RCCBs in Malaysia: sensitivity, Type A versus Type AC, and what to order

An RCCB — residual current circuit breaker — is the device that watches for current leaking to earth. It compares the current flowing out on the live conductor with the current coming back on the neutral. When the two differ by more than its sensitivity setting, some current is finding another path — through a faulty appliance, a damaged cable, or a person — and the RCCB disconnects.

That’s a different job from an MCB, which only protects wiring against overload and short circuit. An RCCB has no thermal-magnetic overcurrent protection of its own, so it needs coordinated overcurrent protection elsewhere in the circuit — an upstream or paired MCB — to clear an overload or short circuit. A single device that does both is an RCBO: overcurrent and residual protection combined in one unit. If your board has separate MCBs with one RCCB on the incoming side, you have the split arrangement; an RCBO puts both functions in a single device. An RCCB doesn’t protect against voltage surges either; that’s a surge protective device, which the Energy Commission’s example layouts place after the main switch and ahead of the RCCBs.

Four specifications, not one

Something like “2P 40A 30mA Type A” is four independent properties, and getting any one wrong gives you the wrong device.

Poles. Two-pole (2P) devices suit single-phase supplies; four-pole (4P) units handle three-phase. On the common modular frames a 2P unit takes two modules and a 4P unit four — but module width isn’t universal, so check the actual datasheet for the device you’re fitting. Hager Malaysia’s CD240J, for instance, is a 2-pole, 2-module device measuring 35mm wide.

Rated current. The 40A or 63A figure is how much load current the device is designed to carry continuously. It is not the leakage at which it trips.

Residual sensitivity. Written in milliamperes — 10mA, 30mA, 100mA, 300mA. This is the imbalance between live and neutral that trips the device. A lower number means it reacts to less leakage, so 10mA is more sensitive than 30mA, and 100mA and 300mA are less sensitive still. Different sensitivities suit different circuits, which is why Malaysian rules specify more than one value (more on that below).

Residual type. This is the letter that trips people up. It describes which shapes of fault current the device is specified to detect, defined in IEC 60755. Type AC detects sinusoidal alternating residual current only. Type A also detects pulsating DC residual current, the kind produced by diode or thyristor rectifier circuits in single-phase electronic loads. Type F adds detection for composite multi-frequency residual current and is aimed at single-phase variable-speed drives. Type B extends to smooth DC residual current as well, for three-phase rectifier loads such as variable-speed drives, PV inverters and EV charging equipment.

Two caveats stop this being a simple ladder. Each type is specified against particular test waveforms, so whether a device is appropriate comes from the equipment it’s protecting and the device’s own specification — a Type A device is not automatically right just because it’s “higher” than Type AC. And the letter here has nothing to do with an MCB’s B, C, D curve, which describes magnetic trip thresholds. Same alphabet, unrelated meaning.

Maxguard’s RCCB range in detail

Maxguard’s ML63-1 and ML100-1 series is a Malaysian-brand option, and the catalogue is helpfully specific about which variant is which — which matters, because Maxguard sells both Type AC and Type A under the same family name. The model code is what distinguishes them, not the series.

Type AC devices carry an N suffix; Type A carries an A. A 40A two-pole 30mA Type AC unit is E40203N, and the equivalent Type A is E40203A. A 63A two-pole 30mA Type A is E63203A. The four-pole codes put a 4 in the pole position: E40403A for 40A 4P 30mA Type A, and E63410A for 63A 4P 100mA Type A.

Sensitivities span 10, 30, 100 and 300mA. The 10mA option appears once, as E25201N — a 25A 2P Type AC device. The 300mA versions are Type AC only in the catalogue, and the 100A ML100-1 family tops out in four-pole Type AC: E100403N (30mA), E100410N (100mA) and E100430N (300mA). If you need Type A, the catalogue’s range is narrower than the family page suggests, so match the exact code.

These are IEC 61008-2-1 devices, rated 230/400V and 240/415V at 50/60Hz, IP20, pollution degree 3, with over 2,000 operating cycles. Maxguard also quotes a conditional surge current proof of 3,000A at 8/20µs.

One number to read carefully: the catalogue lists a “rated conditional short-circuit breaking capacity (Icn) of 10kA, with 10kA back-up fuse”. That conditional rating is stated with the manufacturer’s own specified backup protection upstream — so it is a rating that depends on a suitable fuse being there, not a stand-alone short-circuit rating the way an MCB’s Icn is. Don’t order an RCCB expecting it to clear a fault on its own.

Schneider’s residual ranges and the Hager comparison

Schneider’s Acti9 iID is its modular residual-current range, and the four Type A 30mA models Malaysian retailer Exerlon groups together show how the codes work:

• A9R51240 — 2P, 40A, 30mA, Type A
• A9R51263 — 2P, 63A, 30mA, Type A
• A9R51440 — 4P, 40A, 30mA, Type A
• A9R51463 — 4P, 63A, 30mA, Type A

Those four are the 30mA Type A models one retailer lists side by side — not the whole Acti9 iID family, which spans wider ratings and other residual types; the Acti9 iID page covers all 110 references on Schneider Malaysia’s list. On that retailer’s online item prices, the four run from RM250 for the 2P/40A up to RM420 for the 4P/63A, and the step from two poles to four costs more than the step from 40A to 63A within the same pole count. Those are item prices, not delivered quotes, and they change — use them as a rough reference and confirm the current offer.

