METREL Energy Master MI 2883, Instruction Manual

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MI 2883 Energy Master Theory and internal operation
131
100
 
tot
N
fund
tot
Se
Se
HP
[%]
where:
fund fund fund
Ie Ue Se
tot
  
3
Load unbalance


tot
fund
S
Su
LU
(38)
5.1.6 Energy
Standard compliance: IEC 62053-21 Class 1S, IEC 62053-23 Class 2
Energy measurement is divided in two sections: ACTIVE energy based on active power
measurement and REACTIVE energy, based on fundamental reactive power
measurement. Each of them has two energy counters for consumed and generated
energy.
Calculations are shown below:
Active energy:
Consumed:


 

m
i
p p
i T i P Ep
1
) ( ) (
[kWh], p: 1,2,3, tot
Generated:


 

m
i
p p
i T i P Ep
1
) ( ) (
[kWh], p: 1,2,3, tot
(39)
Reactive energy:
Consumed:
 
 
 

 
m
i
pCap
m
i
Iind p
i T i Q i T i Q Eq
1 1
) ( ) ( ) ( ) (
[kvarh], p: 1,2,3, tot
Generated:
 
 
 

 
m
i
pInd
m
i
pCap p
i T i Q i T i Q Eq
1 1
) ( ) ( ) ( ) (
[kvarh], p: 1,2,3, tot
(40)