--- title: "JA Solar JAM66S30-480/MR Solar Panel: Specs & Datasheet | ComparePV" description: "JA Solar JAM66S30-480/MR solar panel. Specs: 20.20% efficiency, Monocrystalline cells, dimensions, warranty and temperature coefficient." source: "https://comparepv.com/panel/ja-solar-jam66s30-480-mr" image: "https://comparepv.com/og/panel/ja-solar-jam66s30-480-mr.png" updated: 2026-09-11 --- # JA Solar JAM66S30-480/MR Middle of its segment, modest efficiency 452 panels in the segment PERC 450-500 W ## Identity - **Manufacturer:** JA Solar - **Model:** JAM66S30-480/MR - **Series:** JAM66S30 480-505/MR - **Rated power:** 480 W - **Cell technology:** PERC ## How it compares Compared against segment PERC 450-500 W (452 panels). | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Power (Wp) | 480 W | 460 W | Typical | | | Module efficiency | 20.20% | 20.82% | Weak - bottom 5% | 12,039 | | Power density | 202.2 | 208.5 | Weak - bottom 7% | 12,037 | | Temperature coefficient | -0.350 | -0.350 | Typical | 10,489 | | Weight (kg) | 25.2 kg | 24.5 kg | Typical | | | Performance warranty | 25 yrs | 25 yrs | Typical | 9,912 | ### Full peer table | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Module efficiency | 20.20% | 20.82% | Weak - bottom 5% | 12,039 | | Power density | 202.2 | 208.5 | Weak - bottom 7% | 12,037 | | Temperature coefficient | -0.350 | -0.350 | Typical | 10,489 | | Weight per kWp | 52.5 | 53.1 | Typical | 6,090 | | Performance warranty | 25 yrs | 25 yrs | Typical | 9,912 | ### Watch out for - **20.20% module efficiency** - Bottom 5% of the PERC 450-500 W segment, against a median of 20.82%. Ranked 12,039th in the whole database. - **202.2 watts per square metre** - Bottom 7% of the PERC 450-500 W segment, against a median of 208.5. Ranked 12,037th in the whole database. - **Best for:** Residential, commercial and shaded-installations. - **Not ideal for:** Tight roof space and roofs where every square metre has to count. ## Specification ### Electrical - **Rated power (Pmax):** 480 W - **Efficiency:** 20.20 % - **Voltage at Pmax (Vmp):** 37.62 V - **Current at Pmax (Imp):** 12.76 A - **Open-circuit voltage (Voc):** 45.07 V - **Short-circuit current (Isc):** 13.65 A - **Max system voltage:** 1500 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:** 132 ### Physical - **Length:** 2093 mm - **Width:** 1134 mm - **Thickness:** 30 mm - **Weight:** 25.2 kg - **Area:** 2.37 m2 - **Power density:** 202.2 Wp/m2 ### Warranty and degradation - **Product warranty:** 12 years - **Performance warranty:** 25 years - **Output guaranteed at end of warranty:** 84.8 % - **First-year degradation:** 2.00 % - **Annual degradation:** 0.55 % - **Output after 30 years:** 394 W ## Rank in the whole catalogue | Measure | Position | | --- | --- | | Efficiency | 12039 of 14129 | | Power density | 12037 of 14129 | | Temperature coefficient | 10489 of 14129 | | Weight | 6090 of 14129 | | Warranty | 9912 of 14129 | ## Pros - **11BB MBB Half-Cut PERC Technology** - 132 half-cut cells in a 6×22 layout with 11-busbar multi-busbar (MBB) technology reduce series resistance and shading losses. Each module half operates independently, limiting the impact of partial shading from chimneys, dormers, or antennas on the full string. - **Guaranteed Positive Power Tolerance** - Modules are shipped at or above nameplate wattage, eliminating the risk of underdelivering contracted system capacity. This protects both system designers and investors from a gap between design output and real-world energy yield from day one. - **BNEF Tier-1 Manufacturer - Full Bankability** - JA Solar (founded 2005) is a continuous BloombergNEF Tier-1 manufacturer with annual module production capacity exceeding 100 GWp. Tier-1 status enables non-recourse project financing and minimizes counterparty risk across a 25-year system lifetime. - **IP68-Rated Junction Box** - IP68 protection ensures complete weatherproofing against prolonged water immersion - critical for installations exposed to heavy rainfall, condensation under