800W 12V Off-Grid Solar Wiring Diagram Complete (2S2P)
Computed 800W 12V off-grid solar system solar diagram: 2S2P array, wire gauges, OCPD, battery arrangement, routed parts and printable files.
View the scalable diagram inline
What this computed plan shows
Built around a 800 W array, the 800W 12V Off-Grid Solar Wiring Diagram Complete (2S2P) is a computed answer to the demand phrasing “off grid solar system diagram.” The diagram shows 4 modules as 2S2P, not an unspecified bank of panels, and it carries 48 Voc plus 20 operating amps into the controller review. Every table on this page describes that same state.
The MPPT controller needs at least 84 A of output capacity. Its PV input must also remain above the engine’s 60 V cold-design check, while the configured ceiling is 150 V. That margin matters because the diagram’s 48 V nameplate value is not the final controller comparison value.
The array-to-controller route is 21 ft one way and carries 32.8 design amps. It resolves to 8 AWG copper, a 35 A OCPD and 2.68% calculated drop. Downstream, the 10 ft controller lead uses 2 AWG copper behind 90 A protection, holding its computed drop to 2.16%.
A 1S1P layout keeps every battery in a complete 12 V string. Using 1 LiFePO₄ units at 100 Ah each yields 100 bank amp-hours and 1,280 nominal watt-hours. Parallel paths still need equal cable geometry, suitable disconnecting means and manufacturer-approved protection.
The battery-to-inverter path is only 5 ft, but it carries 148.1 A continuously in the calculation. That combination selects 250 kcmil copper and 200 A protection while retaining 0.64% drop. The 3,200 W surge figure should be compared with motor or compressor starting loads separately from continuous power.
Use the parts links as a routed specification checklist, not permission to substitute unlike ratings. Before buying, confirm controller voltage, breaker interrupt rating, conductor insulation, terminal temperature class, battery series approval and inverter DC range. The customizer carries this exact 800W 12V Off-Grid Solar Wiring Diagram Complete (2S2P) state in its URL hash so run lengths or nameplate values can be changed without editing the static drawing.
For later comparison, keep the 800 W array, 1S1P bank and the 21/10/5 ft one-way routes together when requesting equipment quotes or an inspection review.
Wire, protection and battery schedules
Wire schedule
| Segment | Design current | One-way run | Computed conductor | Voltage drop | Sizing basis |
|---|---|---|---|---|---|
| array → controller | 32.8 A | 21 ft | 8 AWG copper | 2.68% | 156% of array Isc (NEC 690.8) |
| controller → battery | 66.7 A | 10 ft | 2 AWG copper | 2.16% | controller output at 125% continuous-load ampacity |
| battery → inverter | 148.1 A | 5 ft | 250 kcmil copper | 0.64% | inverter continuous DC input at 90% efficiency and 125% ampacity |
Overcurrent protection
| Protected segment | Required ampacity | OCPD | Conductor ampacity | Verdict |
|---|---|---|---|---|
| array → controller | 32.8 A | 35 A | 40 A | within |
| controller → battery | 83.3 A | 90 A | 95 A | within |
| battery → inverter | 185.2 A | 200 A | 215 A | within |
Battery arrangement
| Arrangement | Chemistry | Units | Unit capacity | Bank capacity | Nominal energy | Nominal voltage |
|---|---|---|---|---|---|---|
| 1S1P | LiFePO₄ | 1 | 100 Ah | 100 Ah | 1,280 Wh | 12 V |
Static routed parts list
Parts are computed from this passing configuration. A route appears only when the verified catalogue record proves every displayed numeric rating; all uncertain matches stay local for verification. Routed links may earn Off Grid Authority a commission at no extra cost to you.
Pre-install review steps
- Confirm the array and controller window: Verify that the 2S2P string plan produces 48 V open circuit and that the equipment is rated above the 60 V cold-design value.
- Lay out the protected DC runs: Measure the one-way paths before ordering cable, then compare them with the computed 21 ft, 10 ft and 5 ft runs shown here.
- Build complete battery strings: Arrange all 1 battery units as 1S1P; do not leave a partial series string in a 12 V bank.
- Commission against equipment instructions: Check polarity, terminal torque, DC interrupt ratings, conductor temperature ratings, ambient correction and local inspection requirements before energizing the 1,600 W inverter.
Customize or compare
Open the parent build guide for the surrounding design context, safety notes and installation discussion.