Why Choose the ABB ELR72V24 Residual Current Monitor?
The ABB ELR72V24 is a front-panel electronic residual current monitor designed for earth leakage monitoring and protection in low-voltage electrical distribution systems. As part of the ABB ELR residual current relay series, it operates in conjunction with a separate external ABB TR series toroidal transformer to continuously detect residual current and initiate circuit-breaker tripping when the configured threshold is exceeded.
Designed in a compact 72 × 72 mm front-panel format, the ELR72V24 provides adjustable residual current sensitivity and operating delay for flexible protection coordination. Its Type A residual current detection makes it suitable for monitoring alternating and pulsating DC residual currents, while adjustable Fail Safe and autoreset functions support dependable operation in industrial and commercial electrical installations.
The ELR72V24 operates from a 24–48 V AC/DC auxiliary supply at 50–60 Hz. Sensitivity can be configured across a broad 0.03–30 A range and the operating delay can be adjusted from 0–5 s, allowing the monitor to be coordinated with the protection requirements of the installation.
Key Advantages
- Electronic residual current monitoring and protection for low-voltage distribution systems.
- 24–48 V AC/DC auxiliary supply for integration into industrial control systems.
- Wide 0.03–30 A adjustable sensitivity range.
- Adjustable 0–5 s tripping delay supports selective protection coordination.
- Type A residual current detection for AC and pulsating DC residual currents.
- Works with separate ABB TR series toroidal transformers.
- Adjustable Fail Safe and autoreset functions.
- Front-panel mounting provides convenient access to settings, test and reset controls.
Key Features
- ABB ELR series residual current monitor.
- 72 × 72 mm front-panel format.
- 24–48 V AC/DC operating voltage.
- 50–60 Hz rated frequency.
- 0.03–30 A adjustable residual current sensitivity.
- 0–5 s adjustable delay time.
- 5 A at 250 V output contact capacity.
- Front-mounted TEST and RESET pushbuttons.
- LED indication for auxiliary supply and fault/trip status.
- Compliant with IEC/EN 60947-2 Annex M.
Reliable Residual Current Protection for Electrical Distribution
The ABB ELR72V24 operates with an external toroidal transformer installed around the active conductors of the monitored circuit. The toroid continuously detects the vector sum of the conductor currents; when leakage to earth produces an imbalance above the selected threshold, the ELR72V24 changes the state of its output contacts so that the associated protection system can disconnect the circuit.
Its adjustable 0.03–30 A sensitivity and 0–5 s operating delay allow the protection characteristics to be adapted to different installations and coordinated with upstream and downstream protective devices. Combined with suitable circuit breakers, shunt trips and ABB toroidal transformers, the ELR72V24 provides a flexible solution for residual current supervision in industrial and commercial distribution networks.
Typical Applications
- Industrial low-voltage distribution systems.
- Electrical switchboards and control panels.
- Earth leakage and residual current monitoring.
- Industrial machinery and production equipment.
- Commercial building electrical distribution.
- Protection systems using circuit breakers and shunt-trip releases.
