Standard delivery
£8 ex VAT · free over £200UK parcel delivery is £8 ex VAT, or free on orders over £200 ex VAT.
Heavier items may be charged at a weight-based or pallet rate, shown at checkout.
MERSEN FUSE 250V 5ST 1A 5.20 MI5ST25V1
Mersen R090543 1 A 250 V AC 5 x 20 mm time-lag IEC miniature fuse designed for reliable overcurrent protection in industrial and electronic equipment.
Why Choose the Mersen R090543 Time-Lag Miniature Fuse?
The Mersen R090543 is a high-quality 5 x 20 mm time-lag (T) miniature fuse designed to provide reliable overcurrent protection for industrial electrical equipment and electronic circuits. Manufactured by Mersen, this fuse is part of the proven 5ST IEC Miniature Fuse Series, offering dependable protection for applications where temporary inrush currents occur during normal operation.
Its time-delay characteristic enables the fuse to withstand short-duration current surges generated by motors, transformers and power supplies while still providing effective protection against sustained overloads and short circuits. This helps reduce nuisance fuse operation and improves equipment availability.
Rated at 1 A and 250 V AC, the Mersen R090543 is ideal for industrial control panels, automation systems, instrumentation and OEM machinery requiring reliable IEC-compliant circuit protection.
Key Advantages
- Time-lag design withstands temporary inrush currents.
- 1 A current rating for reliable circuit protection.
- 250 V AC voltage rating for industrial applications.
- Compact 5 x 20 mm IEC miniature fuse.
- Reduces nuisance operation during equipment start-up.
- Manufactured by trusted electrical protection specialist Mersen.
Key Features
- Mersen 5ST IEC Miniature Fuse Series.
- Model: R090543.
- 1 A rated current.
- 250 V AC rated voltage.
- Time-lag (slow-blow) operating characteristic.
- 5 x 20 mm IEC fuse format.
- RoHS compliant.
- Suitable for industrial and commercial electrical equipment.
Reliable Protection for Electrical Equipment
Time-lag miniature fuses are designed to tolerate the brief inrush currents commonly generated when motors, transformers and power supplies are energised. This allows normal equipment operation while still providing dependable protection against sustained overloads and fault currents.
The Mersen R090543 is widely used by panel builders, OEM manufacturers and maintenance engineers requiring dependable protection for industrial control systems and electrical equipment.
Typical Applications
- Industrial control panels.
- Motor control circuits.
- Power supplies.
- Instrumentation equipment.
- Automation systems.
- OEM machinery.
- Control transformers.
- General industrial electrical equipment.
Technical Specifications
Tick the specs you need, then view products that match.
| Current | 1 A | |
|---|---|---|
| Voltage | 250 V | |
| Device Type | Fuse link | |
| Fuse Type | Miniature | |
| Fuse Size | 5x20 mm | |
| Fuse Class | Time delay | |
| Manufacturer | Mersen | |
| Series | 5ST IEC Miniature Fuses | |
| Model | R090543 | |
| Catalogue number | MI5ST25V1 | |
| Product type | Time-lag miniature fuse | |
| Fuse size | 5 x 20 mm | |
| Rated current | 1 A | |
| Rated voltage | 250 V AC | |
| Operating characteristic | Time-lag (T) | |
| Breaking capacity | 35 A | |
| Application | Overcurrent protection | |
| RoHS compliant | Yes |
Frequently Asked Questions
What is the Mersen R090543 used for?
The Mersen R090543 protects industrial electrical and electronic equipment from overloads and short circuits while tolerating temporary inrush currents.
What is the current rating of this fuse?
This miniature fuse has a rated current of 1 A.
Is this a slow-blow fuse?
Yes. The R090543 is a time-lag (T) miniature fuse designed to withstand short-duration current surges during equipment start-up.
What voltage is this fuse designed for?
The fuse is rated for operation on circuits up to 250 V AC.
Where is this fuse commonly installed?
It is commonly installed in industrial control panels, automation equipment, instrumentation, power supplies and OEM machinery requiring IEC miniature fuse protection.
Trusted by Electrical Professionals Worldwide
Mersen miniature fuses are trusted worldwide by panel builders, machine manufacturers and industrial maintenance engineers for delivering dependable, standards-compliant circuit protection across demanding applications.
