RCD / GFCI — The Complete Guide
The RCD is the only device in your home that can save your life from electric shock. We'll explain it in the simplest possible terms, with real Egyptian market examples.
By the Ases Kahraba team · Last updated: March 2026
Quick Answer
The RCD monitors electrical current every moment — if it detects any leakage, even tiny (30 milliamps), it cuts power in under a second before anything bad happens. The Egyptian Electrical Code mandates it in bathrooms, kitchens, and all outdoor circuits.
Think of it this way — The Dead-Simple Explanation
Imagine electricity flows like water in two pipes — one going out, one coming back. In normal conditions, what goes out = exactly what comes back.
If there's a leak — like electricity taking a shortcut through a person's body — the return current will be less than what went out.
The RCD detects that difference and cuts power instantly — before the shock affects the heart or nervous system.
⚡ Real-life example:
A child in the bathroom touches a faulty water heater — without an RCD: serious shock. With a 30 mA RCD: power cut in less than 1/30th of a second.
The Three Types — What's the Difference?
RCCB
Basic residual current breaker — protects from earth leakage only. Must be combined with a separate MCB for overload protection.
RCBO
RCCB + MCB in one body — protects from leakage and overload together. Best for individual circuits.
GFCI
The American name for the same device. In Egypt we say RCCB or RCD. Exactly the same function.
Current Ratings — Which One Do I Choose?
Tiny bathrooms or locations where someone could be fully immersed in water. Rare in homes.
What the Egyptian Electrical Code mandates for bathrooms, kitchens, and pool surrounds. This is what you need in most cases.
Not sufficient to protect people from shock — but useful to reduce electrical fire risk on main lines.
Exactly Where Should You Install RCDs?
Bathroom
Mandatory per Egyptian Electrical Code
Kitchen
Mandatory (especially near the sink)
Pool surrounds
Mandatory — 30 mA maximum
Outdoors / Garden
Mandatory for all outdoor circuits
Bedrooms & Living rooms
Strongly recommended in new builds
Laundry room
Recommended (moisture + water + electricity)
Testing Your RCD — One Step Every Month
Every RCD has a small button labelled TEST. This isn't decorative — it tests whether your life-protection is actually working.
- Press the TEST button — the breaker must trip immediately.
- Reset the breaker back up and you're good.
- If it doesn't trip — the RCD is faulty and inactive. Replace it immediately.
⏰ How often?
Once a month is enough. Set a phone reminder.
Real Egypt Market Example — Gila Electric
Gila Al-Tawakol Electric — 45+ years in the Egyptian market, ISO TUV certified
Schneider Electric Resi9 RCCB
2-Pole · 25A · AC type · 30mA · 4.5kA breaking capacity
Model: R9R51225
~2,467 EGP
3,916 EGP
37% off
Ideal use
Residential bathrooms & kitchens
Trip speed
< 30 milliseconds
Availability
In stock — 72hr delivery
Why Schneider Resi9? — Schneider is the globally certified brand used widely in Egypt. Resi9 is the residential line designed specifically for homes and apartments. Gila Electric is an authorized ISO TUV-certified dealer with 7 locations across Egypt.
Common Mistakes — Don't Do These!
- 1
Using 100 mA RCD in bathrooms
Not enough for life safety — bathrooms require 30 mA.
- 2
Never pressing the TEST button
An RCD can fail internally without any visible sign. Monthly testing is the only way to know.
- 3
Bypassing the RCD after repeated tripping
Each trip = a real alarm. The right solution: find the leakage source, don't disable the protection.
- 4
Relying on one RCD for the whole home
When it trips — the whole house goes dark. Better: one RCD per circuit group.
Frequently Asked Questions
Is one RCD for the whole home enough?
A single main-entry RCD cuts all power when any leakage is detected — meaning everything goes off even if the problem is in just one circuit. Better: separate RCDs for circuit groups (bathrooms, kitchen) so a fault is isolated without affecting the rest of the home.
What's the difference between RCD and MCB?
MCB (miniature circuit breaker) protects from overload and short circuit — like if you plug too many appliances into one socket. RCD protects from earth leakage — like if electricity starts flowing through your body. RCBO does both in one unit. Modern homes need both.
Does a 30 mA RCD completely prevent electric shock?
It greatly reduces risk but not 100%. It cuts power in under a second (~30 ms) — fast enough to prevent death in most cases. The tiny amount that passes before the trip may feel like a mild tingle.
Why does my RCD keep tripping with nothing obvious happening?
That's not a fault in the RCD — that's the RCD doing its job and detecting real leakage. The source may be: moisture in an outlet, aging wire insulation, a faulty appliance, or the water heater leaking internally. Every trip = a real problem that needs a technician.
How much does an RCD cost in Egypt?
A quality RCCB like the Schneider Resi9 available at Gila Electric starts around EGP 2,500. Installation costs an additional EGP 100–300. A small investment compared to the protection it gives your family.