How to read kWh value from PM200 and PM700 Modbus registers?

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Issue
How to read kWh value from PM200 and PM700 Modbus registers?

Product Line
PM200 and PM700 series

Environment
Reading energy from PM200 and PM700 series meters.

Cause
Customer is not reading correct energy values via modbus register.

Resolution
The complete modbus register list for PM200 and PM700 can be found from Knowledgebase article Series 200 and 700 Power Meter (PM200, PM700, PM750) Register List with 3.050 firmware functionality. .

An example of how to interpret these readings is the following:
- kWh reading is located in registers 4000 & 4001 with hex format (range is from 0 to FFFFFFFF).

Range of each register is from 0 to FFFF only.
So to read the complete value, you have to read the value from those 2 specific registers as well as the register for energy's scale factor.

An example calculation is as follows:
READING Energy Registers:
register 4000 = 0012;
register 4001 = ABCD;
Scale factor - register 4108 (power of 10) = 2

CALCULATION
1. Combined values from 2 registers in hex format as 0012ABCD
2. Then convert 0012ABCD into Decimal which is 1,223,629.
3. Next, multiply the combined value with scale factor which is 1,223,629 * (10^2) = 122,362,900.
4. As a result, 122,362,900 is the actual value energy value.