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MERSEN FUSE CC 4,5 GRB 72 EF 0550 D72GB45V550EF

MERSEN FUSE CC 4,5 GRB 72 EF 0550 D72GB45V550EF

High-speed fuse offering fast, reliable protection for demanding DC circuits, rated at 450V DC (IEC) and 500V DC (UL) with a robust 550A breaking capacity. Features striker indication and bolted mounting.

SKU: Q302694Alt SKU: D72GB45V550EFMPN: Q302694
Price
List Price £319.36 ex VAT
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£319.36
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Sold in packs of 3

£319.36

Why Choose the Mersen Q302694 Protistor® High-Speed Fuse?

The Mersen Q302694 (D72GB45V550EF) is a premium Protistor® square body high-speed semiconductor fuse engineered to provide rapid fault protection for sensitive power electronic equipment. Designed for demanding DC applications, it protects semiconductors including IGBTs, thyristors, GTOs and power diodes against damaging short-circuit currents, helping maximise system reliability and minimise costly downtime.

Part of the proven Protistor® Size 72 gR series, the Q302694 features low let-through energy (I²t), high interrupting capability and silver fuse elements embedded in solidified sand for exceptional arc control. The fuse incorporates open slot blade terminals with an integrated striker, allowing easy installation and remote indication when operated.

With a 550 A current rating, 450 V DC (IEC) and 500 V DC (UL) voltage ratings, the Q302694 is ideally suited to industrial drives, battery energy storage systems, renewable energy converters, UPS equipment and other high-power semiconductor applications.

Key Advantages

  • High-speed gR semiconductor protection fuse.
  • 550 A current rating.
  • 450 V DC IEC / 500 V DC UL rated voltage.
  • Protects IGBTs, thyristors, GTOs and power diodes.
  • Low I²t minimises damage during fault conditions.
  • Integrated striker for remote fuse indication.
  • Open slot blade terminals simplify installation.

Key Features

  • Mersen Protistor® Size 72 gR series.
  • Manufacturer part number: Q302694.
  • Catalogue number: D72GB45V550EF.
  • 550 A rated current.
  • 450 V DC IEC / 500 V DC UL.
  • Square body high-speed semiconductor fuse.
  • Open slot blade connections.
  • Integrated striker indicator.

Reliable Protection for Modern Power Electronics

High-speed semiconductor fuses are specifically designed to protect expensive electronic power devices against destructive fault currents. Their extremely fast operation limits thermal and electrical stress, helping improve equipment reliability, reduce repair costs and extend the service life of critical power conversion equipment.

Mersen Protistor® semiconductor fuses are widely specified for industrial automation, renewable energy systems, battery storage installations, UPS equipment and power converters where dependable semiconductor protection is essential.

Typical Applications

  • Industrial DC drives.
  • Power converters and rectifiers.
  • Battery energy storage systems.
  • Renewable energy installations.
  • UPS and critical power systems.
  • Industrial automation equipment.
  • Protection of IGBTs, GTOs and thyristors.

Technical Specifications

Item number Q302694
Catalogue No D72GB45V550EF
Description Square Body High-Speed Fuse Protistor® Size 72 gR 450VDC IEC 500VDC UL 550A With Striker Open Slot Blades
EAN/UPC Code 3605340355321
Rated voltage DC UL 500 V
Rated voltage DC IEC 450 V
Ampere Rating 550 A
RoHS Compliant Yes
AC or DC DC
Speed/Characteristic gR
Fuse Size 72
Mounting Bolted
Melting I2t 84050 A²s
Indication System Yes
Indication System Type Striker
Connection/Terminal Material Silver-Plated Copper
Connection/Terminal Type Open Slot Blades
Product Width 59 mm
Product Length 133.4 mm
Product Height 63 mm
Sell Pack Quantity 3 EA
Sell Pack Weight 2.274 kg
Sell Pack Width 157 mm
Sell Pack Length 202 mm
Sell Pack Height 80 mm
Product group Semiconductor Protection Fuses
Body/Insulating Material Ceramic
Product Weight 0.758 kg
Power Dissipation at Rated Current Value 72 W
HS Code 85361090
Country of Manufacture France
Fuse Type Semiconductor
Fuse Class gR
Voltage 500 V

Frequently Asked Questions

What is the Mersen Q302694 used for?

The Mersen Q302694 is a high-speed semiconductor fuse designed to protect sensitive power electronic devices such as IGBTs, thyristors, GTOs and power diodes from damaging short-circuit currents.

What is the current rating of this fuse?

The fuse has a 550 A rated current.

What voltage is the Q302694 rated for?

The fuse is rated for 450 V DC (IEC) and 500 V DC (UL).

Does this fuse include a striker?

Yes. The Q302694 incorporates an integrated striker that can be used for remote fuse indication or operation of an auxiliary microswitch.

Where is the Q302694 commonly installed?

It is commonly installed in industrial drives, renewable energy equipment, battery storage systems, UPS installations and other semiconductor-based power conversion equipment.

Trusted for Semiconductor Protection

Mersen Protistor® semiconductor fuses are trusted worldwide by OEMs, panel builders and industrial engineers for delivering rapid fault protection, low energy let-through and dependable long-term performance.

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