Automated grid isolation for medium voltage embedded generation. Detects under-voltage, over-voltage, and phase loss — then physically disconnects your installation within milliseconds.
When the grid goes down, embedded generation can backfeed live voltage into the MV network, endangering lives and equipment.
Need to get compliant? We install in 2-3 days with no primary equipment modification.
A fully automated protection device that detects grid anomalies and physically disconnects the consumer from the MV network.
Three capacitive voltage sensors feed per-phase voltage data via dual CT secondary inputs.
When voltage falls below the 4-stage IDMT threshold or exceeds 112.7%, the controller triggers.
24 VDC battery-backed trip ensures physical disconnection even during total grid loss.
After 4 minutes of stable 90-112.7% voltage on all phases, automatic reconnection.
Microcontroller with configurable UV/OV thresholds, LED matrix, AUTO/MANUAL key-switch.
3 × capacitive sensors (11 kV or 22 kV). Class 0.5 accuracy.
Spring-charge mechanism for motorised CB or isolator drive.
24 VDC backup ensures trip during complete grid loss.
Motorised switchgear interface matched to your equipment.
Threshold |
kV |
Delay |
|---|---|---|
< 30%
|
< 6.6 kV
|
Instant
|
< 60%
|
< 13.2 kV
|
100 ms
|
< 80%
|
< 17.6 kV
|
300 ms
|
< 90%
|
< 19.8 kV
|
800 ms
|
Enclosure
|
Takachi aluminium, IP54
|
Input Voltage
|
11 kV or 22 kV via VTs
|
Operating Mode
|
AUTO / MANUAL (key-switch)
|
Accuracy Class
|
Class 0.5
|
Panel Dimensions
|
180 × 195 mm
|
Auxiliary Supply
|
24 VDC (battery-backed)
|
Indication
|
LED matrix per-phase
|
Standards
|
NRS 097-2-3, SANS 10142-1
|
Retrofit installation — no primary equipment modification required
Integrated with diesel generators and solar SSEG. Full auto mode since 2025.
Heavy industrial loads with large embedded generation. Rapid disconnection via motorised isolator.
Critical telecoms infrastructure with multiple backup power sources.
Grid-connected embedded generation islanding protection requirements.
Wiring of premises. Compliance of the controller wiring and installation.
Physical isolation required at the point of connection.
Important: The EZY Islanding Controller provides the protection functions required by NRS 097-2-3. Full compliance also requires correct wiring per SANS 10142-1, proper earthing, and commissioning by a qualified person.
The controller continuously monitors all three phases of your MV supply. When it detects under-voltage (4-stage IDMT from instantaneous at <30% to 800ms at <90%), over-voltage (>112.7% with 5-second delay), or loss of any single phase, it sends a trip command to physically disconnect your installation from the grid via a motorised circuit breaker or isolator. A 24 VDC battery backup ensures this trip executes even during complete grid loss. Once the grid recovers and all three phases are stable within 90-112.7% of nominal for 4 consecutive minutes, it automatically reconnects.
When a grid fault clears, voltage does not snap back to normal instantly. There is a recovery transient with oscillations, dips, and surges that can last several minutes. If you reconnect during this transient, you risk out-of-phase reconnection which causes severe voltage spikes and insulation damage. The 4-minute timer resets to zero every time voltage dips below threshold, ensuring the grid is genuinely stable before reconnection occurs.
The system retrofits into Schneider RM6, ABB SafeRing/SafePlus, Siemens 8DJH, and TGood RMU switchgear. No modification to the primary switchgear is required. The controller interfaces with the motorised mechanism of the circuit breaker or isolator. Available in both 11 kV and 22 kV variants.
The controller provides the protection functions specified in NRS 097-2-3: under-voltage, over-voltage, phase loss detection, physical disconnection, and timed reconnection. However, full compliance also depends on correct installation wiring (per SANS 10142-1), proper earthing, and commissioning by a qualified person.
Typical installation in existing switchgear takes 2-3 days. This includes mounting the controller, installing the voltage sensors, fitting the motor mechanism and battery tripping unit, wiring, and commissioning. No primary switchgear modification is required.
The 24 VDC battery tripping unit provides backup power specifically for this scenario. Even with no AC supply available, the battery ensures the trip command is executed and the isolator operates.
If your solar installation or generator is connected at medium voltage (11 kV or 22 kV) and feeds into the municipal grid, then yes. NRS 097-2-3 and most municipal bylaws require anti-islanding protection at the point of common coupling for all embedded generation.
Speak to our specialists today. We install in 2-3 days with no primary equipment modification.
Talk to specialists who focus on solving the problem - not just selling equipment.
© 2026 Created by EZY Switchgear
