National Light Sources | 20Amp 6kA 4 Pole RCBO | Type A
The NLS 30821 is a 20 amp 6kA 4 Pole RCBO (Residual Current Breaker with Overcurrent) combining circuit protection with earth leakage detection, meeting AS/NZ 61009-1 standard for electrical safety and shock risk minimisation in switchboard installations.
Three-phase domestic and light commercial switchboards benefit from a dedicated RCBO per phase circuit. The 30mA Type A sensitivity detects sinusoidal alternating residual currents, covering standard fault conditions on most circuits. The 20A rating suits general-purpose three-phase loads and sub-board protection where high breaking capacity (6kA) handles fault clearance reliably. Licensed sparkies value the NLS 30821 for retrofit upgrades to older switchboards and new installations where compact DIN rail mounting and pre-termination to 25mm² cable reduce on-site installation time.
The NLS range delivers solid performance at a competitive price point, making it a cost-effective alternative to premium brands while maintaining compliance and reliability. Installers stock the 30821 for repeatability across multi-unit residential work and light commercial installations, knowing it will operate trouble-free without maintenance calls.
Features
- Type A sensitivity — 30mA detection of sinusoidal alternating residual currents, the industry-standard type for most domestic and commercial circuits.
- 4 Pole 3P+N configuration — protects three phases and neutral with a single compact device, reducing switchboard complexity and wiring.
- 20 Amp rated current — suitable for general-purpose three-phase circuits and sub-board distribution where total load per phase does not exceed 20A.
- 6kA breaking capacity — handles fault currents reliably up to 6000 amps, meeting safety requirements for most domestic and light commercial installations.
- DIN rail mounting — snap-fits to standard 35mm DIN rail, compatible with all common Australian switchboard configurations.
- Lockable toggle — manual on-off switch with a mechanical lock mechanism, preventing accidental trip during high-vibration or dynamic load conditions.
- Terminals suitable for up to 25mm² cable — larger cable capacity reduces the need for downsizing or double-terminating on high-load circuits.
- IP20 rated (IP40 when enclosed) — suitable for indoor switchboard use; IP40 when installed in a cabinet or enclosure for extra protection against dust and splash.
- Curve C characteristic — responds appropriately to transient inrush currents (motors, transformers) without nuisance tripping on normal load surges.
- Compact size — 84mm height, 71mm width, 80mm depth occupies minimal switchboard space, leaving room for additional protection devices.
Where to use
- Three-phase domestic installation upgrades — the NLS 30821 provides individual circuit protection on retrofit switchboard upgrades where older boards lack per-circuit RCBOs.
- Light commercial sub-boards — small office, retail, and workshop distributions benefit from the 20A 3P+N configuration on circuits serving lighting, power, or heating loads.
- Multi-unit residential installations — apartment blocks and townhouse developments where each dwelling's sub-board requires a dedicated 20A RCBO for the main or submain distribution.
- Industrial control circuits — manufacturing facilities and workshop equipment circuits where individual machine protection and residual current detection are required.
- Renovation and new build switchboards — standard specification for electricians modernising older boards or wiring new residential and commercial premises to current Australian Standards.
- Backup and standby power circuits — sub-board protection on generator or UPS switchboards where parallel supply arrangements require individual phase protection.
The NLS 30821 is not suitable for single-phase circuits (it is a three-phase device requiring all three phase conductors to operate correctly). Do not install the 30821 on single-phase domestic installations or where only two phases are present. It is rated for indoor DIN rail installation only and must not be exposed to wet, corrosive, or outdoor environments exceeding IP20 (IP40 when enclosed). Installation and commissioning must be carried out by a licensed electrician in accordance with AS/NZS 3000.
Verified Sparky Direct customer reviews: NLS 30821 | 20Amp 6kA | 4 Pole RCBO | Type A (30821)
"Good price point." — Matt
"Have been using these for a couple of years now. No problems yet." — Cl
"Easy to install." — Benji
