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Runtech China Brand review

RT400WM

400 Wp Monocrystalline
ComparePV verdict

Middle of its segment, weak in heat

Rank 13,485 of 14,005
Compare panels Datasheet PDF
Power (Wp)
400
Weak · bottom 24%
Efficiency (%)
20.50
Typical · median 21.30%
Density (Wp/m²)
204.8
Typical · median 212.6
Temp (%/°C)
-0.350
Weak · bottom 23%
Weight (kg)
20.5
Typical · median 22.5 kg
Warranty (yrs)
-
Not published

Runtech RT390-420WM series photovoltaic panels are a precise response to the needs of modern prosumer installations, where an optimal price-to-actual energy performance ratio is key. The use of advanced Half-Cut cell technology allows for a significant reduction in power losses resulting from internal resistance and ensures more stable module operation in conditions of partial roof shading. Thanks to the use of innovative Multi-Busbar (MBB) technology, current flow paths are shorter and more densely distributed, which effectively minimizes the risk of micro-cracks and increases the overall mechanical durability of the cells. This series stands out for its low temperature coefficient, which directly translates into higher yields on hot summer days when standard modules lose efficiency. These products are primarily dedicated to owners of single-family homes and farms seeking high resistance to potential-induced degradation (PID) and long-term reliability in the variable Polish climate. Compared to the competition, Runtech modules offer an optimized frame and tempered glass construction, which guarantees safety under heavy snow loads. Choosing this series is an investment in energy stability, combining modern aesthetics with solid materials engineering, representing a substantive alternative to more expensive premium segment solutions.

Ranking

6,519 panels in the 300-500 W band, all technologies
Metric This panel Median Position in segment Overall rank
Module efficiency 20.50% 21.30% Typical 11,308
Power density 204.8 212.6 Typical 11,370
Temperature coefficient -0.350 -0.300 Weak · bottom 23% 10,419
Weight per kWp 51.2 53.2 Typical 4,641
Performance warranty - 30 yrs Not published 13,880
Colour key Strong - top 25% Typical - middle 50% Weak - bottom 25%

Signals from the data

0 positive · 1 caution
Best for

Residential, shaded-installations and hot-climate.

Not ideal for

Hot climates.

Watch-outs
-0.350 %/°C temperature coefficient

Bottom 23% of the 300-500 W band, against a median of -0.300.

Notes from the database
  • Efficiency of 20.5% is 1.3pp below the database median (21.8%)
  • Power density of 204.8 W/m² is 13.3 W/m² below database median (218.1 W/m²) - needs more roof space
  • At -0.35%/°C, loses 0.05pp more power per degree than database median (-0.30%/°C)
  • At 20.5 kg, this panel is 6.0 kg lighter than database median (26.5 kg) - easier handling during installation
  • #11308 for efficiency, #10419 for temperature performance out of 14005 panels

Specifications

Open datasheet PDF
Nominal power (Pmax) 400 Wp Nameplate at 1000 W/m², 25 °C
Module efficiency 20.50 % Typical Segment median 21.30%
Vmpp · Impp 31.01 V · 12.90 A Operating point at max power
Voc · Isc 37.07 V · 13.79 A Sizes the string length
Max system voltage 1500 V Longer strings than 1000 V modules
Dimensions 1722×1134×30 mm · 1.95 m² of roof
Weight 20.5 kg Typical Typical · median 22.5 kg
Cells 108 Monocrystalline
Coefficient Pmax -0.350 %/°C Weak bottom 23% of its segment
Coefficient Voc · Isc -0.275 · 0.045 %/°C
NOCT 45 °C At 800 W/m², 20 °C ambient

Simulations

Live - change any input
Lifetime output & value
30 years at 1200 kWh/kWp/year and €0.50 per kWh
Power in year 30
-
Lifetime energy
-
Energy value
-

Degradation from this panel's own datasheet figures. No inverter, soiling or shading losses.

