HCLH040 A Real-World Look at RCCBs

The anxiety of pressing that test button the first time was not nothing. Would they work? Was it a false sense of security under which we lived? The sense of relief I felt when I heard that comforting click was enormous, but it led to a more fundamental question: did these old units have my modern home filled with LED bulbs, smart gadgets, and an EV charger’s back?

This ordeal led me into a rabbit hole of research, talking with various electricians and eventually upgrading my home’s electrical protection system. Here’s what I discovered about RCCBs and what you should do for your own.

Deciphering the Discrepancy: Type AC vs Type A (and Type F)

Understanding RCCB types is like going from a mono TV set to 4K -- you don’t know what you’re missing until you get there. Here are the significant differences that I have been able to chart out:

Type AC RCDs are the old soldiers of electrical protection. They sense those AC residual currents — the classic sine wave faults widespread in older equipment. Consider them the dependable old guard, ideal for basic lighting circuits and straightforward appliances, such as those lacking electronic controls.

Type A is the current norm for RCCBs. They register everything Type AC does and the pulsing DC currents that contemporary electronics give off. Your washing machine’s variable speed motor, LED dimmer switches, and that new induction cooktop all do this and create a d.c. (direct current) component that can “blind”* Type AC devices. Australia’s AS/NZS 3000 amendment 2 (April 2023) mandates Type A protection for most new installs.

Type F RCDs take a step further to deal with composite currents and higher frequency disturbances. They are essential for delicate devices like medical equipment or precision electronics.

I like this analogy: Type AC is analogous to having a smoke detector that only alarms wood fires, while Type A alarms with wood and electrical fires. Today’s homes require both.

Why Now? Why the Trend? And Recent Rule Changes

MAY 9, 2025 By Chris Gandy

Recent Rules Changes (Addressing the Snowplough Handcuff)

The world of electricity has been quietly changing, and now regulations are catching up. Recent wiring standard changes in Australia now require Type A protection on all socket outlets supplying circuits, rendering Type AC redundant for new work. The European Union introduced similar requirements in 2019, and there was a trickle of other countries following suit.

As a homeowner, this has two implications: If you are renovating or adding circuits, that Type A device is what you’ll require. Second, although you can keep existing Type AC installs (for now), it does make sense to upgrade proactively, given how much modern electronics populate our homes.

I recently spoke with some local electricians, who saw increasing instances of nuisance tripping in older Type AC devices as homeowners retrofit their homes with smart home systems, electric vehicle chargers and more energy-efficient appliances. The die is cast — Type A is the new normal.

Balancing Expense and Security: Choosing the Ideal Tool

Budget was a question when I decided to upgrade my home safeguard. I looked up three classes of RCCBs:

Budget option ($45-60): Standard manufacturing Type A units. They are up to your current standards but do not have some of the more advanced features (surge indication, better durability ratings, etc).

Middle of the road ($80-120): What I eventually went with. These have higher build quality, clear trip indicators, and many have other safety features, including better short-circuit protection.

High-end models ($150+): Professional-grade units with better diagnostics, higher breaking capacity, and more extended warranties.

My go-to example: I was about to buy some of the budget ones and took them back after reading reviews about the inconsistent trip time. I paid a little over $20 more for the midrange one per unit, and it was money well spent when last week my EV charger tripped cleanly in a thunderstorm, protecting both itself and the onboard electronics of my car.

Actual Installations: Examples from Home and Industry

Case Study 1: Home D-I-Y Replacement

My kitchen circuit’s RCCB took me 2 hours to swap out and threw up a surprise – the original installation didn’t allow for the right In-Wall for my new induction cooktop. The type A device I put in made a stink right away due to super sensitive detection, and I ended up doing a proper wire upgrade. Total cost: $180 for the RCCB and $300 for rewiring, but the peace of mind was priceless.

Case Study 2: Safety for a Commercial Workshop

A furniture maker in his final years of practice brought me in on his commercial shop to address electrical safety on the job site once insurance requirements had shifted. We fitted Type F RCDs for his CNC machines and dedusters. Its enhanced detection has already stopped three potential fires in the first month — DC faults that his old Type AC units wou