Chauvin Arnoux pel 102, Руководство пользователя

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79
Distribution
network
Abbreviation
Phase
order
Remarks
Reference
diagram
Three-phase,
3-wire ∆ , balanced
3P-3W ∆ B No
The power measurement is based on the one-wattmeter
method.
The voltage is measured between L1 and L2.
The current is measured on the L3 conductor.
U
23
= U
31
= U
12
.
I
1
= I
2
= I
3
See §
4.1.3.7.
Three-phase
4-wire wye
3P-4WY Yes
The power measurement is based on the three-wattmeter
method with neutral.
The voltage is measured between L1, L2 and L3.
The current is measured on the L1, L2 and L3 conductors.
The neutral current is measured or calculated:
i
N
= i
1
+ i
2
+ i
3
See §
4.1.4.1.
Three-phase,
4-wire, wye,
balanced
3P-4WYB No
The power measurement is based on the one-wattmeter
method.
The voltage is measured between L1 and N.
The current is measured on the L1 conductor.
V
1
= V
2
= V
3
U
23
= U
31
= U
12
= V
1
× √ 3.
I
1
= I
2
= I
3
I
N
= 3 x I
1
See §
4.1.4.2.
Three-phase,
3-wire, wye 2½
3P-4WY2 Yes
This method is called the 2½-element method
The power measurement is based on the three-wattmeter
method with a virtual neutral.
The voltage is measured between L1, L3 and N.
V2 is calculated: v
2
= - v
1
- v
3
, u1
2
= 2v
1
+ v
3
,
u
23
= - v
1
- 2v
3
. V
2
is assumed to be balanced.
The current is measured on the L1, L2 and L3 conductors.
The neutral current is measured or calculated:
i
N
= i
1
+ i
2
+ i
3
See §
4.1.4.3.
Three-phase,
4-wire
∆
3P-4W
∆
No
The power measurement is based on the three-wattmeter
method with neutral, but no power information is available
for the individual phases.
The voltage is measured between L1, L2 and L3.
The current is measured on the L1, L2 and L3 conductors.
The neutral current is measured or calculated for only one
branch of the transformer: i
N
= i
1
+ i
2
+ i
3
See §
4.1.5.1.
Three-phase,
4-wire, open ∆
3P-4WO
See §
4.1.5.2.
DC 2-wire DC-2W No
The voltage is measured between L1 and N.
The current is measured on the L1 conductor.
See §
4.1.6.1.
DC 3-wire DC-3W No
The voltage is measured between L1, L2 and N.
The current is measured on the L1 and L2 conductors.
The negative (return) current is measured or calculated:
i
N
= i
1
+ i
2
See §
4.1.6.2.
DC 4-wire DC-4W No
The voltage is measured between L1, L2, L3 and N.
The current is measured on the L1, L2 and L3 conductors.
The negative (return) current is measured or calculated:
i
N
= i
1
+ i
2
+ i
3 .
See §
4.1.6.3.
Table 27