Rishabh RISH LM 1340, Operating Manual, Page: 81 / 106

4. Energy Auto-Ranging On Display :
4.1 Calculating Display energy (Auto-ranging):
In case of energy auto-ranging the energy shown on modbus will be in terms of Overflow count (OF) & main
energy counter (M) based on energy unit/resolution & energy digit reset count (EDRC). So energy on modbus
will have unit set in energy resolution on modbus (ie. Wh or kWh or MWh) & overflow energy counter (OF) on
modbus will increment when main energy counter (M) on modbus will cross the number of digits set in energy
digit reset count (EDRC) register (i.e. 7 or 8 or 9).
Whereas energy shown on display will be Combined energy (ie. Calculated from overflow count (OF) on
modbus & main energy Count (M) on modbus) auto ranged based on the 9 digits available on display to show
energy.
Hence the purpose of this document is to establish a relation between modbus energy counters & display
energy.
Total Energy = OF x 10^(EDRC) + M
Where: OF => Overflow Count on modbus
e.g.
Modbus register for Overflow count (OF):
Wh import Overflow count => 30109 Or 40109
M => Main Energy Counter on modbus
e.g.
Modbus registers for Main energy Count (M):
Wh import => 30111 Or 40111
NOTE :
Refer the interface definition manual of this product for modbus register addresses for energy
parameters.
EDRC => Energy digit reset count set by user from display or modbus
For display setting refer Section 3.2.1.12.
For modbus refer Register 46023.
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