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MERSEN FUSE IEC UL508 Switch 40A 3p M403
Mersen M403 UL508 non-fused 40 A three-pole load break switch with direct screw mounting for motor disconnect and industrial electrical isolation.
£39.23
Why Choose the Mersen M403 UL508 Load Break Switch?
The Mersen M403 is a compact and robust UL508 non-fused load break switch designed to provide dependable switching and electrical isolation for industrial machinery and low-voltage power distribution systems. Rated at 40 A and 600 V AC, it is ideal for use as a motor disconnect, branch circuit switch or line-of-sight isolator in commercial and industrial installations.
As part of the proven Mersen M-Series UL508 switch range, the M403 combines a compact footprint with rugged construction and high switching performance. Its direct screw mounting arrangement and broad selection of compatible handles and shafts provide flexibility for panel builders, OEMs and electrical contractors.
The M403 features a three-pole configuration and is capable of making and breaking loads up to 600 V AC. Its non-fused design makes it suitable where circuit protection is provided separately by fuses or circuit breakers, allowing the switch to focus on safe manual switching and reliable electrical isolation.
Key Advantages
- Compact UL508 non-fused load break switch.
- 40 A rated current for industrial applications.
- 600 V AC maximum operating voltage.
- Three-pole configuration for three-phase systems.
- Suitable as a motor disconnect and branch circuit switch.
- Robust industrial construction with multiple mounting options.
Key Features
- Mersen M-Series UL508 switch.
- 40 A rated operational current.
- 600 V AC maximum operating voltage.
- Three-pole non-fused design.
- Direct screw mounting configuration.
- Suitable for DIN rail, base or door-mounted installations with compatible accessories.
- Double-break silver-plated contacts.
- Padlockable with optional handles and shafts.
Reliable Switching for Industrial Equipment
Load break switches provide a safe and dependable means of manually disconnecting electrical equipment for maintenance, servicing and emergency isolation. Their compact construction makes them particularly suitable for machinery control panels and industrial electrical assemblies where space is limited.
The Mersen M403 is engineered for reliable switching performance while maintaining a compact footprint. Its robust design and flexible mounting options make it suitable for OEM machinery, industrial automation systems and commercial electrical installations.
Typical Applications
- Motor disconnect switches.
- Industrial machinery.
- OEM control panels.
- Branch circuit switching.
- Electrical isolation within switchboards.
- Commercial and industrial power distribution.
Technical Specifications
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| Current | 40 A | |
|---|---|---|
| Phase | Three Phase | |
| Poles | 3-pole | |
| Device Type | Fuse link | |
| Manufacturer | Mersen | |
| Series | UL508 Switch | |
| Model | M403 | |
| Reference number | C1043190 | |
| Product type | UL508 non-fused load break switch | |
| Rated current | 40 A | |
| Maximum operating voltage | 600 V AC | |
| Number of poles | 3 | |
| Mounting type | Direct screw mounting | |
| Suitable applications | Motor disconnect, branch circuit switch, electrical isolation | |
| RoHS compliant | Yes | |
| Typical weight | Approx. 0.11 kg | |
| HS Code | 85363090 | |
| Country of Manufacture | Finland |
Frequently Asked Questions
What is the Mersen M403 used for?
The M403 is used as a manual load break switch for switching and isolating electrical circuits, including motor disconnect and branch circuit applications.
What is the current rating of the M403?
The Mersen M403 has a rated operational current of 40 A.
Is the M403 a fused switch?
No. The M403 is a non-fused UL508 load break switch. Circuit protection should be provided separately using suitable protective devices.
What voltage is the M403 designed for?
The switch is designed for operation on systems up to 600 V AC.
How many poles does the M403 have?
The M403 features a three-pole configuration for switching three-phase electrical circuits.
Trusted by Electrical Professionals Worldwide
Mersen UL508 load break switches are trusted by panel builders, OEMs and industrial electricians for dependable switching, compact installation and reliable electrical isolation across a wide range of industrial applications.
