Complete Generator and ATS Guide
With Egypt's recurring power outages, a backup generator has become a necessity for villas and businesses. But the real danger isn't the generator itself — it's incorrect wiring. This guide explains how to choose the right generator and install an ATS switch safely.
By the Ases Kahraba team — Last updated: March 2026
Quick Answer
A 5kVA generator covers a typical Egyptian apartment — ATS switches in seconds automatically. How to size it right, installation cost, and earthing requirements for 2026.
Key Topics in This Guide
- Generator sizing for Egypt: summer outages typically last 1–3 hours on a repeating cycle — size for essential loads only (lighting + one room AC + refrigerator + water pump). General rule: total kW × 1.25 = generator capacity. A 3-bedroom villa typically needs 5–8 kVA.
- ATS (Automatic Transfer Switch): automatically switches from grid to generator on power failure and back when grid is restored. Types: 2-pole (single-phase) or 4-pole (three-phase). Never connect a generator without an ATS or a properly isolated manual changeover switch.
- Generator earthing: the generator must be separately earthed and also bonded to the building's earthing system. Missing earthing = risk of electric shock from metallic generator parts.
- Installation location: generators run on diesel or petrol — must be installed outdoors or in a room with excellent ventilation due to carbon monoxide. Minimum safe distance ≥ 3 m from windows and doors.
- Fatal mistakes: connecting the generator directly to the panel without an ATS (causes dangerous backfeed to utility workers), and running the generator indoors or in the garage.
- Inverter generators: quieter, more fuel-efficient, and safe for sensitive electronics (computers, TVs). Conventional generators are cheaper and more powerful but noisier.
- Periodic maintenance: change oil every 100 running hours, check battery monthly, and run the generator under light load for 15 minutes weekly to maintain engine performance.
Frequently Asked Questions
Can I install an ATS myself or does it need a specialist?
ATS installation requires a licensed electrician — wiring errors can cause dangerous backfeed that injures utility workers repairing the grid. This is one job where safety is non-negotiable.
What's the difference between ATS and a Manual Transfer Switch?
ATS works automatically without human intervention — the generator starts and power transfers within 10–30 seconds. A manual transfer switch requires someone to physically flip the switch. ATS is more expensive but safer and more convenient for daily use.
How long does the ATS internal battery last?
The ATS itself doesn't use a battery — it's an automatic switch. The battery you're thinking of is the generator's starter battery. This battery starts the generator and needs periodic charging and replacement every 2–3 years.
Can the generator run a split AC?
Yes, but calculate carefully. A 1.5 HP AC draws ~10 A running current plus higher startup current. A 3 kVA generator can handle one AC plus lighting. For multiple ACs, you need a larger generator or start ACs sequentially to avoid startup load peaks.
What does generator + ATS installation cost for a Cairo villa?
ATS installation alone (excluding the generator) costs EGP 3,000–8,000 depending on type and capacity. The generator itself is separate (EGP 5,000–30,000 depending on size and brand). Contact us for a comprehensive quote.
Egypt has scheduled power cuts — is a generator better than a UPS?
It depends on outage duration: a UPS (battery + inverter) suits outages under one hour — covering a computer, basic lighting, and router only, at EGP 3,000–8,000 for a home system. A generator is necessary for longer outages (1–3+ hours) when you need AC and refrigerator running. The optimal Egypt solution: UPS for the workstation and lighting + a small generator for AC and refrigeration.
What are the best generator brands available in Egypt 2026?
For residential and villa use: Cummins and Perkins (highest quality, higher cost) — Hyundai and Yamaha (mid-range, reliable) — Kipor and generic Chinese brands (cheapest, acceptable for infrequent use). Avoid unbranded Chinese generators with no warranty or spare parts availability in the Egyptian market.