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JA Solar JAM54S30-425/MR
JA Solar Brand review

JAM54S30-425/MR

425 Wp PERC
ComparePV verdict

Efficiency leader, no clear weak spot

Rank 10,817 of 14,005
Compare panels Datasheet PDF
Power (Wp)
425
Typical for its class
Efficiency (%)
21.80
Strong · top 1%
Density (Wp/m²)
217.6
Strong · top 1%
Temp (%/°C)
-0.350
Typical · median -0.350
Weight (kg)
19.5
Strong · 2.5 kg below median
Warranty (yrs)
25
Typical · median 25 yrs

The JA Solar JAM54S30 MR series are panels in the 54-cell format (in practice, a half-cut configuration), designed specifically for single-family homes and multi-family buildings, where high efficiency per square meter and reliable performance under varying conditions are key. The use of P-type Mono PERC cells helps maintain stable energy production throughout the day, even under weaker sunlight, while the half-cut structure minimizes power losses during partial shading and improves the module's performance in real rooftop installations.

A key feature is the multi-busbar technology, which enhances current collection from the cells and supports uniform operation under thermal stress. For installers and investors, this means easier string design and reduced susceptibility to common roofing issues-such as chimneys, flashing, antennas, or seasonal shading.

JAM54S30 MR is an excellent choice for homeowners seeking low energy costs over the lifecycle without investing in premium solutions, while also desiring a module optimized for reliability and aesthetic refinement.

Ranking

954 panels in the segment PERC 400-450 W
Metric This panel Median Position in segment Overall rank
Module efficiency 21.80% 20.60% Strong · top 1% 7,022
Power density 217.6 206.2 Strong · top 1% 7,172
Temperature coefficient -0.350 -0.350 Typical 10,419
Weight per kWp 45.9 53.0 Strong · top 4% 907
Performance warranty 25 yrs 25 yrs Typical 9,798
Colour key Strong - top 25% Typical - middle 50% Weak - bottom 25%

Signals from the data

7 positive · 3 caution
Best for

Residential and shaded-installations.

Strengths
21.80% module efficiency

Top 1% of the PERC 400-450 W segment, against a median of 20.60%. Ranked 7,022nd in the whole database.

217.6 watts per square metre

Top 1% of the PERC 400-450 W segment, against a median of 206.2. Ranked 7,172nd in the whole database.

45.9 kg per kWp

Top 4% of the PERC 400-450 W segment, against a median of 53.0. Ranked 907th in the whole database.

What owners get
Efficiency leads the peer segment

The 425 Wp variant delivers 21.8% module efficiency, outperforming all direct peers in the same power bracket: Trina Solar Vertex S (21.3%), Hyundai DG G12 PERC Shingled (21.4%), and Tongwei TERRA 5K (21.4%). This translates into higher annual energy yield per square meter of rooftop.

11BB half-cut – reduced shading losses

The 11-busbar (11BB) cell configuration combined with half-cut cell splitting lowers series resistance and significantly reduces losses under partial shading. This is a critical advantage for typical residential rooftops with obstructions such as chimneys, dormers, or antennas.

BNEF Tier-1 manufacturer – fully bankable

JA Solar has maintained BNEF Tier-1 bankable manufacturer status for multiple consecutive years and surpassed 100 GW of annual production capacity in 2025. Tier-1 standing means lenders accept these modules in non-recourse project finance without additional manufacturer risk due diligence.

25-year linear power warranty, 0.55%/yr degradation

The manufacturer guarantees ≥84.8% of rated power after 25 years with an annual degradation rate of 0.55%. These figures align with best-in-class standards for P-type Mono PERC modules and support a low LCOE over the system's lifetime.

Trade-offs
Series discontinued (~2023)

The JAM54S30 MR line reached end of production around 2023. New units are only available from distributor stock, with availability declining over time. Expanding an existing installation with identical modules may become impossible, raising the risk of MPPT mismatch within a string.

P-type PERC — no N-type TOPCon advantages

Relative to the listed peers (Trina Vertex S, Tongwei TERRA 5K — also PERC), the technology gap is neutral. However, by 2024–2026 the broader market offers N-type TOPCon modules at comparable price points with lower LID, higher bifacial gain, and better performance under diffuse irradiance, placing the JAM54S30 MR at a technological disadvantage against current offerings.

12-year product warranty — below premium tier

The 12-year product warranty is the market standard for this segment, but select manufacturers (e.g., REC Group, SunPower) provide 20–25 year product warranties on premium modules. For investors targeting a 25+ year system lifetime, this represents a measurable difference in factory-defect coverage.

