Modbus data is processed as data bytes. This data cannot directly process decimal values. Therefore scaling is defined to convert decimal values to a form that can be sent using Modbus, or to correctly interpret values received from Modbus. Data in the Holding register and Input register is scaled according to the formula:
| Actual value = Value in register * 10-Scaling |
For each Modbus address, the scaling is given in the Modbus server tables.
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Scaling example The Modbus address for battery frequency (holding register 0x03, 46342) has a scaling of 2. When the frequency is read from the controller using Modbus, the Modbus register returns 5000. The actual frequency is:
To write a new frequency of 60.00 Hz using Modbus, the value to write to the register is:
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