Schneider’s Easy9 line is the residential and small-business range. Its RCCBs are Type AC apart from one 10mA Type A model, and the exact variant you get depends on the order code. The Easy9 and Acti9 overviews compare the two series.

Hager’s CD240J is a comparable 2-pole, 40A, 30mA Type A device on Hager Malaysia’s catalogue, 35mm wide with a 6kA rated conditional short-circuit current to EN 61008-1 and a 1.5kA making and breaking capacity. Hager Malaysia lists 63 RCCBs, including four 10mA models; its product page gives ratings, not Malaysian stock or pricing. The Hager RCCB page covers those 10mA models and Malaysian prices, and the Hager brand page the rest of what we’ve researched.

Himel and ABB, and the 10mA price spread

Two more brands that Malaysian electricians name often sit at opposite ends of the price range. Neither has a Malaysian product list online, so our pages build their tables from Malaysian distributor and price-list sources.

Himel, a budget brand priced around Maxguard, sells two RCCB series, HDB6VR and HDB3VR, in 2 and 4 poles from 25A to 100A. The code spells the rating out: HDB6VR225LC is 2-pole, 25A, 10mA (L), Type AC (C). Each series has one 10mA rating, 2P 25A Type AC, and the HDB3VR adds three Type A codes at 30mA: HDB3VR240SA, HDB3VR263SA and HDB3VR440SA. We found no Malaysian datasheet for either series, so their standard part and short-circuit rating aren’t known here.

ABB, in the premium tier, sells the F202 and F204 (and FH202/FH204). ABB’s designation also spells the rating out: F202 AC-25/0.01 is 2-pole, Type AC, 25A, 0.01A (10mA). The 10mA options in KVC’s catalogue are all 2-pole: F202 AC-16/0.01, F202 AC-25/0.01 and the Type A F202 A-16/0.01. JKR’s approved list records ABB’s RCCBs as made in Italy, and Himel’s as made in China.

At the water-heater rating, 2-pole 25A 10mA Type AC, the spread across researched brands is wide. These are October 2026 shop or marketplace prices, not like-for-like datasheet comparisons:

Buy by the full code

The habit that saves the most trouble is ordering by full model code. “40 amp RCCB” could be 2-pole or 4-pole, 30mA or 100mA, Type AC or Type A — eight different products. E40203A, A9R51240, CD240J, HDB3VR240SA and F202 A-63/0.03 each name exactly one device.

On the supply side, Maxguard’s codes and sensitivities are published on its ML63-1/ML100-1 product page and in its catalogue, and its devices reach buyers through electrical wholesalers. Schneider’s Acti9 and Easy9 residual devices come through its distributor network, which in Johor Bahru includes Maydenki, Synoview Electric and Genuine Electric. Whether a branch stocks a specific code is a separate question from whether the brand is sold locally, so it’s worth confirming before a trip.

Equipment that changes the type

Type A handles the single-phase electronic loads common in a modern house, but it isn’t automatically the answer for everything.

Single-phase variable-speed drives — increasingly common in washing machines and air-conditioners — can produce residual current waveforms that call for Type F. Three-phase rectifier loads, including larger variable-speed drives, PV inverters and EV charging equipment, can produce smooth DC residual current that only Type B detects. Whether a particular EV charger or inverter needs Type B comes from that equipment and the installation design — not from a general rule that “Type A is for EV chargers”. If a manufacturer specifies Type B for their equipment, a Type A device does not satisfy it.

What Malaysian rules expect

Malaysia’s domestic wiring requirements are set out in the Suruhanjaya Tenaga Garis Panduan Pendawaian Elektrik Pepasangan Domestik. The guide requires residual-current protection on final circuits using a current-operated device (the older voltage-operated ELCB is not permitted), and its sensitivity requirements are more specific than the single 30mA figure many people assume.

Under Rule 36 of the Electricity Regulations 1994, as set out in the guide:

• 10mA or less for public entertainment premises and for floors likely to be wet or low-resistance walls and enclosures — the guide’s examples include pools, garden and fence lighting, and water-heater circuits.
• 30mA or less for equipment, apparatus or tools held in the hand — for example socket outlet circuits.
• 100mA or less for other installations — for example lighting, fan and air-conditioning circuits.

The guide also classifies residual devices by their DC response (types AC, A, B and F), notes Type AC as the most common in Malaysian home wiring, encourages Type A where many electronic devices are used, and encourages Types B and F where inverter-equipped equipment is installed. That guidance lines up with the type discussion above: Type AC covers the traditional case, Type A adds detection for the pulsating DC from single-phase electronics, and Types B and F extend it to the composite and smooth DC waveforms that inverter-driven loads can produce. It requires the RCCB’s rated conditional short-circuit current to be at least the upstream breaker’s breaking capacity.

Selection itself depends on the supply arrangement, the earthing system, how devices discriminate with upstream and downstream protection, and the loads involved — the things an installer has to work out for a specific board. Use the labels above to identify the right product and the right code, then let a competent person confirm the design.