The A070UD31LI800 fuse delivers reliable circuit protection for high-speed applications up to 690VAC (IEC) and 700VAC (UL), ensuring rapid clearance of fault currents to safeguard sensitive industrial equipment. Its robust 800A rating and square body design optimise thermal and electrical performance for demanding environments.
£222.94
The Mersen F300707 (catalogue number A070UD31LI800) is a premium Protistor® square body high-speed semiconductor protection fuse engineered to provide exceptional protection for modern power electronic equipment. Designed specifically to safeguard IGBTs, thyristors, diodes and semiconductor modules, it delivers ultra-fast fault interruption to minimise damage during severe short-circuit conditions.
As part of the proven Mersen Protistor® Size 31 aR series, this fuse features low let-through energy (I²t), silver-plated contact surfaces and a robust square body construction filled with solidified sand for superior arc control. The integrated striker indicator can operate an optional microswitch for remote status indication, simplifying maintenance and improving system monitoring.
With a rated current of 800 A and voltage ratings of 690 V AC (IEC) and 700 V AC (UL), the F300707 is ideally suited for industrial drives, power converters, UPS systems, renewable energy equipment and other demanding semiconductor protection applications.
The Mersen F300707 is designed to interrupt high fault currents before they can damage expensive semiconductor devices. Its ultra-fast operating characteristics and low energy let-through help maximise equipment reliability while reducing maintenance costs and unplanned downtime.
This Protistor® fuse is widely used throughout industrial automation, renewable energy systems and power conversion equipment where dependable protection of semiconductor devices is essential for safe and reliable operation.
| Item number | F300707 |
|---|---|
| Catalogue No | A070UD31LI800 |
| Description | Square Body High-Speed Fuse Protistor® Size 31 aR 690VAC IEC 700VAC UL 800A With Striker Slotted Blades long |
| EAN/UPC Code | 3605340332490 |
| Rated voltage AC UL | 700 V |
| Rated voltage AC IEC | 690 V |
| Ampere Rating | 800 A |
| RoHS Compliant | Yes |
| AC or DC | AC |
| Speed/Characteristic | aR |
| Fuse Size | 31 |
| Mounting | Bolted |
| Clearing I2t At Rated Voltage | 880000 A²s |
| Melting I2t | 140000 A²s |
| AC Max I.R./Breaking Capacity | I1: 200 kA |
| Indication System | Yes |
| Indication System Type | Striker |
| Connection/Terminal Material | Silver-Plated Copper |
| Connection/Terminal Type | Slotted Blades |
| Product Width | 51 mm |
| Product Length | 148.6 mm |
| Product Height | 56.5 mm |
| Sell Pack Quantity | 3 EA |
| Sell Pack Weight | 1.2519 kg |
| Sell Pack Width | 155 mm |
| Sell Pack Length | 165 mm |
| Sell Pack Height | 60 mm |
| Product group | Semiconductor Protection Fuses |
| Body/Insulating Material | Ceramic |
| Product Weight | 0.4173 kg |
| Power Dissipation at Rated Current Value | 120 W |
| HS Code | 85361090 |
| Country of Manufacture | France |
The F300707 is a high-speed semiconductor fuse designed to protect IGBTs, thyristors, diodes and other power electronic devices against damaging short-circuit currents.
This fuse has a 800 A current rating.
The fuse is rated for 690 V AC (IEC) and 700 V AC (UL).
The aR characteristic identifies an ultra-fast semiconductor protection fuse designed specifically to protect power electronic devices from short-circuit faults.
The F300707 is commonly installed in industrial drives, power converters, UPS equipment, renewable energy systems and other high-power semiconductor applications.
Mersen Protistor® semiconductor fuses are trusted worldwide by electrical engineers, OEMs and industrial manufacturers for protecting high-value semiconductor equipment in demanding industrial applications.
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LED Controls is a specialist distributor of factory automation and industrial controls, supplying OEMs, machine builders, panel builders and end users throughout the UK and worldwide. As a trusted UK distributor for many of the world’s leading automation manufacturers, we provide industrial control products, technical expertise and bespoke automation solutions backed by outstanding customer service.
2025 has been a big year for LED Controls, and our blog has expanded accordingly. We've covered a wide range of topics across industrial control and factory automation this year. From core technology explainers and new product releases to panel building best practice...
2025 has been a big year for LED Controls, and our blog has expanded accordingly. We've covered a wide range of topics across industrial control and factory automation this year. From core technology explainers and new product releases to panel building best practice...