Why Your Generator Set Needs an ELR: A Guide to Safe Generator Operation in Australia

Generator sets are essential on Australian worksites—from the Pilbara mines to Queensland farms—but even a hidden electrical fault can turn a critical power source into a serious hazard. Installing an Earth Leakage Relay (ELR) is not just a smart choice; it is a legal requirement under Australian safety standards.

What is an ELR and Why It Matters

Earth faults can cause deadly electric shocks or fires. Traditional circuit breakers only respond to large short-circuits and cannot detect small leakage currents. An ELR or Residual Current Device (RCD) detects imbalances in current flowing in and out of a circuit—currents leaking to the ground.

ELRs are designed to detect even tiny leakage currents (as low as 30 mA), providing protection for both personnel and equipment. Without an ELR, aging cables, damp environments, or insulation degradation may go unnoticed, creating hidden risks.

According to NHP, one of Australia’s largest industrial switchgear suppliers, exposure to just 30 mA of leakage current can cause ventricular fibrillation or death, a level that standard breakers cannot detect.

Why Generators Are High-Risk for Leakage

Unlike mains electricity, generators are independent power sources. The grounding method (TT system) often used in portable or older generators has high earth resistance, creating small fault currents that traditional breakers may not detect.

Generators frequently operate in harsh, humid, dusty, and vibrating environments, accelerating insulation aging. Continuous ELR monitoring is therefore critical for safe operation.

Key Benefits of ELR for Generator Safety

1.  Protects People: In high-risk areas like mines, leakage currents above 30 mA can be fatal. ELRs detect and cut off dangerous currents in milliseconds—something standard breakers cannot do.

2.  Prevents Fires: Leakage currents can energize enclosures, steel structures, or nearby combustible materials. On farms or mines, even a tiny spark can ignite fire or combustible gas.

3.  Extends Equipment Life: Persistent leakage accelerates insulation wear, leading to premature failure and unexpected capital expenses.

4.  Ensures Compliance: ELR protection is required under AS/NZS 2081.3 and general workplace safety laws (WHS). Lack of proper ELR can lead to fines, insurance issues, and project downtime.

ELR is not optional—it’s a critical link between safe power and continuous operations.

When and Where to Use ELR in Australia

Not all leakage protection devices are suitable for personnel safety. According to AS 3190, only certified RCDs with rated sensitivity of 10–30 mA can be used for human protection.

● Residential or office outlets: RCDs (10–30 mA)

● Industrial equipment: Ground leakage relays (ELR) 30 mA–30 A

● Mining & high-risk industries: Specialized ELRs (e.g., TERASAKI DSRM72 series, 30–500 mA)

Key Compliance Standards: AS 3190, AS/NZS 61008, AS/NZS 61009, AS/NZS 2081.3:2002

How to Select the Right ELR: Four-Step Checklist

Selection Tips:

1.  Define purpose: Choose between personnel protection (RCD, 10–30 mA) and equipment protection (industrial ELR, adjustable 30 mA–30 A).

2.  Check certifications: Ensure RCM mark, AS/NZS compliance, or IEC 60947-2 certification.

3.  Verify parameters: Sensitivity, trip time, optional features like delay, remote alarm, and self-locking for mining applications.

Conclusion

In Australia, generator safety is non-negotiable. Installing a compliant ELR is no longer optional—it protects human life, equipment, and continuous operation, while ensuring regulatory compliance.

Voltgent provides expert guidance on ELR selection and supplies certified, compliant products for Australian generators. Protect your power, protect your people, and maintain uninterrupted operations with the right ELR. Contact Voltgent for more infomation about your genset inqury!