Heat losses
-0.350 %/°C against a segment median of -0.300
-
Filter these
Size
Panel Power Eff. Temp. Weight Difference
Runtech China RT400WM 400 W 20.50% -0.350 20.5 kg You are here
LX-440M/182-108+GG 440 W 23.07% -0.240 23.6 kg +40 W, cooler, +2.6 pp
JST-EDMH-(445-465)W-TD (450W class) 450 W 23.05% -0.300 20.5 kg +50 W, cooler, +2.6 pp
QNN182-HG450-54 450 W 23.04% -0.290 24.0 kg +50 W, cooler, +2.5 pp
HY440-N108BDD 450 W 23.04% -0.300 23.5 kg +50 W, cooler, +2.5 pp
NLBK-27-450 450 W 23.04% -0.300 22.9 kg +50 W, cooler, +2.5 pp
RS41-450NBG-E3 450 W 23.04% -0.290 24.5 kg +50 W, cooler, +2.5 pp
RT390WM 390 W 20.00% -0.350 20.5 kg -10 W, -0.5 pp
RT395WM 395 W 20.20% -0.350 20.5 kg -0.3 pp
RT405WM 405 W 20.80% -0.350 20.5 kg +0.3 pp
RT410WM 410 W 21.00% -0.350 20.5 kg +10 W, +0.5 pp
RT415WM 415 W 21.30% -0.350 20.5 kg +15 W, +0.8 pp
RT420WM 420 W 21.60% -0.350 20.5 kg +20 W, +1.1 pp
LR7-54HJD-510M 510 W 25.00% -0.240 23.5 kg +110 W, cooler, +4.5 pp
AIKO-A495-MCE54Mw 495 W 24.80% -0.260 21.0 kg +95 W, cooler, +4.3 pp
LR7-54HJD-505M 505 W 24.70% -0.240 23.5 kg +105 W, cooler, +4.2 pp
AIKO-A490-MCE54Mw 490 W 24.50% -0.260 21.0 kg +90 W, cooler, +4.0 pp

Found 1783 panels of the same or similar size to this one, within ±10 mm. See them here Found 1914 panels of the same or similar size to this one, within ±25 mm. See them here Found 3392 panels of the same or similar size to this one, within ±50 mm. See them here Found 3970 panels of the same or similar size to this one, within ±100 mm. See them here

Common questions

6 answered
Are Runtech RT390-420WM panels suitable for a typical pitched roof?
Yes, the RT390-420WM series is designed for residential prosumer installations on pitched roofs. The modules measure 2384×1303×35 mm and weigh approximately 38.7 kg, which is compatible with standard roofing structures. The optimized aluminum frame and 3.2 mm tempered glass provide strong resistance to heavy snow loads typical of Central European winters.
What is the warranty on Runtech RT390-420WM solar panels?
The RT390-420WM series comes with a standard 10-year product and workmanship warranty and a 25-year linear power output guarantee. After 25 years of operation, the panel is rated to retain at least 80.7% of its nominal power output. Exact terms should be confirmed with your local distributor as agreements may vary by market.
What are the advantages of half-cut cells and Multi-Busbar (MBB) technology in the Runtech RT390-420WM?
Half-cut cell technology splits each cell in half, reducing internal resistance and lowering resistive power losses by 2-3% compared to standard full cells. Multi-Busbar shortens current pathways across the cell surface, minimizing the risk of micro-cracks and improving overall mechanical durability. The result is a module efficiency of up to 21.6% and a longer effective service life.
How do Runtech RT390-420WM panels handle partial shading from a chimney or nearby trees?
Thanks to the half-cut cell design, each RT390-420WM module is electrically divided into two independent halves. Shading on the lower section does not block output from the upper section and vice versa. Combined with strong PID resistance built into the cell architecture, this makes the series a reliable choice for rooftops with chimneys, dormers, or adjacent vegetation.
Do the RT390-420WM panels perform well in winter and at low temperatures?
Yes. The low temperature coefficient of the RT390-420WM series means that on cold, sunny winter days the modules can temporarily exceed their STC-rated output. The reinforced frame and 3.2 mm tempered glass also provide high snow-load resistance. This is a key advantage in Poland's climate, where standard panels lose significant output during summer heat peaks.
What does the RT390~420WM power range mean and which wattage bin should I choose for a home system?
The RT390~420WM designation covers power classes from 390 Wp to 420 Wp. Each panel is individually flash-tested under STC conditions and sorted into the corresponding wattage bin. For a typical 5-10 kWp residential installation, selecting the highest available bins (410-420 Wp) maximizes annual energy yield without requiring additional roof space or extra modules.
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