Notes from the database
  • At 21.8% efficiency, this panel is 1.2pp above typical PERC 400-450W modules (median: 20.6%)
  • 217.6 W/m² power density - 11.4 W/m² more than PERC 400-450W median (206.2 W/m²), more power per roof area
  • At -0.35%/°C, hot weather performance is typical for PERC 400-450W panels
  • Weight of 19.5 kg (2.5 kg below PERC 400-450W median of 22.0 kg) allows easier transport and roof mounting
  • Ranked #7022 out of 14005 panels for efficiency in the database

Specifications

Open datasheet PDF
Nominal power (Pmax) 425 Wp Nameplate at 1000 W/m², 25 °C
Module efficiency 21.80 % Strong Segment median 20.60%
Vmpp · Impp 31.98 V · 13.29 A Operating point at max power
Voc · Isc 37.72 V · 14.18 A Sizes the string length
Max system voltage 1000 V Longer strings than 1000 V modules
Dimensions 1722×1134×30 mm · 1.95 m² of roof
Weight 19.5 kg Strong Strong · 2.5 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 87.4 % Equals 349 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 JAM54S30-425/MR 425 W 21.80% -0.350 19.5 kg You are here
SPR-MAX7-475 475 W 24.00% -0.270 21.1 kg Cooler, +2.2 pp, +15 yr warranty
JST-EDMH-(445-465)W-TD (465W class) 465 W 23.81% -0.300 20.5 kg Cooler, +2.0 pp, +5 yr warranty
JAT54S40-475/LR 475 W 23.80% -0.260 19.3 kg +50 W, cooler, +2.0 pp
TWMNH-48HW475 475 W 23.80% -0.280 23.7 kg +50 W, cooler, +2.0 pp
CHSM48RN(DG)/F-BH-475 475 W 23.80% -0.290 24.5 kg +50 W, cooler, +2.0 pp
AIKO-A475-MCE54Mw 475 W 23.80% -0.260 21.0 kg +50 W, cooler, +2.0 pp
AIKO-A475-MAH54Mw 475 W 23.80% -0.260 21.5 kg +50 W, cooler, +2.0 pp
JAM54S31-380/MR 380 W 19.50% -0.350 19.5 kg -45 W, -2.3 pp
JAM54S31-385/MR 385 W 19.70% -0.350 19.5 kg -40 W, -2.1 pp
JAM54D30-390/MB/1500V 390 W 19.90% -0.350 23.6 kg Heavier, -1.9 pp, +5 yr warranty
JAM54S31-390/MR 390 W 20.00% -0.350 19.5 kg -35 W, -1.8 pp
JAM54D30-395/MB/1500V 395 W 20.20% -0.350 23.6 kg Heavier, -1.6 pp, +5 yr warranty
JAM54S31-395/MR 395 W 20.20% -0.350 19.5 kg -30 W, -1.6 pp
JAM54S30-400/MR 400 W 20.50% -0.350 19.5 kg -25 W, -1.3 pp
JAM54D30-400/MB/1500V 400 W 20.40% -0.350 23.6 kg Heavier, -1.4 pp, +5 yr warranty
LR7-54HJD-510M 510 W 25.00% -0.240 23.5 kg +85 W, cooler, +3.2 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
Is the JA Solar JAM54S30 MR series still available for purchase?
The JAM54S30 MR series has been discontinued and is no longer an active JA Solar product line. Some distributors and wholesalers may still carry stock. For new installations, we recommend looking at current JA Solar series with full manufacturer support and readily available supply.
What warranty does the JA Solar JAM54S30 MR carry?
JA Solar provides a 12-year product warranty covering material and workmanship defects, plus a 25-year linear power warranty. After 25 years the module should retain at least 80.7% of rated power. Maximum annual degradation is 0.55%, which is competitive among Tier 1 PERC modules and supports a low LCOE over the system's lifetime.
How well do JAM54S30 MR panels handle partial shading on a rooftop?
The half-cut cell design splits each cell into two halves, significantly reducing the impact of localized shading from a chimney, dormer, or antenna on overall module output. Three bypass diodes inside the IP68 junction box provide additional protection. Power losses under partial shading are considerably lower than with conventional full-cell modules.
What is multi-busbar technology and why does it matter for the JAM54S30 MR?
Multi-busbar — 11 busbars in this series — replaces a few wide conductors with a grid of thin wires across the cell surface. This shortens the current path to the busbar, reduces resistive losses, and improves module efficiency. It also increases resistance to cell microcracks and supports more uniform output under variable irradiance conditions.
What is the peak power output and efficiency of the JAM54S30 425/MR panel?
The top variant of the series delivers 425 Wp at a module efficiency of approximately 21.8%. With dimensions of 1722×1134 mm and a weight of 21.5 kg, it is one of the more compact modules in this power class, making rooftop transport and installation on standard racking systems straightforward.
Are JAM54S30 MR panels suitable for a residential sloped roof?
Yes, the JAM54S30 MR was designed for residential rooftop installations on sloped surfaces. The 1722×1134 mm format and approximately 21.5 kg weight are compatible with standard mounting systems. Half-cut and multi-busbar technologies reduce shading losses from roof penetrations, while the -40°C to +85°C operating range ensures reliable year-round performance.
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