roofing membranes, or high-pressure roof cleaning. - **25-Year Linear Power Warranty (84.8% at Year 25)** - JA Solar guarantees ≥98% power output after year 1 and ≥84.8% after 25 years, with maximum annual degradation capped at 0.55%/year, plus a 12-year product warranty. The linear warranty structure eliminates the step-function power loss found in older warranty contracts and simplifies LCOE modeling. ## Cons - **Discontinued Series (since 2023)** - The JAM66S30 480-505/MR series went out of production around 2023 (launched 2020). Availability is limited to distributor warehouse stock - expanding the system with identical modules or replacing failed units will become progressively harder and more expensive over a 10-15 year horizon. - **Lower Efficiency vs. Next-Gen Peer Technology** - PERC technology caps maximum module efficiency at 21.3%, while comparable peer products - Sunova Tangra M Pro HD and Q-SUN Qrystal N10 - achieve 22.7%. The 1.4 pp. gap translates to approximately 50-60 Wp of lost capacity over the same roof footprint (2.37 m²), a meaningful disadvantage in space-constrained installations. - **Monofacial Design - No Bifacial Gain** - The monofacial design generates no additional energy from ground albedo. In flat-roof or ground-mounted systems with a light-colored surface (concrete, gravel, snow), bifacial alternatives in the same power class can deliver 5-15% higher annual energy yield without any increase in installed area. ## About this series The JA Solar JAM66S30 480-505/MR series is designed for spaces where every square meter counts, or when installation space is limited. These modules feature **monocrystalline PERC cells in a half-cut configuration**, which practically translates to lower internal losses and better performance under partial shading-such as from a chimney, window frame, or neighboring trees. The application of **multi-busbar technology** improves current collection from the cells and enhances resistance to micro-cracks, ensuring the module maintains its performance characteristics over time. This series also offers **positive power tolerance**, minimizing the risk that the actual installation power will be lower than expected. The construction is designed for demanding operating conditions-robust mechanical loads and a **IP68 junction box** ensure trouble-free operation for years to come. This is an excellent choice for residential and commercial installations, especially when high power density, reliable yield, and durability that sets the module apart from competitors are priorities. ## Notable figures - At 20.2% efficiency, this panel is 0.6pp below the \*\*PERC 450-500W\*\* median of 20.8% - 202.2 W/m² power density is 6.3 W/m² below \*\*PERC 450-500W\*\* median (208.5 W/m²) - requires larger installation area - At -0.35%/°C, hot weather performance is typical for \*\*PERC 450-500W\*\* panels - Ranked #12039 out of 14129 panels for efficiency in the database ## Questions ### Is the JA Solar JAM66S30 480-505/MR series still available for purchase? The JAM66S30 480-505/MR series has been discontinued by JA Solar and is no longer in production. Modules may still be available as existing distributor stock. If you're planning a new installation, check with your dealer for current inventory or consider a newer JA Solar series with comparable specifications. ### What is the maximum power output of the JAM66S30, and how many panels do I need for a home system? The top model in this series delivers 505 Wp of peak power. A typical residential 5 kWp system would require around 10 modules. Thanks to a positive power tolerance, actual output may slightly exceed the nominal rating, making energy yield predictable and consistent throughout the system's operational lifetime. ### Do JAM66S30 480-505/MR panels perform well under partial shading, such as from a chimney or dormer? Yes. The half-cut PERC cell design splits each cell into two halves, so shading on one part of the module limits losses only within that section rather than the