How we grab the Kwh value from registers 1700 to 1703, what is significance of the Mod10 format for this register.

Mod10 means the value is splited into 4 registers with a Mod10,000 format.

Each register with range between 0 and 9,999.

Result of the whole value is equal to (R4*10,000^3 + R3*10,000^2 + R2*10,000 + R1). Thus the range of
this result would become 0 to 9,999,999,999,999.

E.g. for Real Energy In, corresponding registers are 1700 to 1703 if the value of these register is as follows:

1700: 4567

1701: 0123

1702: 0000

1703: 0000

Then the actual value would be 1,234,567 Wh