1. Sarrera
This manual provides essential information for the safe and effective installation, operation, and maintenance of the Legrand 408700-40A Four Pole 10kA C Curve 415V AC DX3 Miniature Circuit Breaker (MCB). Please read this manual thoroughly before installation or use to ensure proper functionality and safety.
2. Segurtasun informazioa
OHARRA: Deskarga elektrikoaren arriskua. Instalazioa eta mantentze-lanak langile kualifikatuek soilik egin behar dituzte.
- Disconnect power before working on electrical circuits.
- Ziurtatu sistema elektrikoaren lurreratze egokia.
- Erabili babes pertsonaleko ekipamendu (EPI) egokia, eskularru isolatzaileak eta segurtasun-betaurrekoak barne.
- Do not operate the MCB if it appears damaged or shows signs of wear.
- Adhere to all local and national electrical codes and regulations during installation and use.
3. Produktua amaitu daview
The Legrand 408700-40A is a Four Pole Miniature Circuit Breaker designed for protection against overcurrents and short circuits in electrical installations. It features a 10kA breaking capacity and a C-curve tripping characteristic, making it suitable for general applications with moderate inrush currents.

Irudia: Aurrealdea view of the Legrand 408700-40A Four Pole Miniature Circuit Breaker, showing the toggle switch and product labeling.
Ezaugarri nagusiak:
- Four Pole (FP) configuration for multi-phase protection.
- 40 Amps current rating.
- 10 kA breaking capacity for robust fault interruption.
- C-curve tripping characteristic, suitable for resistive and inductive loads.
- Rated for 415V AC systems.
4. Instalazioa
Installation must be carried out by a qualified electrician in accordance with relevant electrical standards.
Aurrebaldintzak:
- Ensure the main power supply to the installation is completely OFF and locked out.
- Verify that the MCB specifications (current rating, breaking capacity, curve type, voltage) match the circuit requirements.
- Erabili isolamendu egokia duten tresnak lan elektrikoetarako.
Instalazio urratsak:
- Muntaketa: Securely mount the MCB onto a standard 35mm DIN rail within an appropriate electrical enclosure. Ensure it is firmly clipped into place.
- Wiring - Incoming: Connect the incoming phase conductors (L1, L2, L3, L4) to the upper terminals of the MCB. Ensure correct phase sequence and secure connection.
- Wiring - Outgoing: Connect the outgoing phase conductors to the lower terminals of the MCB.
- Terminalen estutzea: Tighten all terminal screws to the recommended torque specified on the device or in the technical data sheet. Overtightening or undertightening can lead to poor contact and overheating.
- Egiaztapena: Double-check all connections for security, correct wiring, and absence of loose strands.
- Itxitura: Close the electrical enclosure securely.
- Energia berreskuratzea: Restore power to the main supply.
5. Funtzionamendua
The MCB features a simple toggle switch for manual operation and visual indication of its status.
- ON Position (Toggle Up): The circuit is closed, allowing electrical current to flow through the MCB.
- OFF Position (Toggle Down): The circuit is open, disconnecting power. This is the manual OFF position.
- TRIPPED Position (Toggle Middle): The MCB has automatically opened the circuit due to an overcurrent or short circuit. This is an automatic OFF position.
Jauzi egin duen MCB bat berrezartzea:
- Identifikatu kausa: Before resetting, identify and rectify the cause of the trip (e.g., remove overloaded devices, fix short circuits, replace faulty appliances).
- Eskuz OFF: Move the toggle switch fully to the OFF (down) position. This resets the internal tripping mechanism.
- Berrezarri boterea: Move the toggle switch to the ON (up) position to restore power to the circuit.
- Ihesaldi iraunkorrak: If the MCB trips immediately again, do not attempt to reset it repeatedly. This indicates a persistent fault that requires professional investigation by a qualified electrician.
6. Mantentzea
Legrand MCBs are designed for long-term reliability and are generally maintenance-free. However, periodic inspection is recommended to ensure continued safe operation.
- Ikuskapen bisuala (urtero): With power disconnected, visually inspect the MCB for any signs of physical damage, discoloration, burn marks, loose connections, or evidence of overheating.
- Garbiketa: If necessary, gently clean the exterior of the MCB with a dry, lint-free cloth. Do not use solvents, abrasive cleaners, or liquids.
- Terminalaren estutasuna: Periodically check and re-tighten terminal screws if necessary, ensuring the main power supply is disconnected before performing this task.
WARNING: Do not attempt to repair a damaged or malfunctioning MCB. Replace it with an identical Legrand model to ensure continued protection and compliance with safety standards.
7. Arazoak
This section provides solutions to common issues encountered with Miniature Circuit Breakers.
| Arazoa | Kausa posiblea | Irtenbidea |
|---|---|---|
| MCB trips frequently | Overload on the circuit, short circuit, faulty appliance, incorrect MCB rating for the load. | Reduce the load on the circuit, check for and rectify short circuits, inspect appliances for faults, verify if the MCB rating is appropriate for the connected load. |
| MCB does not reset | Persistent fault (e.g., continuous short circuit or severe overload), internal damage to the MCB. | Ensure the fault is completely cleared. If still unable to reset after clearing the fault, the MCB may be damaged and requires replacement by a qualified electrician. |
| MCB feels hot to the touch | Loose terminal connections, continuous overload, undersized wiring for the circuit. | With power off, check and tighten all terminal connections. Reduce the load on the circuit. Consult an electrician to assess wiring size if overheating persists. |
8. Zehaztapenak
- Marka: Legrand
- Modelo zenbakia: 408700
- Mota: Miniaturazko etengailua (MCB)
- Poloak: Four Pole (FP)
- Uneko balorazioa: 40 Amps
- Hausteko gaitasuna: 10 kA
- Kurba mota: C-Curve
- liburukiatage Balorazioa: 415 V AC
- Izen orokorra: etengailu-panelen
- Kopuru garbia: 1.00 zenbaketa
- Lehen eskuragarri dagoen data: 22ko ekainaren 2022a
9. Bermea eta Laguntza
For detailed warranty information, technical support, or service inquiries, please refer to the official Legrand website or contact your local authorized Legrand distributor. It is recommended to retain your purchase receipt as proof of purchase for any warranty claims.
Legrand Ofiziala Webgunea: www.legrand.co.in (Mesedez, egiaztatu eskualdeko zuzena) website for your location.)





