Off-Grid Solar Setup: Step-by-Step DIY Guide With Diagram and Pictures

Last checked 20 October 2026 · JH Solar guide

What an off-grid solar setup is, and who it suits

In an off-grid solar setup, everything you use comes from the panels and the battery. During the day the panels charge the battery through a charge controller. At night, and on cloudy days, an inverter turns battery power into normal AC for your loads. If the battery runs low, the power stops until the sun comes back.

People look for this setup for three reasons: a place with no power line, frequent brownouts at home, or the wish to learn solar hands-on on a small budget. If you just want portable power for a few devices, a power station with a solar panel may be simpler, since the controller, battery and inverter come in one box.

The benefits are independence from the grid, no utility paperwork, and parts you can understand. The weaknesses: capacity is limited by the battery, several cloudy days can drain it, and an off-grid solar setup is not designed to run an aircon or a whole house.

The off-grid solar setup diagram

Here is the layout this guide follows. Orange lines are DC, navy lines are AC, and the green dashed line is grounding. If any symbol is new to you, our solar setup diagram hub explains each part and the color key in detail.

Solar panels feed a PV breaker, then an MPPT charge controller. The controller and the inverter both connect to the battery through one main fuse and busbar at the battery positive; the inverter branch also has a DC breaker near the battery. The inverter feeds an AC breaker and the household loads. The panel frames, controller, inverter and battery bond to a grounding rod.

Parts list for an off-grid solar setup, with the sizing rule for each

Do not buy by price or by the biggest number on the box. Each part has a sizing rule tied to your loads; the example column uses the worked example below.

LiFePO4 is the common chemistry for home solar batteries because it handles deeper daily cycling than lead-acid and usually comes with a built-in BMS. You can read more about lithium iron phosphate batteries or compare options in our solar battery guide.

Worked sizing example for a small off-grid solar setup

Example only: a farm rest house with lights, fans, phone charging and a small fridge, using the same method as our solar computation calculator.

• Battery. To cover one full day: 2.32 ÷ (0.80 × 0.90) = 3.22 kWh nominal. At 24 V, that is 3,222 ÷ 24 ≈ 134 Ah, so choose the next size up. For two cloudy days, double it to about 6.44 kWh.
• Panels. At 4 peak sun hours: 2.32 ÷ (4 × 0.75) = 0.77 kWp. With 400 W panels: 0.77 ÷ 0.40 = 1.93, round up to 2. At a rainy-season 3.5 hours: 2.32 ÷ (3.5 × 0.75) = 0.88 kWp, or 2.21 panels, so 3. The 400 W panel is only an example; our calculator starts at 620 W, which you can change.
• Charge controller. 3 × 400 W = 1,200 W ÷ 24 V = 50 A, so pick an MPPT rated for at least that and check its PV voltage limit against the panel datasheet.
• Inverter. Highest load at once: 40 + 100 + 40 + 100 W (fridge compressor running) = 280 W. A 1,000 W pure sine wave inverter leaves room, but confirm its surge rating covers the fridge start. Our solar inverter guide explains continuous and surge ratings.

Why 24 V and not 12 V? The same power at twice the voltage needs half the current, so the cables, fuses and breakers in an off-grid solar setup can be smaller and stay cooler.

Off-grid solar setup wiring order, step by step with pictures

The order matters as much as the parts. Keep every breaker open until the step that closes it, and do not skip the multimeter checks. Our panel mounting and installation guide has more on roof and rack mounting.

1. 1

   Step 1: Mount the panels and cover them

   Bolt the panels to a solid rack with the clamps the rack maker specifies. Cover them with a tarp: panels make voltage as soon as light hits them.

   

2. 2

   Step 2: Mount the controller, inverter and battery

   Fix the controller and inverter to a wall in shade, with the clearance the manuals ask for. Place the battery close by, off the floor and away from water, so battery cables stay short. Mount the breakers and fuse holder, all switched off.

3. 3

   Step 3: Ground and bond before anything carries power

   Bond each panel frame, the rack, and the controller and inverter grounding points to the ground rod, as the manuals show. Do this now, before any wire carries power.

4. 4

   Step 4: Fit the battery fuse, then connect the battery to the controller FIRST

   Fit the fuse holder on the battery positive cable, close to the terminal, fuse removed. Connect the controller battery terminals, check polarity, then insert the fuse. The controller should detect 12 V or 24 V.

   Why battery first? Most charge controllers need battery voltage to set themselves up. Panels first can confuse the system voltage, and some manuals warn it can damage the controller.

   

5. 5

   Step 5: Connect the panels to the controller through the PV breaker

   With the PV breaker open, wire panels to its input and its output to the controller. Uncover the panels, check voltage and polarity at the breaker, then close it and watch for charging.

6. 6

   Step 6: Connect the inverter through the DC breaker

   Inverter off, DC breaker open, run cables from the battery to the inverter input, with the DC breaker close to the battery end. If this cable does not pass through the main battery fuse, it needs its own fuse near the battery positive. Check polarity twice; reversed polarity can destroy an inverter. Close the breaker as the manual describes.

