11. Appendix
11.1. DEMAND CALCULATION
Demand parameters are used to show average values over a demand interval.This power meter using sliding
block method. The demand value is based on interval divide by sub-interval time. Example is shown below:
SETTING: Interval time = 180 seconds ; sub-interval = 3
Measurement = interval time / sub-interval = 180 / 3
= 60 seconds
a)
4000-4001
: Negative Real Energy
Negative Real Energy
= 0x00012334
=74548 x 1kWh (min value)
=74548kWh
b)
4012-4013
: Total Real Power; (Signed register)
Total Real Power
= 0xFFFB6C20
If MSB is “1”, it is negative value;
Total Real Power
= 0xFFFB6C20 x (-1);
= 0x493E0; 300 000
= 300000 x 1W(min value)
= -300kW
11.2. DATA READ FORMAT FROM MODBUS
