Woman sitting on a couch using a torch to read in a dark home during load shedding in South Africa, highlighting the need for a reliable inverter setup

Load Shedding Inverter Setup: Complete Installation Guide 2026

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Introduction 

Load shedding is still part of daily life in South Africa, and for many households, an inverter system has become essential rather than optional. Whether you are working from home, running a small business or simply trying to keep food fresh and lights on, a properly installed inverter setup makes a huge difference. 

Professional installations can be expensive, but the good news is that a technically confident homeowner can handle a large part of the process. The key is knowing where DIY is safe and where a qualified electrician must step in, especially for final connections and issuing a Certificate of Compliance (COC). 

In this guide, you will learn how to plan, size and install a typical load shedding inverter system step by step. We will cover battery sizing, wiring basics, changeover switches, testing and compliance so you can build a system that is safe, reliable and ready for future upgrades. 

 

Pre-Installation Planning & Sizing 

Before touching tools or wiring, take time to plan your system properly. This step determines how well your inverter will perform during outages. 

Calculate Power Requirements 

Start by listing your essential loads. This usually includes your WiFi router, a few LED lights, a fridge, TV and possibly laptops. 

Add up the wattage of each item to get your total load. Then add a 20% safety margin: 

Minimum inverter size = Total watts × 1.2 

For example, a 500W load needs at least a 600W inverter, which typically means choosing an 850VA unit or higher. 

Choose Inverter Type 

Not all inverters are equal. Your choice here affects performance, efficiency and appliance safety. Read our guide on pure vs modified sine wave inverters to understand the difference before you buy. 

Pure sine wave inverters are the best option for most homes. They safely power fridges, TVs and sensitive electronics. Modified sine wave inverters are cheaper but can cause noise, overheating or damage in some devices. 

For most homes: 

  • 1.5kVA suits basic essentials 
  • 3kVA suits average households 
  • 5kVA suits larger homes or heavier usage 

Battery Bank Sizing 

Your battery determines how long your system runs during load shedding. 

A practical formula is: 

Runtime (hours) ≈ (Battery Ah × Voltage × 0.8) ÷ Load (W) 

The 0.8 accounts for losses and safe discharge limits. 

Typical expectations: 

  • 200Ah: 4–6 hours 
  • 400Ah: 8–12 hours 
  • 600Ah+: 12+ hours 

Choose: 

  • 12V for small systems 
  • 24V for mid-range 
  • 48V for larger setups 

Tools & Materials 

Having the right tools makes installation safer and easier. 

You will need: 

  • Multimeter 
  • Crimping tool and wire stripper 
  • Drill and mounting hardware 
  • DC cables (25mm²–50mm² depending on system) 
  • AC cable (2.5mm²–4mm²) 
  • Changeover switch or automatic transfer switch 
  • DC fuse or breaker 
  • Safety gear (gloves, eye protection) 

 

Step-by-Step Installation Process 

Now that planning is done, you can move into the physical installation. Take your time and double-check each step. 

Step 1: Install Inverter 

Choose a cool, dry and well-ventilated area such as a garage or utility room. Avoid direct sunlight and damp spaces. 

Mount the inverter securely on a wall using proper anchors. Leave enough space around it for airflow and maintenance. 

Good airflow prevents overheating and improves efficiency. 

 

Step 2: Position & Wire Battery Bank 

Battery placement is critical for safety and lifespan. 

Place batteries: 

  • In a ventilated area 
  • On a non-metal surface 
  • Away from heat and moisture 

Wiring basics: 

  • Series increases voltage 
  • Parallel increases capacity 

Keep all cables equal length and thickness to ensure balanced performance. 

 

Step 3: Install Changeover Switch 

The changeover switch controls whether your home runs on Eskom or inverter power. 

You can choose: 

  • Manual switch (cheaper) 
  • Automatic transfer switch (more convenient) 

Install it near your DB board and clearly label positions: 

  • Eskom 
  • Inverter 
  • Off 

This step is essential to prevent backfeeding, which is dangerous and illegal. 

 

Step 4: Connect Inverter to Batteries (CRITICAL) 

This is one of the most important steps, so work carefully. 

Before starting: 

  • Switch everything OFF 
  • Install a DC fuse near the battery 

Connection order: 

  1. Connect negative cable 
  1. Connect positive cable through fuse 

Always check polarity with a multimeter before switching on. Reversed polarity can destroy your inverter instantly. 