entire panel. Multi-busbar technology further reduces resistive losses and improves current collection from partially shaded cells. In practice, JAM66S30 modules outperform conventional full-cell modules under non-uniform irradiance conditions. ### What warranties are included with the JA Solar JAM66S30 480-505/MR? JA Solar provides a 12-year product warranty covering material and manufacturing defects, plus a 25-year linear power warranty guaranteeing at least 84.8% of nominal output after 25 years. As a Tier 1 manufacturer, JA Solar's financial standing makes it more likely these warranty commitments will be honored over the full declared period. ### What does an IP68-rated junction box mean on the JAM66S30, and why does it matter? IP68 indicates full dust-tightness and resistance to continuous water submersion. On a PV module, this means the junction box withstands heavy rainfall, standing water on flat roofs, and prolonged humidity. It is especially important for flat-roof installations or high-precipitation regions, where a lower-rated junction box could corrode or fail within just a few seasons. ### How heavy is the JAM66S30 panel, and can a standard roof structure support it? Each module weighs approximately 25.2 kg with dimensions of 2093 × 1134 × 30 mm - typical for panels in this power class. Most standard residential roof structures, both pitched and flat, can support this load without modification. An installer should assess the roof condition and select appropriate mounting hardware suited to the specific structure before installation. ## Datasheet [Manufacturer datasheet (PDF)](https://comparepv.com/datasheets/500W-JAM66S30-480-505-MR-5ce6d32191f1.pdf) ## Alternatives | Panel | Power | How it differs | | --- | --- | --- | | [Longi Solar LR7-54HJD-510M](https://comparepv.com/panel/longi-lr7-54hjd-510m) | 510 W | Cooler, +4.8 pp, +5 yr warranty | | [AIKO AIKO-A495-MCE54Mw](https://comparepv.com/panel/aiko-aiko-a495-mce54mw) | 495 W | Cooler, +4.6 pp, +5 yr warranty | | [Longi Solar LR7-54HJD-505M](https://comparepv.com/panel/longi-lr7-54hjd-505m) | 505 W | Cooler, +4.5 pp, +5 yr warranty | | [WINAICO WST-505BKX54-A2](https://comparepv.com/panel/winaico-wst-505bkx54-a2) | 505 W | Cooler, +4.5 pp, +5 yr warranty | | [AIKO AIKO-A490-MCE54Mw](https://comparepv.com/panel/aiko-aiko-a490-mce54mw) | 490 W | Cooler, +4.3 pp, +5 yr warranty | | [Longi Solar LR7-54HJD-500M](https://comparepv.com/panel/longi-lr7-54hjd-500m) | 500 W | Cooler, +4.3 pp, +5 yr warranty | | [Talesun CIPRO-TN9C54M-500W](https://comparepv.com/panel/talesun-cipro-tn9c54m-500w) | 500 W | Cooler, +4.3 pp, +5 yr warranty | | [JA Solar JAM66D30-480/MB/1500V](https://comparepv.com/panel/shanghai-ja-solar-technology-co-ltd-jam66d30-480-mb-1500v) | 480 W | Heavier, +5 yr warranty | | [JA Solar JAM66S30-485/MR](https://comparepv.com/panel/ja-solar-jam66s30-485-mr) | 485 W | Very close match | | [JA Solar JAM66D30-485/MB/1500V](https://comparepv.com/panel/shanghai-ja-solar-technology-co-ltd-jam66d30-485-mb-1500v) | 485 W | Heavier, +5 yr warranty | | [JA Solar JAM66S30-490/MR](https://comparepv.com/panel/ja-solar-jam66s30-490-mr) | 490 W | +10 W, +0.4 pp | | [JA Solar JAM66D30-490/MB/1500V](https://comparepv.com/panel/shanghai-ja-solar-technology-co-ltd-jam66d30-490-mb-1500v) | 490 W | Heavier, +0.4 pp, +5 yr warranty | | [JA Solar JAM66S30-495/MR](https://comparepv.com/panel/ja-solar-jam66s30-495-mr) | 495 W | +15 W, +0.7 pp | | [Gamko New Energy GKA120N-PRO-590W](https://comparepv.com/panel/gamko-new-energy-gka120n-pro-590w) | 590 W | +110 W, +3.6 pp, +5 yr warranty | | [Gamko New Energy GKA120N-PRO-585W](https://comparepv.com/panel/gamko-new-energy-gka120n-pro-585w) | 585 W | +105 W, +3.4 pp, +5 yr warranty | | [Bisol BGO 580](https://comparepv.com/panel/bisol-bgo-580) | 580 W | +100 W, cooler, +3.3 pp | --- Source: https://comparepv.com/panel/ja-solar-jam66s30-480-mr Not in this file, on the page: a thirty-year output simulator and alternatives filtered by how closely they match these dimensions.