Fronius TS 5kA-3, Руководство по эксплуатации

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must be greater than the sum total of the power of the Fronius Smart Meter TS
and the leads. The higher the power, the better.
Line resistances at different cross-sections (copper wires)
Secondary cur-
rent
[A]
Cross-section
[mm²]
Line resistances at different lead lengths
(outgoing and return lead)
0.5 m 1.0 m 2.5 m 5 m 10 m
5 1.5 0.3 VA 0.6 VA 1.5 VA 2.9 VA 5.8 VA
5 2.5 0.2 VA 0.4
VA
0.9 VA 1.8 VA 3.6 VA
5 4 - - 0.6 VA 1.1 VA 2.2 VA
Example
The length of the outgoing and return lead (0.5 m each) between the Fronius
Smart Meter TS and the current transformer is a total of 1 m and has a copper
cable cross-section of 1.5 mm²; the line resistance is therefore 0.6 VA according
to the table above. The self-consumption of the Fronius Smart Meter TS is 0.5
VA.
Line resistance 0.6 VA + self-consumption 0.5 VA = 1.1 VA
→ A current transformer with a rating of 1.5 VA, 5 VA or higher is suitable here.
Accuracy class
Use Class 1 or better (Class 0.5 / 0.2, etc.). Class 1 is equivalent to a deviation of
± 1% of the secondary current at maximum power.
Mounting
Rigid or hinged
"Rigid" is usually cheaper with better power and accuracy values. Hinged current
transformers can be opened for attachment to the conductor. To prevent it being
opened inadvertently, a plastic cable tie can be secured to the current trans-
former. Hinged current transformers can be installed in a system without inter-
rupting the voltage.
Connecting the
current trans-
formers
1
Make sure that the current transformers match the voltage phases. Make
sure that current transformer L1 measures the current on the same phase
that is monitored by voltage input L1. The same applies for phases L2 and L3.
2
Make sure that the current transformers are pointing in the correct direction.
Observe the data sheet for the current transformer.
3
Note down the nominal current of the current transformer for each meter.
These values will be required for setup.
4
Attach the current transformers to the conductor to be measured and con-
nect the cables of the current transformer to the Fronius Smart Meter TS.
IMPORTANT!
Always switch off the power supply before disconnecting live conductors.
5
The current transformers are connected to connections 4 and 5; 6 and 7; 8
and 9. If necessary, excessively long cables can be shortened accordingly.
Observe the sequence in which the phases are connected. Accurate power
measurement is only ensured if the mains voltage phases match the current
phases.
Suitable voltage
transformers
Only voltage transformers with a voltage range from 220 to 480 V (phase -
phase) and from 100 to 277 V (phase - neutral conductor) may be used. The
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