Landis+Gyr E350 Series User Manual page 16

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Summation by single
quantities
Σ |A Lx|
Summation by
Absolute value
|+A| + |–A|
20 kWh
10 kWh
0 kWh
–10 kWh
1st hour
L1 2 kWh
L2 5 kWh
L3 -3 kWh
Sum 4 kWh
Cum sum 4 kWh
Subtraction
|+A| – |–A|


© Landis+Gyr
This method summates the quantity of the individual phases independent
of the energy direction. A connection error – however – has no effect on the
result of measurement.
But if there is a real export in one phase, this method leads to incorrect
measurement results.
With this method the meter adds exported and imported energy. This
method only makes sense if the utility is sure there is no energy export.
This method is available in vectorial and magnitude summation mode.
The absolute magnitude summation can be used as an anti-tampering
measure. Here negative magnitudes of A
magnitudes of A , A
L1
2nd hour 3rd hour
2 kWh 2 kWh
5 kWh -5 kWh
3 kWh -3 kWh
10 kWh 6 kWh
14 kWh 20 kWh
Fig. 1.4 Example absolute value summation active energy (left: combined sum,
vectorial, always positive; right: combined sum, magnitude, always positive
per phase)
With this method the meter subtracts an exported energy from the
imported. It cannot detect a connection error.
Use of vectorial and magnitude mode
ZFF meters must work in vectorial mode – we do not have energy values
for each phase (3 phases and only 2 measurement systems).
For ZMF, most of the customers, use vectorial mode too. Only some
customers use magnitude mode, mainly for tamper prevention .
F-circuit
With F-circuit (Aron connection), only the sums of +R and -R are
calculated.
L1
, A . See example below.
L2 L3
30 kWh
20 kWh
10 kWh
0 kWh
–10 kWh
1st hour
L1
L2
L3 -3 kWh
Sum 10 kWh
Cum sum 10 kWh
D000027979 en t – E350 Series 2, 3-Phase ZxF100Ax/Cx – User Manual
Description of Unit
, A , A are added to the positive
L2 L3
2nd hour 3rd hour
2 kWh 2 kWh
5 kWh 5 kWh
3 kWh
10 kWh 10 kWh
20 kWh 30 kWh
2 kWh
-5 kWh
-3 kWh