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JA Solar JAM54S31-385/MR

JAM54S31-385/MR

385 Wp PERC
ComparePV verdict

Light for its output, no clear weak spot

Rank 12,528 of 14,005
Compare panels Datasheet PDF
Power (Wp)
385
Typical for its class
Efficiency (%)
19.70
Typical · median 19.90%
Density (Wp/m²)
197.2
Typical · median 199.0
Temp (%/°C)
-0.350
Typical · median -0.350
Weight (kg)
19.5
Strong · 1.9 kg below median
Warranty (yrs)
25
Typical · median 25 yrs

The JA Solar JAM54S31 380-405/MR series is designed for maximum energy yield from limited rooftop space, without compromising on longevity. These modules utilize half-cut technology, which better withstands partial shading and reduces the risk of localized overheating, as well as multi-busbar (MBB) construction, improving current conduction and operational stability under real-world conditions. In practice, this translates to more predictable energy production throughout the day, even with poorer weather conditions or dirt on the glass.

Another highlight is the enhanced mechanical durability, which is crucial in Poland's climate, especially under snow and wind loads. Thanks to the Full Black aesthetic (depending on the version), the series is often chosen for single-family homes and buildings with high visual standards. This is an excellent choice for installers and investors who wish to achieve high power density, durability, and a refined appearance - without paying for premium solutions.

Ranking

579 panels in the segment PERC 350-400 W
Metric This panel Median Position in segment Overall rank
Module efficiency 19.70% 19.90% Typical 12,511
Power density 197.2 199.0 Typical 12,493
Temperature coefficient -0.350 -0.350 Typical 10,419
Weight per kWp 50.6 55.8 Strong · top 7% 4,091
Performance warranty 25 yrs 25 yrs Typical 9,798
Colour key Strong - top 25% Typical - middle 50% Weak - bottom 25%

Signals from the data

5 positive · 3 caution
Best for

Residential, commercial and shaded-installations.

Strengths
50.6 kg per kWp

Top 7% of the PERC 350-400 W segment, against a median of 55.8. Ranked 4,091st in the whole database.

What owners get
Half-cut cells + 11-busbar MBB

Splitting cells in half reduces series resistance and lowers hot-spot risk under partial shading. The 11-busbar MBB layout shortens current paths by up to 30% compared to 5-busbar predecessors, improving energy yield at low irradiance and under diffuse light conditions.

Tier-1 BNEF bankable manufacturer (Q2 2026)

JA Solar holds continuous BNEF Tier-1 bankable status, confirmed on the Q2 2026 list. With annual manufacturing capacity exceeding 80 GW and operations since 2005, the company presents minimal counterparty risk for project finance.

20.7% efficiency competitive within segment

The 405 Wp variant reaches 20.7% module efficiency — on par with EGing PV STAR (20.74%) and VSUN405-108BMH (20.74%), and above Goldi GS10-M108-BF (20.66%), confirming the series' competitiveness within the 108-cell PERC power class.

Mechanical durability: 5400/2400 Pa

IEC 61215 and IEC 61730 certified to withstand 5400 Pa front load (snow) and 2400 Pa rear load (wind) — values relevant to Central European climates where snow load standards reach 1.5–3.0 kN/m² depending on zone.

Trade-offs
Discontinued series (EOL ~2023)

Production of the JAM54S31 380-405/MR was discontinued around 2023. Module availability is limited to remaining warehouse stock, complicating replacement sourcing for damaged units and potentially affecting warranty claim processing given the inactive production line.

P-type PERC – higher LID and degradation rate

P-type PERC cells exhibit initial LID of 1.5–3% due to boron-oxygen defects, versus 0.2–0.5% for N-type TOPCon. Annual degradation for PERC runs at 0.45–0.55% vs. 0.30–0.40% for TOPCon, resulting in ~84.8% power retention after 25 years compared to >90% for TOPCon modules — translating to a higher LCOE for new installations.

Monofacial only – no bifacial gain

The series is monofacial (is_bifacial = false), while comparable products in the same power class (e.g., Goldi GS10-M108-BF) offer an additional 5–15% rear-side yield under favorable albedo conditions. At identical nameplate power, this results in lower real-world annual energy output on installations over light-colored surfaces.

Notes from the database
  • At 19.7% efficiency, this panel is on par with typical PERC 0-400W modules
  • At 197.2 W/m² power density, roof space requirements are typical for PERC 0-400W panels
  • Temperature coefficient of -0.35%/°C matches the PERC 0-400W median
  • At 19.5 kg, weight matches the PERC 0-400W median
  • #12511 for efficiency, #10419 for temperature performance out of 14005 panels

Specifications

Open datasheet PDF
Nominal power (Pmax) 385 Wp Nameplate at 1000 W/m², 25 °C
Module efficiency 19.70 % Typical Segment median 19.90%
Vmpp · Impp 30.46 V · 12.64 A Operating point at max power
Voc · Isc 36.71 V · 13.52 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 19.5 kg Strong Strong · 1.9 kg below median
Cells 108 · PERC Monocrystalline
Coefficient Pmax -0.350 %/°C Typical median -0.350 of its segment
Coefficient Voc · Isc -0.275 · 0.045 %/°C
NOCT 45 °C At 800 W/m², 20 °C ambient
Product warranty 12 years Hardware defects only
Performance warranty 25 years Typical median 25 yrs · median 25 yrs
End-of-warranty output 84.8 % Equals 316 W guaranteed
Degradation 2.00 → 0.55 % First year, then annual

