Schneider Electric C40S4TM400D ComPacT NSX400S DC 4P 400 A 100 kA TM-DC Fixed Moulded Case Circuit Breaker

The C40S4TM400D is a Schneider Electric ComPacT NSX400S DC 4-pole DC moulded case circuit breaker rated 400 A at 40 °C and 750 V DC, with a 100 kA breaking capacity (Icu) across the full DC voltage range. Its TM-DC thermal-magnetic trip unit gives adjustable overload and short-circuit protection without electronic components.

Technical Specifications

Certifications & Standards

• EN/IEC 60947-2

Selection Notes

The TM-DC trip unit gives adjustable overload protection (Ir 0.7–1×In) and adjustable magnetic short-circuit protection (Ii 2.5–5×In) without electronic components, which keeps the device simple for DC distribution or photovoltaic combiner applications. The 100 kA breaking capacity stays constant from 24 V DC up to 750 V DC because the poles connect in series for the higher-voltage ratings — the series 3-pole connection is what delivers the full 100 kA at 750 V DC. Choose the 400 A rating over the other TM-DC variants in the same frame to match the DC feeder or string combiner current.