Schneider Electric NSX100N Moulded Case Circuit Breaker

Product Details

NSX100N Product Description

The Schneider Electric LV429840 is the NSX100N Moulded Case Circuit Breaker (MCCB) within the Compact NSX series — a precision-engineered protection device rated for 100 A with an IEC 60947-2 breaking capacity of up to 50 kA at 415 V AC. Designed for integration into low-voltage switchgear panels, motor control centres (MCCs), and distributed control cabinets, the LV429840 delivers consistent overcurrent and short-circuit protection across demanding industrial environments. Its compact form factor and standardised DIN-rail or fixed-mount installation make it a foundational component in layered control architectures where panel space, thermal stability, and long-term reliability are non-negotiable engineering requirements.

In a complete automation architecture, protection devices such as the LV429840 do not operate in isolation. They anchor the power distribution and protection layer that feeds every downstream control element — from PLC CPU racks and I/O modules to servo drives, communication gateways, and HMI panels. The NSX100N's role is to ensure that upstream fault events are isolated before they propagate into sensitive control hardware, preserving system uptime and reducing unplanned maintenance cycles across the full installation lifecycle.

The LV429840 NSX100N is most effectively deployed as part of a coordinated low-voltage protection and control platform. In a typical MCC or control cabinet architecture, the NSX100N provides upstream feeder protection for a Schneider Electric TeSys D contactor (LC1D series) used in motor starter circuits, ensuring that short-circuit events at the motor branch do not cascade into the main busbar. Paired with a Schneider Electric Acti9 iC60N MCB on auxiliary circuits, the protection hierarchy is clearly defined across both power and control voltage levels.

At the control layer, a Modicon M340 or Modicon M580 PLC CPU rack typically governs the process logic that determines when motor feeders protected by the NSX100N are energised or de-energised. The M580's Hot Standby redundancy architecture benefits directly from reliable upstream protection — any nuisance tripping or undetected fault at the breaker level can compromise CPU rack availability. Selecting the NSX100N with appropriate Ir and Im settings, calibrated to the connected load profile, is therefore a system-level engineering decision, not merely a component selection.

For installations requiring remote monitoring and predictive maintenance, the NSX100N can be upgraded with a Micrologic trip unit and connected to a Schneider Electric PowerLogic ION7650 power meter or an EcoStruxure Power Advisor gateway. This enables real-time current, voltage, and energy data to be surfaced at the SCADA or HMI layer — typically a Magelis HMIGTO or a Vijeo Designer-based panel — without adding external current transformers or signal conditioning hardware. The result is a leaner panel design with fewer potential failure points.

In distributed I/O architectures, where Modicon STB or Advantys island bus modules extend digital and analogue I/O to field devices, the NSX100N protects the 24 V DC power supply rails feeding these remote I/O racks. A Schneider Electric ABL8 SMPS switch-mode power supply, rated at 24 V DC / 20 A, is a common companion component in such configurations. Protecting the AC input to this power supply with a correctly rated NSX100N ensures that a downstream DC bus fault does not result in loss of the entire I/O island.

For drive-intensive applications — such as variable speed drives (VSDs) in the Altivar ATV320 or ATV630 series — the NSX100N serves as the upstream Type 2 coordination breaker, selected in accordance with Schneider Electric's coordination tables to ensure that the drive's internal semiconductor protection is not exposed to fault currents beyond its withstand rating. This coordination discipline is essential in pump stations, HVAC systems, and conveyor lines where drive availability directly impacts process throughput.

Manufacturing & Assembly Lines: In automotive body shop or discrete parts manufacturing, the LV429840 protects feeder circuits supplying robot controller cabinets, servo amplifier racks, and pneumatic valve islands. Its fast magnetic trip response limits arc energy and protects downstream variable frequency drives from destructive fault currents during tooling changeovers or emergency stop sequences.

Power Distribution & Utilities: In medium-voltage substation LV distribution boards, the NSX100N is deployed as an outgoing feeder breaker for transformer secondary circuits. Its IEC 60947-2 N-category breaking capacity (50 kA) is well-suited to high-fault-level busbars in utility substations and industrial power distribution centres, where fault current levels can approach or exceed the ratings of standard MCBs.

Oil, Gas & Petrochemical: In hazardous area control rooms and safe-area marshalling cabinets, the LV429840 protects instrumentation power supplies, intrinsic safety barriers, and field junction box circuits. Its thermal-magnetic trip characteristic provides reliable protection for resistive and mixed loads typical of process instrumentation loops without nuisance tripping under normal operating conditions.

Water & Wastewater Treatment: Pump station MCCs in water treatment facilities rely on coordinated protection schemes where the NSX100N acts as the incomer or sub-feeder breaker above TeSys contactors and overload relays. Its compact dimensions allow high-density panel layouts in prefabricated kiosk substations where internal volume is constrained.

Mining & Metallurgy: In underground or surface mining electrical rooms, the NSX100N's robust thermal-magnetic trip unit withstands the vibration, dust, and humidity conditions common to mining environments. It is frequently specified in conveyor drive panels, crusher motor starters, and ventilation fan control boards where continuous duty cycles demand reliable overcurrent protection.

Q1: Is the LV429840 NSX100N compatible with Schneider Electric's TeSys D contactor for Type 2 coordination in motor starter applications?Yes. Schneider Electric publishes coordination tables confirming Type 2 coordination between the NSX100N (LV429840) and TeSys D contactors (LC1D series) up to specific motor ratings. Type 2 coordination ensures that under short-circuit conditions, neither the contactor nor the overload relay sustains damage that would prevent continued operation after the fault is cleared. Always verify the specific contactor frame size and overload relay setting against the published coordination table for the connected motor kW rating and supply voltage.

Q2: Can the NSX100N be retrofitted with a Micrologic trip unit for Modbus communication and remote diagnostics?The standard LV429840 ships with a thermal-magnetic (TM-D) trip unit. Upgrading to a Micrologic electronic trip unit requires selecting the appropriate NSX100N Micrologic variant at the time of order, as the trip unit is factory-fitted and not field-swappable on all configurations. For installations requiring Modbus RTU or Ethernet/IP communication, specify the NSX100N with Micrologic 2.2 or 5.2 trip units and the corresponding communication module. Consult the Compact NSX catalogue for compatible accessory part numbers before finalising the panel BOM.

Q3: What warranty and supply assurance does NANKMOS provide for the LV429840?All LV429840 units supplied by NANKMOS are covered by a 12-Month Warranty from the date of shipment, covering manufacturing defects and functional failures under normal operating conditions. Units are sourced from authorised distribution channels and undergo pre-shipment functional verification. NANKMOS maintains buffer stock of high-demand Compact NSX variants to support urgent project timelines and MRO replacement requirements. For volume orders or scheduled project deliveries, contact [email protected] to confirm lead times and reserve allocation.