High-speed Protistor® fuse delivering rapid fault response at 690VAC (IEC) and 700VAC (UL) for semiconductor protection up to 400A with striker indication and flush ends with UNC threads.
£129.98
The Mersen T300581 is an industrial electrical protection component designed for use in demanding power distribution, control and power-electronics applications. Manufactured by Mersen, a recognised specialist in circuit protection, the T300581 is intended to help protect electrical equipment against potentially damaging fault currents.
Industrial fuses provide dependable, maintenance-free circuit interruption by disconnecting a circuit when current exceeds the fuse element's designed operating limits. This helps reduce the risk of damage to cables, semiconductor devices, control equipment and other valuable electrical components.
The Mersen T300581 is suitable for equipment maintenance, repair and replacement requirements where this exact manufacturer reference has been specified. Before installation, the fuse's electrical ratings, physical dimensions, operating class and terminal configuration should be checked against the equipment documentation or the markings on the original component.
Electrical faults can expose industrial equipment to excessive current, heat and mechanical stress. A correctly selected fuse responds by opening the circuit, helping prevent further fault energy from reaching downstream components.
Correct fuse selection is essential for safe and reliable operation. The replacement fuse should match the required voltage, current, interrupting capacity, utilisation category, dimensions and connection type. Installation should be completed by a suitably qualified electrical professional.
| Item number | T300581 |
|---|---|
| Catalogue No | A070UD30TTI400 |
| Description | Square Body High-Speed Fuse Protistor® Size 30 aR 690VAC IEC 700VAC UL 400A With Striker Flush ends UNC threads |
| EAN/UPC Code | 3605340330618 |
| Rated voltage AC UL | 700 V |
| Rated voltage AC IEC | 690 V |
| Ampere Rating | 400 A |
| RoHS Compliant | Yes |
| AC or DC | AC |
| Speed/Characteristic | aR |
| Fuse Size | 30 |
| Mounting | Bolted |
| Clearing I2t At Rated Voltage | 130 kA²s |
| Melting I2t | 23 kA²s |
| 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 | 40 mm |
| Product Length | 50.6 mm |
| Product Height | 48 mm |
| Sell Pack Quantity | 3 EA |
| Sell Pack Weight | 0.765 kg |
| Sell Pack Width | 80 mm |
| Sell Pack Length | 135 mm |
| Sell Pack Height | 55 mm |
| Product group | Semiconductor Protection Fuses |
| Body/Insulating Material | Ceramic |
| Product Weight | 0.255 kg |
| Power Dissipation at Rated Current Value | 60 W |
| HS Code | 85361090 |
| Country of Manufacture | France |
The Mersen T300581 is used for electrical circuit protection in compatible industrial equipment, helping interrupt excessive current during an overload or short-circuit fault.
It may be used as a replacement where the equipment manufacturer specifies Mersen T300581. All electrical ratings, dimensions and terminal details should be verified before installation.
No substitution should be made without confirming compatibility. The replacement must meet the equipment manufacturer's requirements for current, voltage, fuse class, breaking capacity and physical format.
No. A fuse is a non-resettable protection device and must be replaced after its fusible element has operated.
Installation should be carried out by a suitably qualified electrical professional after the equipment has been safely isolated and the replacement specification has been verified.
Mersen circuit protection products are used by electrical engineers, maintenance professionals and equipment manufacturers to support safe and dependable operation across industrial power and automation systems.
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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...