A generator changeover switch is the safe, legal way to connect a portable or standby generator to your house wiring. It is a three position switch, mains, off and generator, mounted beside the distribution board, so the house can only ever be on one source at a time. Send GeneratorRepair.co.za a single request and independent registered electricians in your area quote you directly. We do not do electrical work ourselves, and the request is free with no obligation. A manual changeover switch is the cheapest option when you are home to start the generator yourself.
Why a generator changeover switch matters
Plugging a generator into a wall socket with a double-ended lead, a so-called suicide lead, puts generator voltage on exposed pins and back-feeds the street. Transformers step that 230 V up to thousands of volts on the line, where municipal or Eskom linesmen may be working during load-shedding or after cable theft. A proper changeover switch with a break-before-make action makes back-feeding impossible, and it protects the generator when the mains returns.
Manual changeover switch options
- Whole house: a rotary changeover on the main supply, with heavy loads such as geysers and stoves switched off by hand or by a separate breaker
- Essential circuits: lights, plugs, the fridge and gate motor moved onto a small essential board fed through the changeover, which suits 3 to 8 kVA sets
- Interlock kits: a mechanical slide that stops the main and generator breakers both being on
- Inlet socket: a weatherproof industrial inlet on the outside wall, so the generator stays outside with a proper extension lead
If you want the generator to start by itself, see the automatic transfer switch page.
Generator and inverter combinations
Many South African homes run a battery inverter for short outages and a generator for long ones. The generator usually feeds the inverter's AC input through the changeover or directly, so it charges the batteries and runs the house at the same time. Small generators can struggle with an inverter's charging load, and some inverters reject the rough output of open-frame sets, which is where inverter generators help. The electrician must also respect the inverter's neutral and earth bonding rules.
Cost, CoC and what to expect
As a guide, a manual generator changeover switch with an inlet socket supplied and fitted costs R2,800 to R7,500 for a single phase house. A separate essential circuits board adds R3,000 to R8,000, and three phase manual changeovers cost R6,000 to R20,000. Most installs take half a day. The electrician must be registered and issue a Certificate of Compliance under SANS 10142-1, and the job fits neatly into a wider generator installation.
What to include in your request
- Give the generator kVA and fuel type
- Say whether you want whole house or essential circuits
- Send a photo of the distribution board
- Mention any inverter or battery system
- Say where the generator will stand outside
Generator Changeover Switch for different sites
- Homes: a rotary changeover and outside inlet so the petrol generator runs lights, plugs and the fridge
- Estates and complexes: a changeover per unit where body corporate rules allow small quiet generators
- Farms and smallholdings: a manual changeover on the farmhouse and borehole pump for long rural outages
- Shops, offices and restaurants: an essential circuits board on a changeover for tills, lights and the alarm
- Factories, mines and sites: three phase manual changeovers for site offices, workshops and hired generators
- Lodges, venues and events: a changeover at a guesthouse or venue so a hired generator connects safely
- Clinics, schools and towers: a manual changeover at a church, school hall or small clinic with a portable set
Frequently asked questions
Is GeneratorRepair.co.za an electrical contractor?
Can I fit a changeover switch myself?
What size generator do I need for a changeover switch?
Do I still need to switch circuits off at the board?
Generator Changeover Switch by province and city
- Johannesburg
- Pretoria
- Centurion
- Midrand
- Sandton
- Randburg
- Roodepoort
- Krugersdorp
- Randfontein
- Germiston
- Boksburg
- Benoni
- Kempton Park
- Alberton
- Vanderbijlpark
- Vereeniging
- eMalahleni (Witbank)
- Middelburg
- Secunda
- Mbombela (Nelspruit)
- Rustenburg
- Brits
- Klerksdorp
- Potchefstroom
- Mahikeng
- Polokwane
- Tzaneen
- Kimberley
- Upington
- Bloemfontein
- Welkom
- Sasolburg
- Durban
- Pinetown
- Pietermaritzburg
- Richards Bay
- Newcastle
- Ladysmith
- Gqeberha (Port Elizabeth)
- East London
- Kariega (Uitenhage)
- Mthatha
- Cape Town
- Bellville
- Paarl
- Stellenbosch
- George
- Worcester