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residual current circuit-breaker DFS 4 025-4/0,50-B SK
Residual current circuit-breakers, four-pole, 25 A, 0,5 A, Type B SK, N left

Function:
Type B residual current circuit-breakers are AC-DC sensitive. The SK characteristic limits the risk of unwanted tripping providing maximum system availability, for frequencies ranging from 0 to 150 kHz. With low tripping sensitivity at higher frequencies, our SK circuit-breakers are perfectly suited for use in facilities where preventive fire protection measures are provided by additional means. Standard RCCBs are designed for circuits with 230/400 V at 50 Hz.

Features:
High level of immunity against leakage and residual currents due to operational conditions from frequency 1 kHz and higher, AC/DC sensitive for residual currents with frequencies and mixed frequencies of 0 Hz (smooth direct current) up to 150 kHz, high availability even of voltage-independent detection of smooth DC residual current and AC residual current with frequencies not equal to 50/60 Hz thanks to full functional compatibility with mains voltages from at least 50 V AC on any two active conductors, mains-voltage-independent tripping when type A residual currents occur , compact design for all rated currents, high short-circuit resistance, double-sided two-tier terminals for large conductor cross-section and busbar, switch position indicator, viewing window for labels, multifunction switch toggle with three positions: "on", "off" and "tripped", Neutral conductor position left

Mounting method:
quick fastening to mounting rail, any installation position, supply preferably from above

Applications:
Commercial and industrial installations with TT, TN-S and TN-C-S systems, where power electronics equipment is used without galvanic isolation from the mains, e.g. frequency converters, switching power supplies, high-frequency converters, photovoltaic installations and UPS equipment with frequency converters without transformers.

Hints:
suitable for use in 50 Hz AC networks, RCCBs for other frequencies available upon request, Not designed for use in direct current networks or on the output side of controlled electrical equipment such as frequency converters.