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 -0.350
-
Filter these
Size
Panel Power Eff. Temp. Weight Difference
JA Solar JAM54S31-385/MR 385 W 19.70% -0.350 19.5 kg You are here
GKA210M340W 340 W 23.00% - 16.2 kg -45 W, +3.3 pp, +5 yr warranty
GKA210M360W 360 W 23.00% - 16.2 kg Lighter, +3.3 pp, +5 yr warranty
GKA210M380W (1/4*4*38) 380 W 23.00% - 17.1 kg Lighter, +3.3 pp, +5 yr warranty
GKA210M400W (1/2*4*20) 400 W 23.00% - 18.0 kg +15 W, +3.3 pp, +5 yr warranty
GKA210M400W (1/4*4*40) 400 W 23.00% - 18.0 kg +15 W, +3.3 pp, +5 yr warranty
GKA210M380W (1/2*4*19) 380 W 23.00% - 17.1 kg Lighter, +3.3 pp, +5 yr warranty
LX-435M/182-108+ GG 435 W 22.81% -0.240 23.6 kg +50 W, cooler, +3.1 pp
JT435SYk(B) 435 W 22.70% -0.240 23.0 kg +50 W, cooler, +3.0 pp
SPR-MAX3-430-R 430 W 22.70% -0.270 21.2 kg Cooler, +3.0 pp, +15 yr warranty
LX-435M/182-108+ 435 W 22.61% -0.300 21.5 kg +50 W, cooler, +2.9 pp
JAM54S31-380/MR 380 W 19.50% -0.350 19.5 kg Very close match
JAM54D30-390/MB/1500V 390 W 19.90% -0.350 23.6 kg Heavier, +5 yr warranty
JAM54S31-390/MR 390 W 20.00% -0.350 19.5 kg +0.3 pp
JAM54D30-395/MB/1500V 395 W 20.20% -0.350 23.6 kg Heavier, +0.5 pp, +5 yr warranty
JAM54S31-395/MR 395 W 20.20% -0.350 19.5 kg +10 W, +0.5 pp
JAM54S30-400/MR 400 W 20.50% -0.350 19.5 kg +15 W, +0.8 pp
LR7-54HJD-510M 510 W 25.00% -0.240 23.5 kg +125 W, cooler, +5.3 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
What do half-cut cell technology and MBB mean in the JA Solar JAM54S31 380-405/MR panels, and why does it matter?
Half-cut technology splits each PERC cell in two, reducing resistive losses and improving tolerance to partial shading — for example from a chimney or antenna. The multi-busbar design with 11 busbars enhances current collection and lowers the risk of micro-cracks. In practice, this means more consistent and predictable energy output throughout the day, even under diffuse light or overcast conditions.
What is the warranty on the JA Solar JAM54S31-405/MR panels?
The manufacturer offers a 12-year product warranty covering material and workmanship defects. The linear power warranty runs for 25 years with a maximum annual degradation of 0.55%, guaranteeing at least 82.7% of rated output after 25 years of operation. Both warranty tiers are standard for a Tier 1 manufacturer such as JA Solar.
How does the JA Solar JAM54S31-405/MR perform in winter and low-light conditions?
PERC cell technology improves light absorption at low incidence angles typical of fall and winter in Central Europe. The temperature coefficient of -0.35%/°C means panels actually operate more efficiently in cold weather than in summer heat. The 11-busbar MBB construction further stabilizes output under diffuse, overcast conditions and with light soiling on the glass surface.
Can the JAM54S31 380-405/MR series handle heavy snow loads and strong winds?
The JAM54S31 380-405/MR modules are certified for snow loads up to 5,400 Pa and wind loads up to 2,400 Pa, comfortably meeting the demands of Central European climates. Each panel weighs 19.5 kg with dimensions of 1722 x 1134 x 30 mm, making rooftop handling and installation on standard pitched-roof racking systems straightforward. The reinforced aluminum frame ensures long-term structural stability.
Is the JA Solar JAM54S31 380-405/MR series available in a Full Black version and who is it designed for?
Yes, the JAM54S31 380-405/MR series was offered in a Full Black variant featuring black cells, a black frame, and a black backsheet. It is a popular choice for single-family homes and buildings with elevated aesthetic requirements. The electrical specifications are identical to the standard version; the only difference is a slightly higher operating temperature due to the darker surface absorbing more heat.
Is the JA Solar JAM54S31 380-405/MR series still available for purchase?
The JAM54S31 380-405/MR series has been discontinued and is no longer actively distributed by JA Solar. Remaining stock may still be found through distributors or on the secondary market. If you need similar performance with full warranty support, consider newer JA Solar series based on PERC or TOPCon technology, which offer higher power output and current after-sales coverage.
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