 

Step 5: AC Wiring to Distribution Board 

This is where your inverter connects to your home circuits. 

Identify essential circuits such as: 

  • Lights 
  • Fridge 
  • TV and router plugs 

Install: 

  • Input breaker (grid to inverter) 
  • Output breaker (inverter to loads) 
  • RCD protection where required 

All wiring must comply with South African standards. 

This is typically where a qualified electrician should step in if you are unsure. 

 

Testing & Commissioning 

Once everything is connected, testing ensures your system works safely and correctly. 

Pre-Power Checks 

Before switching on: 

  • Check all connections are tight 
  • Ensure no exposed wires 
  • Confirm correct polarity 

Use a multimeter to verify voltage and continuity. 

 

Initial Power-Up 

Turn on the battery first, then the inverter. 

Check: 

  • Display readings 
  • Output voltage (220–230V) 
  • No error codes 

Test the changeover switch to ensure correct operation. 

 

Load & Runtime Testing 

Start small and increase gradually. 

Monitor: 

  • Voltage drop 
  • Temperature 
  • Load levels 

Simulate a power outage to confirm everything switches correctly. 

 

Battery Charging Configuration 

Correct charging settings are essential for battery life. 

Typical values: 

  • Float: 13.5–13.8V (12V system) 
  • Bulk: 14.4–14.6V 

Charging current should be about 10–20% of battery capacity. 

Incorrect settings will shorten battery life significantly. 

 

Safety, Compliance & Maintenance 

Safety is not optional. This is where many DIY setups go wrong. 

Electrical Safety Standards 

All installations must follow SANS 10142-1. 

This includes: 

  • Correct cable sizes 
  • Proper earthing 
  • Safe isolation points 

These rules protect your home and ensure legal compliance. 

 

Certificate of Compliance (COC) 

Any fixed installation must be signed off by a registered electrician. 

They will check: 

  • Wiring quality 
  • Earthing 
  • Protection devices 
  • System operation 

Without a COC, you risk insurance issues and legal problems. 

 

Fire & Chemical Safety 

Battery systems carry real risks if not handled properly. 

Always: 

  • Install a fire extinguisher nearby 
  • Ensure proper ventilation 
  • Keep sparks and flames away 

For lead-acid batteries, be prepared for acid spills. 

 

Maintenance Schedule 

Regular checks keep your system running efficiently. 

Weekly: 

  • Visual inspection 

Monthly: 

  • Check voltage and connections 

Annually: 

  • Full inspection and testing 

 

Troubleshooting & Upgrades 

Even good systems need adjustments over time. 

Common Issues 

Short runtime: 

  • Battery too small or old 

Inverter not turning on: 

  • Fuse or wiring issue 

Overload alarms: 

  • Too many appliances 

 

System Upgrades 

You can expand your system over time. 

Options include: 

  • Adding more batteries 
  • Upgrading inverter size 
  • Adding solar panels 

Plan ahead so upgrades are easy and cost-effective. 

 

Cost Breakdown & ROI 

Understanding cost helps you decide how far to go with your setup. 

DIY vs Professional 

DIY can save: 

  • R2 000–R5 000 depending on system 

But professional installs offer: 

  • Warranty support 
  • Compliance 
  • Peace of mind 

 

ROI Calculation 

Savings come from: 

  • Avoided food spoilage 
  • Continued work productivity 
  • Reduced generator use 

Most mid-range systems pay for themselves within 1–2 years in real-world value. 

 

Frequently Asked Questions 

Do I need an electrician? 

Yes for any system connected to your DB. DIY is fine for portable setups only. 

Can I run a geyser? 

Not realistically on small systems. It requires a large inverter and battery bank. 

How long do batteries last? 

  • Lead-acid: 3–5 years 
  • Lithium: 8–15 years 

UPS vs inverter? 

UPS is instant and for sensitive electronics. 

Inverters handle larger loads for longer. 

 

Conclusion 

Installing an inverter system for load shedding is one of the most practical upgrades a South African homeowner can make. With proper planning, careful wiring and respect for safety standards, a DIY-assisted setup can save money while still delivering reliable backup power. 

Focus on getting the basics right: correct battery sizing, safe wiring and a properly configured changeover system. Start small if needed, but choose equipment that allows you to expand later. 

Most importantly, never compromise on safety or compliance. A system that is correctly installed and certified will protect not just your appliances, but your home and family as well.