7. 7

   Step 7: Add the AC breaker on the inverter output

   Connect the inverter AC output to an AC breaker, kept open for now, or follow the manual for its built-in outlets.

8. 8

   Step 8: Connect the loads

   Plug lights, fans, chargers and the fridge into the inverter outlets or a heavy-duty extension with its own protection. Fixed wiring into walls and outlets is a job for a licensed electrician.

9. 9

   Step 9: Test everything with a multimeter

   Measure battery voltage, PV voltage at the controller and inverter AC output, and compare them with the displays. Then follow the checklist below.

   

Fuse and breaker placement

In an off-grid solar setup, every cable from a battery or panels needs protection at the source end. Use DC-rated fuses and breakers on the DC side; AC-only breakers may not break DC current safely.

Cable sizing: the principle, not a guess

Cable size depends on the current it carries and its length. Higher current and longer runs both need thicker copper, because resistance causes voltage drop: lost power, warm cables and an inverter that may shut off under load.

Use the cable maker's tables and the equipment manuals for your off-grid solar setup. Keep the battery-to-inverter run short, since it carries the most current, and use solar-rated cable outdoors. Never undersize: a thin cable is a fire risk.

Testing an off-grid solar setup: first switch-on checklist

Use this checklist for the first full switch-on, and again after any change to the wiring.

1. All breakers open, inverter off, fuse removed. Check every terminal is tight.
2. Measure battery voltage at its terminals; it should match the nominal 12 V or 24 V range in the manual.
3. Insert the battery fuse; confirm the controller detects the right system voltage.
4. Uncover panels; measure PV voltage and polarity at the PV breaker, then close it and confirm charging.
5. Close the DC breaker, switch on the inverter, and measure its AC output.
6. Close the AC breaker and add loads one at a time, starting small and ending with the fridge.
7. After an hour, touch the cable insulation near each terminal with the back of your hand, never bare metal; anything warm needs rechecking.

Maintenance for an off-grid solar setup

Clean the panels with water and a soft brush in the early morning when dust builds up. Each month, check that terminals are tight and cool, cables are not cracked or chewed, and the controller shows normal charging.

Keep the battery area clean, dry and ventilated, and do not let it sit flat for long. Flooded lead-acid needs water checks as the maker advises. Note the battery voltage on a few mornings each month; a slow drop is an early warning.

Common mistakes to avoid

Most problems in a DIY off-grid solar setup come from this short list.

• No battery fuse, or a fuse far from the battery.
• Connecting the panels before the battery.
• Using AC-only breakers on DC lines.
• Thin cable between battery and inverter, causing heat and shutdowns.
• An inverter too small for the fridge start-up surge.
• Mixing old and new batteries, or different chemistries.
• Skipping the ground rod and frame bonding.
• Plugging the inverter into a wall outlet to "feed" the house.

When to call a licensed electrician

Call a registered master electrician or professional electrical engineer for fixed AC wiring into walls, any link to your panel board or the grid, large battery banks, or high-voltage strings, and whenever something smells, sparks or gets hot. Our hybrid solar diagram guide shows what a grid-connected system involves. The Institute of Integrated Electrical Engineers (IIEE) publishes the Philippine Electrical Code that licensed practitioners follow.

Philippine conditions and phone tips

An off-grid solar setup here must survive typhoons, heat and long rainy seasons.

• Typhoons. Use through-bolts and rated clamps, a low and sturdy rack, and secure cable runs. Follow PAGASA tropical cyclone wind signals, and inspect the rack, bolts and cables after every storm.
• Heat around the battery. Batteries and inverters age faster in heat. Keep them in shade with airflow, never under a bare iron roof or in direct afternoon sun.
• Rainy-season cloudy days. Peak sun hours are typically about 3.5 to 5 a day; check your area on the Global Solar Atlas. For wet months, add battery or panel margin, as the example did.
• Brownouts. At home, a small off-grid circuit can keep lights, fans and phones running. Keep it fully separate from house wiring unless an electrician connects it properly.

On your phone

• Screenshot the diagram and the switch-on checklist so you can read them offline at the site.
• Photograph each connection before you close a cover, so you have a record of the wiring.
• Photograph the controller and inverter settings screens after setup, in case they reset.
• Keep a simple note of battery voltage readings to spot slow problems early.

Larger all-in-one units like those from JH Solar work with or without grid power and are installed by a licensed electrician; their hybrid layout is covered in our diagrams hub. For background, see this overview of solar charge controllers.

Conclusion: build it in order, test it, keep it safe

A small off-grid solar setup is a practical way to power a nipa hut, farm or brownout corner, and the DC side is within reach of a careful DIYer. Size each part from your own loads, follow the wiring order with the battery first, put a DC-rated fuse or breaker on every line, ground everything, and test with a multimeter before you trust it.

When the job grows into fixed AC wiring, a link to your panel board, or air conditioning, hand it to a licensed electrician.