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MERSEN FUSE 400B4 F226325

MERSEN FUSE 400B4 F226325

The BTMF42V400 fuse-link is engineered to British Standard IEC BS88, offering reliable circuit protection for industrial and commercial low voltage installations. Suitable for use at 415VAC and 240VDC, it delivers consistent performance in demanding environments.

SKU: BTMF42V400Alt SKU: BTMF42V400MPN: F226325
Price
List Price £80.63 ex VAT
Your Price (ex VAT)
£80.63
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Manufacturer Lead Time

£80.63

Why Choose the Mersen BTMF42V400 Battery Fuse?

The Mersen BTMF42V400 is a compact, high-current 400 A battery fuse designed to provide dependable overcurrent and short-circuit protection in low-voltage DC electrical systems. Manufactured by Mersen, it is suitable for battery-powered equipment requiring reliable protection close to the electrical power source.

This fuse helps protect batteries, conductors and connected electrical equipment by interrupting excessive current during qualifying fault conditions. Its high-current construction supports demanding power distribution applications while helping reduce the risk of cable damage, overheating and equipment failure.

With a rated current of 400 A and a maximum voltage rating of 42 V DC, the BTMF42V400 is suitable for automotive, commercial vehicle, marine and specialist low-voltage power systems. Its compact mounting format allows it to be integrated into battery distribution assemblies where space and dependable electrical performance are important.

Key Advantages

  • Compact battery fuse for high-current DC circuit protection.
  • 400 A current rating for demanding electrical loads.
  • 42 V DC voltage rating for low-voltage battery systems.
  • Helps protect batteries, cables and connected electrical equipment.
  • Designed for installation close to the battery or DC power source.
  • High-current construction suitable for power distribution applications.

Key Features

  • Mersen BTMF battery fuse series.
  • 400 A rated current.
  • 42 V DC rated voltage.
  • Designed for overcurrent and short-circuit protection.
  • Compact format for low-voltage battery distribution systems.
  • Suitable for high-current DC cables and connected equipment.
  • Non-resettable fuse element for reliable fault interruption.
  • Suitable for automotive, transport, marine and industrial applications.

Reliable Protection for High-Current Battery Circuits

Battery fuses such as the Mersen BTMF42V400 are designed to disconnect an electrical circuit when current exceeds safe operating levels. Installing the fuse close to the battery helps minimise the length of unprotected cabling and reduces the potential for damage caused by short circuits.

The BTMF42V400 is suitable for circuits carrying substantial operating current, including battery power distribution, auxiliary power systems and high-load DC equipment. Its 400 A rating makes it appropriate for applications that require robust protection without using a physically oversized circuit protection device.

Typical Applications

  • Automotive battery and power distribution systems.
  • Commercial and specialist vehicle electrical systems.
  • Marine battery installations.
  • Auxiliary battery and inverter circuits.
  • Industrial machinery with low-voltage DC supplies.
  • High-current cable and equipment protection.

Technical Specifications

Item number F226325
Catalogue No BTMF42V400
Description British Standard fuse-link IEC BS88 gG Type B4 415VAC 240VDC 400A BTMF Central Bolted Tag
EAN/UPC Code 3605340268027
Rated voltage AC IEC 415 V
Rated voltage DC IEC 240 V
Ampere Rating 400 A
RoHS Compliant Yes
AC or DC AC/DC
Speed/Characteristic gG
Fuse Size B4
Mounting Bolted
Clearing I2t At Rated Voltage 1414000 A²s
Melting I2t 505000 A²s
AC Max I.R./Breaking Capacity I1: 80 kA
Max. Rated Breaking Capacity DC 40 kA
Connection/Terminal Material Tin-Plated Copper
Connection/Terminal Type Central Bolted Tag
Product Diameter 59.1 mm
Product Length 138 mm
Sell Pack Quantity 1 EA
Sell Pack Weight 0.612 kg
Sell Pack Width 53 mm
Sell Pack Length 139 mm
Sell Pack Height 52 mm
Product group Low Voltage IEC Fuses
Body/Insulating Material Ceramic
Product Weight 0.612 kg
Power Dissipation at Rated Current Value 38 W
HS Code 85361090
Country of Manufacture India
Fuse Class gG
Voltage 415 V

Frequently Asked Questions

What is the Mersen BTMF42V400 used for?

The BTMF42V400 is used to protect high-current battery circuits, cables and connected electrical equipment against overload and short-circuit faults.

What is the current rating of this fuse?

The Mersen BTMF42V400 has a rated current of 400 A.

What voltage is the BTMF42V400 rated for?

The fuse is designed for low-voltage DC electrical systems operating at up to 42 V DC.

Where should the BTMF42V400 be installed?

The fuse should normally be installed as close as practical to the battery or DC power source using compatible fuse mounting equipment.

Can the Mersen BTMF42V400 be reset after it operates?

No. The BTMF42V400 is a non-resettable fuse and must be replaced with a correctly rated equivalent after it has interrupted an electrical fault.

Trusted Electrical Protection from Mersen

Mersen battery fuse products are used in automotive, transportation, marine and industrial DC systems to provide dependable protection for batteries, power cables and critical electrical equipment.

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