Ensure safe DC-grid selectivity

VACON® NXP DCGuard™ enables fast disconnection and full selectivity be­tween DC grids for all VACON® NXP series drives.

Utilizing DC grids rather than AC grids enables power distribution with lower power losses. However, ensuring selectivity and limited short circuit energy requires more sophisticated protection devices.

VACON® NXP DCGuard™ is a semiconduc­tor protection device that maintains the stability of the DC grid by detecting and cutting off any faulty DC currents, fast. It isolates the faulty part of the system within 5 microseconds, protecting the surrounding equipment and ensuring uninterrupted operation.

VACON® NXP DCGuard has DNV-GL, ABS, and Lloyd's Register type approvals, simplifying system approval for use in marine environments.

Current range

465-800 VDC………3-4140 A

640-1100 VDC…..….4-3100 A

Features and benefits

  • Correct system selectivity due to short circuit protection
  • No overvoltage spikes at current cut-off
  • Connect two different DC grids with voltage differences up to full DC voltage, thanks to controlled voltage ramp-up
  • Transmission cable overload protection
  • Reliable, proven technology
DC grids and selectivity using VACON® NXP DCGuard™

DC grids and selectivity using VACON® NXP DCGuard™

Utilizing DC grids instead of AC grids can improve system efficiency and system footprint by up to 20%. And there is a significant potential for energy saving especially when combining DC grids, energy storage and/or variable speed generators.


Type Name Language Valid for Updated Download File type
Application guide - AB VACON NXP DCGuard Application Guide English Multiple 05 Dec, 2018 1.8 MB PDF
Design guide - AJ VACON NXP DCGuard Design Guide English Multiple 05 Dec, 2018 3.5 MB PDF
Operating guide - AQ VACON NXP DCGuard Operating Guide English Multiple 13 Nov, 2018 2.4 MB PDF
Fact sheet - AM VACON® NXP DCGuard™ English Multiple 05 Mar, 2019 517.3 KB PDF


Type Name Language Updated Version Status Download File type
Fieldbus Configuration Files VACON® OPTEA SIMATIC PDM EDD 13 Nov, 2018 RL 461.7 KB ZIP

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Case studies

  • VACON® drives power hybrid ferries 24/7
    VACON® drives power hybrid ferries 24/7

    Passenger ferries bridge Amsterdam’s IJ River, keeping the city connected around the clock. Hybrid propulsion powered by VACON® drives ensures 24/7 uptime, smaller generator size, better air quality, less noise and easy maneuverability of the vessels.