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JAM54S40-455/LR vs JAT54S40-485/LR 11 of 19 identical Swap Change panels

JA Solar JAM54S40-455/LR vs JA Solar JAT54S40-485/LR

JA Solar JAM54S40-455/LR
JAM54S40-455/LR
455 Wp 22.80 % TOPCon
Open panel page Datasheet PDF
VS
JA Solar JAT54S40-485/LR
JAT54S40-485/LR
485 Wp 24.30 % TOPCon
Open panel page Datasheet PDF
The verdict

JAT54S40-485/LR leads on the differences that matter

The largest is module efficiency: 1.50 pp more efficient. 11 of 19 comparable parameters are identical.

See all 8 differences
How alike are they
11 of 19 comparable
parameters are identical
identical differs
01

What actually differs

8 of 19 parameters
Parameter JAM54S40-455/LR JAT54S40-485/LR Difference
Module efficiency 22.80 % 24.30 % 1.50 pp more efficient
Power density 227.7 Wp/m² 242.7 Wp/m² 15.0 Wp/m² higher
Temperature coefficient -0.290 %/°C -0.260 %/°C 0.030 %/°C better in heat
Annual degradation 0.40 %/yr 0.55 %/yr 0.15 %/yr slower
Rated power 455 Wp 485 Wp 30 W more power
Weight per kWp 44.0 kg/kWp 39.8 kg/kWp 4.2 kg/kWp lighter
Open-circuit voltage 39.50 V 41.17 V 1.67 V apart
Voltage at max power 33.00 V 35.13 V 2.13 V apart
02

What it means on a roof

Thirty years of production
Each panel's own declared degradation curve, at 1,200 kWh/kWp a year
JAM54S40-455/LR
15,266 kWh
JAT54S40-485/LR
15,893 kWh
Lifetime gap
627 kWh
Output when it is hot
Rated power carried across the range a module actually sees
Scenario JAM54S40-455/LR JAT54S40-485/LR
Standard test conditions 25 °C 100.0% of rated power 455 W 485 W
Cool, bright day 40 °C 95.7% of rated power 435 W 466 W
Typical summer roof 55 °C 91.3% of rated power 415 W 447 W
Hot roof 70 °C 87.0% of rated power 396 W 428 W
03

Full specification

Parameter JAM54S40-455/LR JAT54S40-485/LR Difference
Power and efficiency
Rated power 455 Wp 485 Wp +30 W for JAT54S40-485/LR
Module efficiency 22.80 % 24.30 % +1.50 pp for JAT54S40-485/LR
Power density 227.7 Wp/m² 242.7 Wp/m² +15.0 Wp/m² for JAT54S40-485/LR
Open-circuit voltage 39.50 V 41.17 V 1.67 V apart
Voltage at max power 33.00 V 35.13 V 2.13 V apart
Short-circuit current 14.56 A 15.02 A Effectively the same
Current at max power 13.79 A 13.81 A Effectively the same
Temperature
Temperature coefficient -0.290 %/°C -0.260 %/°C +0.030 %/°C for JAT54S40-485/LR
Mechanical
Dimensions 1762x1134x30 mm 1762x1134x30 mm Same
Module area 1.998 m² 1.998 m² Same
Weight 20.0 kg 19.3 kg Effectively the same
Weight per kWp 44.0 kg/kWp 39.8 kg/kWp -4.2 kg/kWp for JAT54S40-485/LR
Warranty and degradation
Product warranty 15 yrs 15 yrs Same
Performance warranty 30 yrs 30 yrs Same
Annual degradation 0.40 %/yr 0.55 %/yr -0.15 %/yr for JAM54S40-455/LR
Technology
Cell technology TOPCon TOPCon Same
Cell type Monocrystalline Monocrystalline Same
Cell count 108 108 Same
Bifacial No No Same
04

Against the whole database

14,005 panels
Efficiency
#2,714 vs #131
JAT54S40-485/LR leads by 2,583 places
Power density
#2,888 vs #140
JAT54S40-485/LR leads by 2,748 places
Heat behaviour
#2,165 vs #511
JAT54S40-485/LR leads by 1,654 places
Weight
#365 vs #158
JAT54S40-485/LR leads by 207 places
Warranty
#21 vs #21
Tied - the same position in the database
Overall
#7,691 vs #4,770
JAT54S40-485/LR leads by 2,921 places
05

More useful comparisons

Open the full database
Same series, other bin
JA Solar JAM54S40-455/LR vs JA Solar JAT54S40-480/LR
8 differences, the largest is module efficiency
Same series, other bin
JA Solar JAM54S40-455/LR vs JA Solar JAT54S40-475/LR
8 differences, the largest is module efficiency
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JA Solar JAM54S40-455/LR vs JA Solar JAM54D40-475/LR
8 differences, the largest is module efficiency
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JA Solar JAM54S40-455/LR vs JA Solar JAT54S40-470/LR
8 differences, the largest is module efficiency
Same series, other bin
JA Solar JAM54S40-455/LR vs JA Solar JAM54D40-470/LR
6 differences, the largest is module efficiency
Same series, other bin
JA Solar JAM54S40-455/LR vs JA Solar JAT54S40-465/LR
8 differences, the largest is module efficiency
06

Written summary

07

Questions about this pairing

Which panel is better: JA Solar JAM54S40-455/LR or JA Solar JAT54S40-485/LR?
According to our database: JA Solar JAT54S40-485/LR has higher module efficiency (24.30% vs 22.80%); JA Solar JAT54S40-485/LR tolerates heat better (temp coeff -0.260%/°C vs -0.290%/°C). See the full spec comparison and 30-year energy simulation above for a complete picture.
What is the efficiency of JA Solar JAM54S40-455/LR and JA Solar JAT54S40-485/LR?
JA Solar JAM54S40-455/LR has a module efficiency of 22.80%, while JA Solar JAT54S40-485/LR is 24.30%. Higher efficiency means more electricity from the same roof area - useful when space is limited.
What cell technology does JA Solar JAM54S40-455/LR use vs JA Solar JAT54S40-485/LR?
JA Solar JAM54S40-455/LR uses TOPCon cells; JA Solar JAT54S40-485/LR uses TOPCon. Modern n-type technologies (TOPCon, HJT, BC) typically deliver higher efficiency and lower degradation compared to older PERC (p-type) cells.
What is the warranty on JA Solar JAM54S40-455/LR and JA Solar JAT54S40-485/LR?
JA Solar JAM54S40-455/LR has a 30 years power warranty; JA Solar JAT54S40-485/LR has a 30 years power warranty. The power warranty guarantees a minimum percentage of rated output at the end of the warranty period (typically 80-87%). Product (materials) warranties are usually shorter.

Shop prices: See 389 JA Solar offers

Every figure here is from the manufacturers' own datasheets - a dash means the value is not published, never an estimate. The thirty-year projection and the temperature scenarios are calculations from those figures, and each states its assumption above.