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390/MR/1000V vs 370/MR/1000V 14 of 19 identical Swap Change panels

JA Solar JAM60S21-390/MR/1000V vs JA Solar JAM60S21-370/MR/1000V

JAM60S21-390/MR/1000V
390 Wp 21.00 % PERC
Open panel page Datasheet PDF
VS
JAM60S21-370/MR/1000V
370 Wp 19.90 % PERC
Open panel page Datasheet PDF
The verdict

390/MR/1000V leads on the differences that matter

The largest is module efficiency: 1.10 pp more efficient. 14 of 19 comparable parameters are identical.

See all 5 differences
How alike are they
14 of 19 comparable
parameters are identical
identical differs
01

What actually differs

5 of 19 parameters
Parameter 390/MR/1000V 370/MR/1000V Difference
Module efficiency 21.00 % 19.90 % 1.10 pp more efficient
Power density 209.6 Wp/m² 198.8 Wp/m² 10.7 Wp/m² higher
Rated power 390 Wp 370 Wp 20 W more power
Weight per kWp 48.2 kg/kWp 50.8 kg/kWp 2.6 kg/kWp lighter
Voltage at max power 35.33 V 34.23 V 1.10 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
Same temp coeff. for both panels (-0.350 %/°C), so a warmer roof scales both curves by the same factor: the totals fall together and neither panel gains on the other.
390/MR/1000V
12,640 kWh
370/MR/1000V
11,991 kWh
Lifetime gap
649 kWh
Output when it is hot
Rated power carried across the range a module actually sees
Scenario 390/MR/1000V 370/MR/1000V
Standard test conditions 25 °C 100.0% of rated power 390 W 370 W
Cool, bright day 40 °C 94.8% of rated power 370 W 351 W
Typical summer roof 55 °C 89.5% of rated power 349 W 331 W
Hot roof 70 °C 84.2% of rated power 329 W 312 W
03

Full specification

Parameter 390/MR/1000V 370/MR/1000V Difference
Power and efficiency
Rated power 390 Wp 370 Wp +20 W for 390/MR/1000V
Module efficiency 21.00 % 19.90 % +1.10 pp for 390/MR/1000V
Power density 209.6 Wp/m² 198.8 Wp/m² +10.7 Wp/m² for 390/MR/1000V
Open-circuit voltage 41.94 V 41.30 V Effectively the same
Voltage at max power 35.33 V 34.23 V 1.10 V apart
Short-circuit current 11.58 A 11.35 A Effectively the same
Current at max power 11.04 A 10.81 A Effectively the same
Temperature
Temperature coefficient -0.350 %/°C -0.350 %/°C Same
Mechanical
Dimensions 1769x1052x30 mm 1769x1052x30 mm Same
Module area 1.861 m² 1.861 m² Same
Weight 18.8 kg 18.8 kg Same
Weight per kWp 48.2 kg/kWp 50.8 kg/kWp -2.6 kg/kWp for 390/MR/1000V
Warranty and degradation
Product warranty 12 yrs 12 yrs Same
Performance warranty 25 yrs 25 yrs Same
Annual degradation 0.55 %/yr 0.55 %/yr Same
Technology
Cell technology PERC PERC Same
Cell type Monocrystalline Monocrystalline Same
Cell count 120 120 Same
Bifacial No No Same
04

Against the whole database

14,129 panels
Efficiency
#9,828 vs #12,416
390/MR/1000V leads by 2,588 places
Power density
#10,005 vs #12,431
390/MR/1000V leads by 2,426 places
Heat behaviour
#10,489 vs #10,489
Tied - the same position in the database
Weight
#2,106 vs #4,243
390/MR/1000V leads by 2,137 places
Warranty
#9,912 vs #9,912
Tied - the same position in the database
Overall
#12,055 vs #12,666
390/MR/1000V leads by 611 places
05

More useful comparisons

Open the full database
Same series, other bin
JA Solar JAM60S21-390/MR/1000V vs JA Solar JAM60S21-385/MR/1000V
One difference: module efficiency
Same series, other bin
JA Solar JAM60S21-390/MR/1000V vs JA Solar JAM60S21-380/MR/1000V
3 differences, the largest is module efficiency
Same series, other bin
JA Solar JAM60S21-390/MR/1000V vs JA Solar JAM60S21-375/MR/1000V
3 differences, the largest is module efficiency
Same series, other bin
JA Solar JAM60S21-390/MR/1000V vs JA Solar JAM60S21-365/MR/1000V
5 differences, the largest is module efficiency
Same manufacturer
JA Solar JAM60S21-390/MR/1000V vs JA Solar JAM66D46-740/LB
17 differences, the largest is module efficiency
Same manufacturer
JA Solar JAM60S21-390/MR/1000V vs JA Solar JAM66D46-735/LB
17 differences, the largest is module efficiency
06

Written summary

07

Questions about this pairing

Which panel is better: JA Solar JAM60S21-390/MR/1000V or JA Solar JAM60S21-370/MR/1000V?
According to our database: JA Solar JAM60S21-390/MR/1000V has higher module efficiency (21.00% vs 19.90%). See the full spec comparison and 30-year energy simulation above for a complete picture.
What is the efficiency of JA Solar JAM60S21-390/MR/1000V and JA Solar JAM60S21-370/MR/1000V?
JA Solar JAM60S21-390/MR/1000V has a module efficiency of 21.00%, while JA Solar JAM60S21-370/MR/1000V is 19.90%. Higher efficiency means more electricity from the same roof area - useful when space is limited.
What cell technology does JA Solar JAM60S21-390/MR/1000V use vs JA Solar JAM60S21-370/MR/1000V?
JA Solar JAM60S21-390/MR/1000V uses PERC cells; JA Solar JAM60S21-370/MR/1000V uses PERC. 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 JAM60S21-390/MR/1000V and JA Solar JAM60S21-370/MR/1000V?
JA Solar JAM60S21-390/MR/1000V has a 25 years power warranty; JA Solar JAM60S21-370/MR/1000V has a 25 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 330 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.