows:
result = (0x7440 * 0.01) + (-273.0)
= (29760
* 0.01) + (-273.0)
= 297.60 + (-273.0)
= 24.60
The conversion yields a nominal temperature of 24.60 degrees Celsius.
Writing Modbus Registers
Modbus does not provide an error response when data written to a Modbus
Register is out of range or invalid. To confirm that a Modbus Register is correctly
written, you should read it back and compare it with the expected value.
Battery Monitor Device Modbus Map
Modbus
Address Name Type Access Units Scale Offset Notes
0x0100 Device Name str16 r
0x010A FGA Number str20 r
0x0114 Firmware Version str15 r
0x011E Hardware Serial Number str20 r
0x0200 Operating Mode uint16 r Enum1
0x0201 Battery Voltage sint32 r V 0.001 0
0x0203 Battery Current sint32 r A 0.001 0
0x0205 Battery Temperature uint16 r degree C 0.01 0