4P125

MERSEN FUSE Fourth Fusable pole for M800D 4PD800

Mersen 4PD800 fourth fusible pole accessory designed for the Mersen M800D 800 A fusible disconnect switch, enabling a compatible four-pole fused isolation assembly.

SKU: 4PD800MPN: 4PD800
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£591.44

Why Choose the Mersen 4PD800 Fourth Fusible Pole?

The Mersen 4PD800 is a genuine fourth fusible pole accessory designed for the compatible Mersen M800D fusible disconnect switch. It enables 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 M800D platform, the 4PD800 supports coordinated operation across the complete switch assembly. Its manufacturer-matched design helps maintain correct mechanical alignment, dependable switching performance and reliable circuit isolation in demanding industrial electrical systems.

Designed for the 800 A switch frame, the Mersen 4PD800 provides panel builders and electrical engineers with a practical solution for creating high-current four-pole fused disconnect assemblies. The accessory is particularly suitable for switchboards, motor control centres, machinery and industrial power distribution installations.

Key Advantages

  • Genuine Mersen fourth fusible pole accessory.
  • Designed specifically for the Mersen M800D 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 construction supports correct mechanical integration.
  • Suitable for demanding high-current power distribution systems.

Key Features

  • Mersen disconnect switch accessory range.
  • Fourth fusible pole configuration.
  • Compatible with the Mersen M800D fusible disconnect switch.
  • Designed for the 800 A switch frame.
  • Supports coordinated four-pole switching and circuit isolation.
  • Provides fuse accommodation for the additional pole.
  • Heavy-duty construction for industrial applications.
  • Designed for installation within electrical panels and switchboards.

Reliable High-Current Four-Pole Fusible Isolation

Four-pole disconnect assemblies are used where an additional conductor must be isolated and fuse-protected together with the main phase conductors. The Mersen 4PD800 adds this functionality to a compatible M800D switch, allowing coordinated switching across all four poles.

Using an original Mersen accessory helps preserve the mechanical compatibility and intended operating performance of the disconnect switch. The 4PD800 is therefore well suited to panel builders and engineers configuring high-current isolation and circuit protection equipment for industrial installations.

Typical Applications

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

Technical Specifications

Manufacturer Mersen
Model 4PD800
Product type Fourth fusible pole accessory
Compatible switch Mersen M800D
Compatible switch rating 800 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 4PD800 used for?

The Mersen 4PD800 is used to add a fourth switched and fusible pole to a compatible Mersen M800D fusible disconnect switch.

Which disconnect switch is compatible with the 4PD800?

The 4PD800 is specifically designed for use with the Mersen M800D fusible disconnect switch.

Is the Mersen 4PD800 a complete disconnect switch?

No. It is an accessory that adds a fourth fusible pole to a compatible M800D disconnect assembly. The main switch and appropriate fuse are supplied separately.

What switch rating is the 4PD800 designed for?

The accessory is designed for the compatible 800 A M800D switch frame.

Where is the Mersen 4PD800 typically installed?

It is typically fitted to an M800D switch within an industrial switchboard, motor control centre, power distribution panel 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 demanding power distribution systems.

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