--- title: "JA Solar JAM54S30-425/MR 425W Solar Panel - Specs & Review | ComparePV" description: "JA Solar JAM54S30-425/MR 425W solar panel. Specs: 21.80% efficiency, Monocrystalline cells, dimensions, warranty and temperature coefficient." source: "https://comparepv.com/panel/ja-solar-jam54s30-425-mr" updated: 2026-09-11 --- # JA Solar JAM54S30-425/MR Efficiency leader, no clear weak spot 954 panels in the segment PERC 400-450 W ## Identity - **Manufacturer:** JA Solar - **Model:** JAM54S30-425/MR - **Series:** JAM54S30 MR - **Rated power:** 425 W - **Cell technology:** PERC ## How it compares Compared against segment PERC 400-450 W (954 panels). | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Power (Wp) | 425 W | 410 W | Typical | | | 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 (kg) | 19.5 kg | 22.0 kg | Strong - top 4% | | | Performance warranty | 25 yrs | 25 yrs | Typical | 9,798 | ### Full peer table | Measure | This panel | Segment median | Standing | 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 | ### 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. - **Best for:** Residential and shaded-installations. ## Specification ### Electrical - **Rated power (Pmax):** 425 W - **Efficiency:** 21.80 % - **Voltage at Pmax (Vmp):** 31.98 V - **Current at Pmax (Imp):** 13.29 A - **Open-circuit voltage (Voc):** 37.72 V - **Short-circuit current (Isc):** 14.18 A - **Max system voltage:** 1000 V ### Temperature - **Temperature coefficient of Pmax:** -0.350 %/degC - **Temperature coefficient of Voc:** -0.275 %/degC - **Temperature coefficient of Isc:** 0.045 %/degC - **NOCT:** 45 degC ### Cell and construction - **Cell type:** Monocrystalline - **Cell technology:** PERC - **Cell count:** 108 ### Physical - **Length:** 1722 mm - **Width:** 1134 mm - **Thickness:** 30 mm - **Weight:** 19.5 kg - **Area:** 1.95 m2 - **Power density:** 217.6 Wp/m2 ### Warranty and degradation - **Product warranty:** 12 years - **Performance warranty:** 25 years - **Output guaranteed at end of warranty:** 87.4 % - **First-year degradation:** 2.00 % - **Annual degradation:** 0.55 % - **Output after 30 years:** 349 W ## Rank in the whole catalogue | Measure | Position | | --- | --- | | Efficiency | 7022 of 14005 | | Power density | 7172 of 14005 | | Temperature coefficient | 10419 of 14005 | | Weight | 907 of 14005 | | Warranty | 9798 of 14005 | ## Pros - **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. ## Cons - **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. ## About this series 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. ## Notable figures - 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 ## Questions ### 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. ## Datasheet [Manufacturer datasheet (PDF)](https://comparepv.com/datasheets/18d5c964e98c999-8f17f85e83f7.pdf) ## Alternatives | Panel | Power | How it differs | | --- | --- | --- | | [Maxeon SPR-MAX7-475](https://comparepv.com/panel/maxeon-spr-max7-475) | 475 W | Cooler, +2.2 pp, +15 yr warranty | | [Just Solar JST-EDMH-(445-465)W-TD (465W class)](https://comparepv.com/panel/just-solar-jst-edmh-445-465-w-td-465w-class) | 465 W | Cooler, +2.0 pp, +5 yr warranty | | [JA Solar JAT54S40-475/LR](https://comparepv.com/panel/ja-solar-jat54s40-475-lr) | 475 W | +50 W, cooler, +2.0 pp | | [Tongwei TWMNH-48HW475](https://comparepv.com/panel/tongwei-solar-twmnh-48hw475) | 475 W | +50 W, cooler, +2.0 pp | | [Astronergy CHSM48RN(DG)/F-BH-475](https://comparepv.com/panel/astronergy-chint-new-energy-technology-co-ltd-chsm48rn-dg-f-bh-475) | 475 W | +50 W, cooler, +2.0 pp | | [AIKO AIKO-A475-MCE54Mw](https://comparepv.com/panel/aiko-aiko-a475-mce54mw) | 475 W | +50 W, cooler, +2.0 pp | | [AIKO AIKO-A475-MAH54Mw](https://comparepv.com/panel/aiko-aiko-a475-mah54mw) | 475 W | +50 W, cooler, +2.0 pp | | [JA Solar JAM54S31-380/MR](https://comparepv.com/panel/ja-solar-jam54s31-380-mr) | 380 W | -45 W, -2.3 pp | | [JA Solar JAM54S31-385/MR](https://comparepv.com/panel/ja-solar-jam54s31-385-mr) | 385 W | -40 W, -2.1 pp | | [JA Solar JAM54D30-390/MB/1500V](https://comparepv.com/panel/ja-solar-jam54d30-390-mb-1500v) | 390 W | Heavier, -1.9 pp, +5 yr warranty | | [JA Solar JAM54S31-390/MR](https://comparepv.com/panel/ja-solar-jam54s31-390-mr) | 390 W | -35 W, -1.8 pp | | [JA Solar JAM54D30-395/MB/1500V](https://comparepv.com/panel/ja-solar-jam54d30-395-mb-1500v) | 395 W | Heavier, -1.6 pp, +5 yr warranty | | [JA Solar JAM54S31-395/MR](https://comparepv.com/panel/ja-solar-jam54s31-395-mr) | 395 W | -30 W, -1.6 pp | | [JA Solar JAM54S30-400/MR](https://comparepv.com/panel/ja-solar-jam54s30-400-mr) | 400 W | -25 W, -1.3 pp | | [JA Solar JAM54D30-400/MB/1500V](https://comparepv.com/panel/ja-solar-jam54d30-400-mb-1500v) | 400 W | Heavier, -1.4 pp, +5 yr warranty | | [Longi Solar LR7-54HJD-510M](https://comparepv.com/panel/longi-lr7-54hjd-510m) | 510 W | +85 W, cooler, +3.2 pp | --- Source: https://comparepv.com/panel/ja-solar-jam54s30-425-mr Not in this file, on the page: a thirty-year output simulator and alternatives filtered by how closely they match these dimensions.