OS125FP-A ABB 125A 4-Pole IP65 Steel Enclosed Switch Fuse

Why Choose the ABB OS125FP-A 125A 4-Pole IP65 Steel Enclosed Switch Fuse?

The ABB OS125FP-A is a heavy-duty 125 A four-pole steel enclosed switch fuse designed for dependable electrical isolation, manual load switching and fuse-based circuit protection in industrial and commercial low-voltage installations. Part of ABB's OS enclosed switch fuse range, it combines a robust switch-disconnector mechanism with BS88 fuse compatibility in a durable metal enclosure.

Featuring a 125 A current rating, a four-pole switching arrangement and an IP65-rated mild steel enclosure, the OS125FP-A provides a practical solution for electrical distribution systems requiring local isolation and fused protection. Its four-pole construction is particularly useful where all four conductors must be switched in accordance with the installation design.

The unit is housed in a powder-coated steel enclosure finished in RAL 7035 light grey, measuring 400 × 300 × 150 mm. It incorporates a hinged access door with a double-bit lock, removable top and bottom gland plates, and a padlockable pistol-grip operating handle. These features support convenient installation, cable management and controlled access to the internal switch fuse assembly.

Designed to accommodate BS88 fuse-link sizes A2 and A3, the OS125FP-A is suitable for appropriately rated industrial and commercial distribution circuits. ABB's enclosed switch fuse range is supplied with fuse links, although the fitted fuse rating and type should always be confirmed against the installation requirements and the supplied product documentation.

Key Advantages

• 125 A rated current for suitable industrial and commercial electrical distribution applications.
• Four-pole switch fuse configuration supports simultaneous isolation of four conductors.
• Integrated fuse-switching arrangement combines manual disconnection with appropriately selected fuse protection.
• IP65-rated steel enclosure provides protection against dust ingress and water jets when correctly installed.
• Powder-coated mild steel construction offers mechanical durability in demanding environments.
• RAL 7035 light grey finish provides a professional appearance suitable for electrical plant rooms and industrial facilities.
• Padlockable pistol-grip operating handle supports controlled isolation during maintenance.
• Hinged access door provides convenient access for authorised inspection and fuse replacement.
• Double-bit door lock helps restrict access to the internal electrical components.
• Removable top and bottom gland plates offer flexibility when preparing cable entries.
• BS88 A2/A3 fuse compatibility supports the selection of suitable fuse links for the protected circuit.
• Incoming terminal shrouds provide additional protection against accidental contact with incoming terminals.
• Surface-mounted construction allows installation on suitable walls and supporting structures.
• ABB OS switch fuse technology provides a dependable solution for fused electrical isolation.

Key Features

• ABB OS enclosed switch fuse series.
• 125 A nominal current rating.
• Four-pole (4P) switching configuration.
• Fused switch-disconnector construction.
• BS88 fuse-link compatibility.
• Suitable fuse sizes: A2 and A3.
• IP65 enclosure protection rating.
• Mild steel enclosure with powder-coated finish.
• RAL 7035 light grey enclosure colour.
• Manual ON/OFF switching.
• Padlockable pistol-grip handle.
• Hinged enclosure door.
• Double-bit door locking mechanism.
• Removable top and bottom cable gland plates.
• Incoming terminal shrouds.
• Surface-mounted installation.
• 55 kW AC-23A switching power at 400 V AC.
• 500 V operational voltage specification.
• 400 × 300 × 150 mm enclosure dimensions.
• Suitable for industrial electrical distribution and isolation.

Technical Specifications

• Manufacturer: ABB
• Product range: OS Enclosed Switch Fuses
• Model: OS125FP-A
• ABB order code: OS125FP-A
• ABB product group: 311019-Metal Enclosed (Loadbreak)
• Product type: Steel enclosed switch fuse
• Switching arrangement: Fused switch-disconnector
• Rated current: 125 A
• Number of poles: 4
• Rated operational voltage: 500 V AC
• AC-23A motor switching power at 400 V AC: 55 kW
• Fuse standard: BS88
• Compatible fuse sizes: A2 / A3
• Fuse-link arrangement: Suitable BS88 fuse links
• Operating mechanism: Manual pistol-grip handle
• Switching positions: ON / OFF
• Padlocking facility: Yes
• Enclosure material: Mild steel
• Enclosure finish: Powder coated
• Enclosure colour: RAL 7035 light grey
• Enclosure protection rating: IP65
• Enclosure door: Hinged
• Door locking arrangement: Double-bit lock
• Cable entry arrangement: Removable gland plates
• Gland plate positions: Top and bottom
• Incoming terminal protection: Terminal shrouds
• Mounting type: Surface mounting
• Enclosure height: 400 mm
• Enclosure width: 300 mm
• Enclosure depth: 150 mm
• Dimensions (H × W × D): 400 × 300 × 150 mm
• Optional mounting accessory: AA1206 wall mounting brackets
• Typical applications: Fused isolation and protection of low-voltage distribution circuits
• Relevant switch fuse standard: IEC 60947-3

Reliable Four-Pole Fused Isolation for Electrical Distribution Systems

The ABB OS125FP-A combines a manual switch-disconnector with fuse-link protection in a single enclosed assembly. This arrangement allows operators to disconnect the electrical supply while providing a location for appropriately rated fuses to protect the connected circuit against overcurrent and short-circuit conditions. The level of protection depends on the installed fuse links and the electrical system design.

Its four-pole switching configuration supports installations requiring simultaneous switching of four conductors. This can be useful in three-phase distribution systems where neutral switching is specified. The exact switching and protection arrangement must be selected according to the earthing system, circuit design and applicable electrical regulations.

The padlockable pistol-grip handle provides clear manual operation and supports controlled isolation procedures. When the switch is secured in the OFF position, authorised personnel can carry out maintenance in accordance with site lockout procedures. Electrical isolation must always be verified before work begins, and the fuse-switch assembly must not be treated as a substitute for safe working practices.

The IP65 powder-coated mild steel enclosure is designed to protect the internal switch fuse mechanism from dust and water jets when correctly installed. Its hinged door and double-bit lock provide convenient access for authorised personnel, while the removable gland plates allow suitable cable entries to be prepared for the incoming and outgoing conductors.

With a 400 × 300 × 150 mm enclosure, the OS125FP-A provides space for the switch fuse assembly and cable terminations within a surface-mounted steel housing. ABB lists compatible wall mounting brackets under accessory reference AA1206, allowing additional mounting flexibility where required.

The switch fuse is designed for use with BS88 A2/A3 fuse links. Correct fuse selection is essential to ensure suitable current rating, breaking capacity, discrimination and protection of the connected cables and equipment. The fuse rating should not exceed the permissible ratings of the switch fuse assembly or the electrical installation.

Typical Applications

• Industrial low-voltage electrical distribution systems.
• Four-pole fused isolation of three-phase circuits.
• Commercial electrical distribution installations.
• Industrial machinery supply circuits.
• Electrical plant rooms and switchgear installations.
• Manufacturing and production facilities.
• Motor supply and machinery feeder circuits.
• Industrial pumps and pumping stations.
• Heating, ventilation and air conditioning installations.
• Commercial building services equipment.
• Electrical sub-distribution and local isolation points.
• Water treatment and process plant installations.
• OEM electrical distribution equipment.
• Industrial maintenance and service isolation applications.