DC / Battery Converter Protection Relay (SYMAP®)

DC systems and batteries, dedicated protection and monitoring

Battery energy storage installations (BESS) and hybrid vessel power architectures need a different protection device family than AC systems. Direct DC current and voltage measurement, shunt and transducer inputs, polarity-aware fault logic and the use of available signals from the battery management system (BMS) define the application.

SYMAP^® is not a BMS replacement. SYMAP^® Y-BAT and Y-DC variants provide DC-side protection (overcurrent, earth-fault, undervoltage, breaker control) and use available signals from the BMS over Modbus or IEC 61850, where provided by the project.

Typical DC applications

BESS, battery storage

Grid-connected battery storage installations. DC monitoring on the battery side (Y-BAT), AC grid connection through Compact+ GC with NA protection and Grid Code logic.

Hybrid vessels

Diesel, battery and converter architectures with battery storage in the power management system; peak shaving and spinning-reserve reduction. Uses available battery signals, not a BMS replacement. Hybrid marine applications use the SYMAP^® product family, certified by major marine classification societies (DNV, Bureau Veritas, Lloyd's Register), where applicable to the selected device and configuration.

Compact+ or classic SYMAP^®?

Classic SYMAP^® Y-DC / Y-BAT is the dedicated variant for DC and battery applications with DC measurement, shunt/transducer inputs and the use of available BMS and SCADA signals. SYMAP^® Compact+ GC applies to the AC grid connection of BESS installations (NA protection, Grid Code). SYMAP^® is not a BMS replacement, it uses available signals from the BMS where provided by the project.

Products covering DC applications

Need detailed technical specifications?

For exact protection function coverage, settings ranges, DC measurement specifications, shunt/transducer interface, battery signal integration and configuration support, contact our team to receive the relevant datasheet and engineering proposal.

Request datasheet Engineering inquiry

DC system and battery protection