Enter your panel specs and MPPT controller — get the correct wiring configuration with compatibility check.
Panel Specifications
Find these values on your panel's datasheet or label (STC ratings).
Highest voltage, no load
Voltage at peak output
Highest current, shorted
Current at peak output
MPPT Controller
Max Voc
100V
Min Voc
5V
Max Isc
30A
Max Power
440W
Recommended: Series (4S × 1P)
4 × 200W panels → 800W array · 82.0V Vmp · 9.8A Imp
Array Voc
97.2V
max 100V
Array Vmp
82.0V
min 5V
Array Isc
10.2A
max 30A
Array Imp
9.8A
output current
Total Power
800W
MPPT 440W
Wiring
4S×1P
Array power (800W) exceeds MPPT rated power (440W) — controller will clip output. Not harmful but you're leaving power on the table.
This configuration is compatible with your MPPT controller.
Array Voc
24.3V
max 100V
Array Vmp
20.5V
min 5V
Array Isc
40.8A
max 30A
Array Imp
39.0A
output current
Total Power
800W
MPPT 440W
Wiring
1S×4P
Array Isc (40.8A) exceeds MPPT max input current (30A)
Array power (800W) exceeds MPPT rated power (440W) — controller will clip output. Not harmful but you're leaving power on the table.
More than 3 strings in parallel — consider a combiner box with string fuses for safety.
Array Voc
48.6V
max 100V
Array Vmp
41.0V
min 5V
Array Isc
20.4A
max 30A
Array Imp
19.5A
output current
Total Power
800W
MPPT 440W
Wiring
2S×2P
Array power (800W) exceeds MPPT rated power (440W) — controller will clip output. Not harmful but you're leaving power on the table.
This configuration is compatible with your MPPT controller.
How to wire it
Connect the positive (+) of panel 1 to the negative (−) of panel 2, and so on in a chain. The first panel's negative and last panel's positive connect to the MPPT. Voltage adds up, current stays the same.
Key rules
Never exceed your MPPT's max Voc — even briefly on a cold morning. Voc rises ~0.3%/°C as temperature drops.
Series wiring adds voltage, keeps current the same. Better for long cable runs (less current = less loss).
Parallel wiring keeps voltage the same, adds current. Needs heavier cable but tolerates partial shading better.
Always fuse each parallel string at the panel end — a short in one string can backfeed through others.
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