Solar Panels With Bypass Diodes
This graph shows the positive effect of bypass diodes with clouds and leafy shade. There are 3 30V (about) serial panels with 3 bypass diodes each which results in each bypass diode controlling about 10V of panel output.
The morning starts with overcast clouds and full solar panel array voltage output (about 90V) in the limited light.
At 8:37 the clouds departed leaving leafy shade covering the panels resulting in 6 bypass diodes conducting and 3 of the panel sections producing power at 30V. As the shade changes on the panels the panel voltage increases to 40, 50, 60 and 70V.
At 9:27 all of the shade is off of the panels and the panel voltage is 90V. The MPPT controller continues to optimize the panel output as the sun continues to rise.
The panels are flat mounted and the sun is rising.
Note: Bypass Diodes have the effect of 9 independent serial panel sections. When there is a shadow on one section that section is bypassed – ie the effect is like a short for that section and it bypasses the amps of the other sections. One bypassed section results in 8/9 of the voltage, two sections in 7/9 of the voltage, etc, however the panel amps are not effected. I’ve seen charging with only 2 sections or 20V. Bypassed sections do not have to be in the same physical panel.
The morning starts with overcast clouds and full solar panel array voltage output (about 90V) in the limited light.
At 8:37 the clouds departed leaving leafy shade covering the panels resulting in 6 bypass diodes conducting and 3 of the panel sections producing power at 30V. As the shade changes on the panels the panel voltage increases to 40, 50, 60 and 70V.
At 9:27 all of the shade is off of the panels and the panel voltage is 90V. The MPPT controller continues to optimize the panel output as the sun continues to rise.
The panels are flat mounted and the sun is rising.
Note: Bypass Diodes have the effect of 9 independent serial panel sections. When there is a shadow on one section that section is bypassed – ie the effect is like a short for that section and it bypasses the amps of the other sections. One bypassed section results in 8/9 of the voltage, two sections in 7/9 of the voltage, etc, however the panel amps are not effected. I’ve seen charging with only 2 sections or 20V. Bypassed sections do not have to be in the same physical panel.
