Why Choose the ABB ELR48V24P Residual Current Monitor?
The ABB ELR48V24P is a compact electronic Type A residual current monitor and relay designed for monitoring and protection of low-voltage electrical distribution networks. As part of ABB’s Earth Monitoring Devices range, it operates with an external toroidal transformer to detect residual current and control associated circuit protection equipment when the configured threshold is exceeded.
Designed for 48 × 48 mm front-panel mounting, the ELR48V24P combines adjustable residual current sensitivity and trip delay with selectable Fail Safe and automatic reset functions. Front-mounted TEST and RESET controls, together with ON and FAULT LED indication, provide straightforward commissioning and operational status monitoring.
The ELR48V24P operates from a 24–48 V AC/DC auxiliary supply and provides adjustable residual current sensitivity from 0.03–30 A with a configurable delay from 0–5 s. Its compact construction makes it particularly suitable for industrial control panels, machinery and switchboards where panel space is limited but configurable earth leakage monitoring is required.
Key Advantages
- Compact 48 × 48 mm Type A residual current monitor for space-conscious panel installations.
- 24–48 V AC/DC auxiliary supply suitable for low-voltage industrial control systems.
- 0.03–30 A adjustable residual current sensitivity supports a wide range of monitoring requirements.
- 0–5 s adjustable trip delay enables protection coordination and selectivity.
- Selectable Fail Safe and automatic reset functions provide flexible system configuration.
- Designed for use with compatible ABB TR-series toroidal transformers.
Key Features
- ABB ELR residual current relay series.
- Type A residual current detection.
- 24–48 V AC/DC auxiliary supply.
- 0.03–30 A adjustable residual current sensitivity.
- 0–5 s adjustable operating delay.
- Fail Safe function selectable by configuration.
- Automatic or manual reset selectable by configuration.
- Front-mounted TEST and RESET pushbuttons.
- ON and FAULT LED status indication.
- 5 A at 250 V output contact capacity.
- Compatible with ABB TR-series external toroidal transformers.
- Complies with IEC/EN 60947-2 Annex M.
Compact and Adjustable Earth Leakage Monitoring
The ABB ELR48V24P operates with an external toroidal transformer through which the active conductors of the protected circuit are routed. Under normal operating conditions, the vector sum of the currents through the toroid is effectively zero. An insulation fault or leakage to earth creates a residual current imbalance, which is detected by the toroidal transformer and transmitted to the ELR48V24P.
The monitor compares this residual current with the selected sensitivity setting and operates its output contact when the configured threshold and time delay conditions are reached. With sensitivity adjustable between 0.03 and 30 A, delay adjustable up to 5 s and selectable Fail Safe and automatic reset functions, the ELR48V24P provides flexible residual current monitoring for commercial and industrial low-voltage systems.
Typical Applications
- Industrial low-voltage distribution systems.
- Compact electrical switchboards and distribution panels.
- Industrial control panels using 24–48 V auxiliary supplies.
- Machinery and automation systems.
- Earth leakage monitoring with ABB TR-series toroidal transformers.
- Protection systems incorporating suitable MCBs or MCCBs and tripping accessories.
