4P125

MERSEN FUSE Fourth Fusable pole for M400D 4PD400

Mersen 4PD400 fourth fusible pole accessory designed for the Mersen M400D 400 A fusible disconnect switch, enabling a compatible four-pole fused isolation assembly.

SKU: 4PD400MPN: 4PD400
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£412.19

Why Choose the Mersen 4PD400 Fourth Fusible Pole?

The Mersen 4PD400 is a genuine fourth fusible pole accessory designed for the compatible Mersen M400D fusible disconnect switch. It allows a standard three-pole disconnect assembly to be expanded into a four-pole configuration, providing switched and fuse-protected isolation for an additional conductor.

Engineered for direct integration with the M400D switch platform, the 4PD400 supports dependable mechanical operation and coordinated switching across the complete assembly. It provides panel builders and electrical engineers with a practical way to configure four-pole fused isolation without replacing the main disconnect switch.

Designed for the 400 A switch frame, the Mersen 4PD400 is suitable for demanding industrial power distribution, machinery and control-panel applications. Its manufacturer-matched construction helps ensure correct fitment, reliable operation and long-term performance within compatible Mersen switchgear assemblies.

Key Advantages

  • Genuine Mersen fourth fusible pole accessory.
  • Designed specifically for the Mersen M400D disconnect switch.
  • Expands a compatible three-pole switch into a four-pole assembly.
  • Provides switched and fuse-protected isolation for an additional conductor.
  • Manufacturer-matched design supports reliable mechanical integration.
  • Suitable for high-current industrial distribution systems.

Key Features

  • Mersen disconnect switch accessory range.
  • Fourth fusible pole configuration.
  • Compatible with the Mersen M400D fusible disconnect switch.
  • Designed for the 400 A switch frame.
  • Supports coordinated four-pole switching and circuit isolation.
  • Includes provision for fuse protection on the additional pole.
  • Industrial-grade construction for dependable service.
  • Designed for installation within electrical panels and switchboards.

Reliable Four-Pole Fusible Isolation

Four-pole disconnect assemblies are used where an additional conductor must be isolated together with the primary phase conductors. The Mersen 4PD400 adds a fourth switched and fusible pole to a compatible M400D assembly, helping provide coordinated isolation and circuit protection across all required conductors.

Using an original Mersen accessory helps maintain the correct alignment, mechanical compatibility and switching operation of the disconnect assembly. This makes the 4PD400 a dependable solution for panel builders and engineers configuring high-current fused isolation equipment.

Typical Applications

  • Industrial power distribution panels.
  • Main electrical switchboards.
  • Motor control centres.
  • OEM machinery and production systems.
  • Commercial power distribution equipment.
  • Four-pole fused isolation assemblies.

Technical Specifications

Manufacturer Mersen
Model 4PD400
Product type Fourth fusible pole accessory
Compatible switch Mersen M400D
Compatible switch rating 400 A
Pole function Additional fourth switched and fusible pole
Switch type Fusible disconnect switch
Application Three-pole to four-pole switch expansion
Mounting type Direct mounting to compatible switch assembly
Installation location Electrical panel, cabinet or switchboard

Frequently Asked Questions

What is the Mersen 4PD400 used for?

The Mersen 4PD400 is used to add a fourth switched and fusible pole to a compatible Mersen M400D fusible disconnect switch.

Which disconnect switch is compatible with the 4PD400?

The 4PD400 is specifically designed for use with the Mersen M400D fusible disconnect switch.

Is the Mersen 4PD400 a complete disconnect switch?

No. It is an accessory that adds a fourth fusible pole to a compatible M400D disconnect assembly. The main switch and required fuses are supplied separately.

What switch rating is the 4PD400 designed for?

The accessory is designed for the compatible 400 A M400D switch frame.

Where is the Mersen 4PD400 typically installed?

It is typically fitted to an M400D switch within an industrial control panel, switchboard, motor control centre or machinery electrical cabinet.

Trusted by Panel Builders Worldwide

Mersen disconnect switches and accessories are specified by panel builders, electrical engineers and OEM manufacturers for dependable circuit isolation, coordinated fuse protection and reliable performance in industrial power distribution systems.

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