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Engineered for demanding industrial environments, this Protistor® high-speed fuse delivers rapid, reliable protection for sensitive power semiconductor devices, ensuring minimal energy let-through and enhanced system safety.
£92.08
The Mersen G300478 is a genuine Protistor® Size 31 aR high-speed semiconductor fuse designed to provide maximum protection for today's power electronic equipment. Engineered for demanding industrial environments, this square body fuse delivers ultra-fast fault interruption to protect sensitive semiconductor devices including IGBTs, thyristors and diodes from damaging short-circuit conditions.
With a 500 A current rating and 690 V AC (IEC) / 700 V AC (UL) voltage ratings, the G300478 is ideal for industrial drives, UPS systems, DC power systems and power conversion equipment. Its ultra-fast aR operating characteristic helps minimise let-through energy, reducing equipment damage while improving system reliability and availability.
Supplied under manufacturer part number G300478 and catalogue number A070UD31TTI500, this fuse features flush ends with UNC threaded terminals and an integrated striker indication system for straightforward monitoring and maintenance. Silver-plated contacts and a high interrupting capacity make it suitable for demanding industrial applications.
High-speed semiconductor fuses are specifically engineered to protect sensitive electronic power devices that require extremely rapid fault interruption. Their low let-through energy helps safeguard expensive semiconductor assemblies while maintaining reliable system operation and reducing maintenance costs.
The Mersen Protistor® range is widely specified for industrial automation, motor drives, UPS systems, renewable energy installations and DC power conversion equipment where dependable semiconductor protection is essential.
Tick the specs you need, then view products that match.
| Fuse Indication | Striker | |
|---|---|---|
| Fuse Type | Semiconductor | |
| Fuse Class | aR | |
| Voltage | 690 V | |
| Item number | G300478 | |
| Catalogue No | A070UD31TTI500 | |
| Description | Square Body High-Speed Fuse Protistor® Size 31 aR 690VAC IEC 700VAC UL 500A With Striker Flush ends UNC threads | |
| EAN/UPC Code | 3605340329070 | |
| Rated voltage AC UL | 700 V | |
| Rated voltage AC IEC | 690 V | |
| Ampere Rating | 500 A | |
| RoHS Compliant | Yes | |
| AC or DC | AC | |
| Speed/Characteristic | aR | |
| Fuse Size | 31 | |
| Mounting | Bolted | |
| Clearing I2t At Rated Voltage | 215000 A²s | |
| Melting I2t | 37000 A²s | |
| AC Max I.R./Breaking Capacity | I1: 200 kA | |
| Indication System | Yes | |
| Indication System Type | Striker | |
| Connection/Terminal Material | Silver-Plated Brass | |
| Connection/Terminal Type | Flush ends | |
| Product Width | 51 mm | |
| Product Length | 50.6 mm | |
| Product Height | 56.5 mm | |
| Sell Pack Quantity | 3 EA | |
| Sell Pack Weight | 1.155 kg | |
| Sell Pack Width | 85 mm | |
| Sell Pack Length | 168 mm | |
| Sell Pack Height | 65 mm | |
| Product group | Semiconductor Protection Fuses | |
| Body/Insulating Material | Ceramic | |
| Product Weight | 0.385 kg | |
| Power Dissipation at Rated Current Value | 70 W | |
| HS Code | 85361090 | |
| Country of Manufacture | France |
The Mersen G300478 is a high-speed semiconductor fuse designed to protect power electronic equipment against short-circuit and overcurrent faults.
The fuse has a 500 A current rating.
It is rated for 690 V AC (IEC) and 700 V AC (UL).
The fuse features flush-end UNC threaded terminals with an integrated striker indication system.
It is commonly installed in industrial drives, UPS systems, DC power systems and other semiconductor protection applications.
Mersen Protistor® semiconductor fuses are trusted by OEMs, panel builders and maintenance engineers worldwide for reliable protection of critical power electronic equipment in demanding industrial environments.
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