CBi-electric: low voltage looks at why earth leakage protection is the most critical call you'll make on site.
Earth leakage protection devices (ELPDs) are mandatory in South Africa for a reason. When something goes wrong on site, it’s the installer who’s held accountable, not the manufacturer, supplier, or wholesaler. Lives, liability, and professional reputations all hang on a single point of failure: the device you choose to install.
“Get it wrong, and you’re risking far more than a technical fault,” says Dr Andrew Dickson, engineering executive at CBi-electric: low voltage. “You’re putting human lives and your career on the line.”
What happens when current takes an unintended path
ELPDs monitor current flow in a circuit and trip when they detect even a slight imbalance – the signal that current is leaking to ground instead of returning via the neutral conductor. Sometimes, this is through a person’s body. “It doesn’t take a large current to do serious harm,” warns Dr Dickson. “Currents over 30 milliamps (mA) can be fatal. That’s why our devices are designed to trip between 23 and 27 mA. A few milliamps, and a few milliseconds, can make the difference between life and death.”
Here’s how the human body responds to electrical current:
- 1 mA: Tingling, but easy to ignore
- 5 mA: Unpleasant shock
- 10–20 mA: Muscle control lost, limit of being able to let go
- 30+ mA: Breathing disrupted; heart rhythm affected
- 50+ mA: Burns, unconsciousness, or death
This is why the safety threshold is 30 mA, and why devices must be accurate and reliable in tripping below that point.
Compliance isn’t a suggestion, it’s the law
South African law requires that all earth leakage devices meet the National Regulator for Compulsory Specifications’ (NRCS) VC 8035 specification, which sets safety and performance standards. “If you install a device that doesn’t comply, you carry the legal liability,” cautions Dr Dickson.
To ensure compliance and reliability, he recommends:
- Confirming SABS or equivalent certification;
- Checking that the trip level is 30 mA or less; and
- Avoiding unbranded or generic products that may fail testing.
Nuisance tripping shouldn’t be ignored
Unexpected trips are often brushed off as a nuisance, but Dr Dickson points out that they could signal bigger issues. “You might be dealing with high cumulative leakage, poor wiring, contaminated terminals, overloaded circuits, or equipment generating unwanted current loss.”
He stresses that proper fault-finding, including measuring leakage levels and tracking variation across appliances, is essential. “Ignoring these symptoms could mean missing the early warning signs of system failure or injury risk.”
The buck stops with the installer
“You can’t outsource responsibility,” notes Dr Dickson. “You need to know exactly what you’re installing and ensure it meets the legal and technical standards. Certification, compliance, and correct specifications are non-negotiable.”
CBi-electric: low voltage manufactures high-quality, NRCS-compliant ELPDs that are tested for local conditions, whether for homes, commercial buildings, or industrial applications. “We build products to protect people and your professional integrity,” he concludes.
