EN
OPERATING PRINCIPLE OF PANELS
PEAK POWER VS POWER DURING ACTUAL USE
Peak Power is measured under Standardized test conditions (STC) : Insolation of 1000W/m², cell
temperature at 25°C.
During real use the panel temperature is at 45°C +/- 2% and the maximum insolation strength is of
850W/m²
A panel of 300W peak only produces 200W in reality (see table below)
Panel
(STC norm)
400W
600W
900W
*Temperature correction = 0.4% / degree above 25°C or 8% loss for 45°C (NOCT)
**Insolation correction = see explanation above
SERIES OR PARALLEL CONNEXION
In case of a multi-panel configuration, parallel connexion will ensure an optimum production
especially in shaded areas.
In case of parallel coupling, the panel power adds up.
In case of series coupling, the total power equals to the lowest panel power.
Advantages / Disadvantages
Advantages
Disadvantages
26/55
Real power with
Real power with
corrected
corrected insolation
temperature
(lossof 8%)*
(loss of 25%)**
370W
555W
830W
Serie
Series
Simplified connection
Power decrease if a panel is in the shade
(tree, building, chimney, sail, ...)
Lille
Marseille
Power with
loss due to
if 850W
(2 t o5%)
280W
415W
625W
www.uniteck.fr
Winter
Summer
200W/m²
700W/m²
500W/m²
850W/m²
Charging current
with low battery
wiring
between 10V and
11V
275W
30A
410W
40A
610W
60A
Parallel
Parallel
No power decrease when
panel in the shade.
Use of derivation connectors and
longer cable sections