Busbar Protection That Stays Ahead Of Every Fault.
MiCOM P74x delivers fast, secure, and scalable numerical biased protection for every substation layout — single, double, ring, or breaker-and-a-half.
A Busbar Fault Hits Hard.
Slow Protection Hits Harder.
Legacy schemes falter with CT saturation and missed isolator states. The result? Mis-trips, blind spots, and long outages across critical grid nodes.
Slow trip logic
Legacy schemes fail to clear high-current bus faults within grid stability windows.
Weak CT supervision
Inability to handle saturation or open circuits leads to catastrophic false trips.
Unstable zone control
Manual logic struggles to track isolator states in double-bus or mesh schemes.
Poor fault discrimination
Generic relays lack sensitivity to distinguish between internal and through-faults.
Meet MiCOM P74x
— Numerical busbar protection for modern substations.
P741, P742 and P743 bring numerical biased differential protection built for multi-bus, multi-feeder environments. Central and peripheral units work over high-speed optical links to block saturation and validate trips via dedicated check zones.
Fast. Firm.
Fault-Smart.
Purpose-built algorithms that keep busbars stable under any topology condition.
Check-zone assurance
Two-level numerical validation avoids unwanted trips even in complex topologies.
Breaker & isolator intelligence
Live state monitoring ensures switching operations reflect the true bus topology.
Built-in backup
Overcurrent, earth-fault and breaker-failure add layered security to every section.
Deep disturbance records
High-res waveforms, SOE and diagnostics for rapid forensic post-fault analysis.
Scalable architecture
Central (CU) and peripheral (PU) units adapt to any bus arrangement or size.
High-speed differential
Phase-segregated logic, stable during heavy CT saturation and grid surges.
Designed For Secure High-Current Environments
Powerful logic with flexible scalable architecture
Built For Every Busbar Philosophy
Simple or complex, P74x fits the arrangement with absolute security.
Transfer Bus
Dynamic topology tracking for substations with main and transfer buses.
Breaker-and-a-half
High-availability differential logic for critical EHV/HV grid nodes.
Ring Bus arrangements
Selective zone protection for loop-connected substation designs.
Multi-feeder substations
Scalable architecture handling up to 28 feeders per central unit.
Single bus systems
Compact P741 deployment for straightforward industrial switchyards.
Bus Coupler logic
Specialised logic for secure coupler and bus section operations.
Transfer Bus
Dynamic topology tracking for substations with main and transfer buses.
Breaker-and-a-half
High-availability differential logic for critical EHV/HV grid nodes.
Ring Bus arrangements
Selective zone protection for loop-connected substation designs.
Multi-feeder substations
Scalable architecture handling up to 28 feeders per central unit.
Single bus systems
Compact P741 deployment for straightforward industrial switchyards.
Bus Coupler logic
Specialised logic for secure coupler and bus section operations.
Busbar Protection Configured
Right
We map your zones, CTs and isolators for precise settings.
Relay Testing, Programming &
Configuration
Technical Implementation
- Isolator auxiliary state mapping
- Check-zone logic calibration
- Sub-cycle stability verification
Confidence Where
The Grid Converges
Critical nodes demand protection that never hesitates
Transmission utilities
HV/MV substations
Industrial switchyards
Generation switchyards
Renewable integration hubs
Coordinated Substation Suite.
Compatible protection, monitoring, and communication products for complete schemes.
MiCOM Px40 Series
MiCOM P14x
MiCOM Px40 Series
MiCOM P24x
MiCOM Px40 Series
MiCOM P34x
MiCOM Px40 Series
MiCOM P44x
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MiCOM P54x
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MiCOM P64x
MiCOM Px40 Series
MiCOM P740
MiCOM Px40 Series
MiCOM P841
MiCOM Px40 Series