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31278 Wohner holder for cylindrical fuses, for semiconductor fuses
Wöhner 31278 AMBUS Panel single-pole DIN rail-mounted semiconductor fuse holder for 14 × 51 mm cylindrical fuse links, rated at 50 A and 690 V AC under IEC specifications.
£17.93
Why Choose the Wöhner 31278 Semiconductor Fuse Holder?
The Wöhner 31278 is a robust single-pole DIN rail-mounted fuse holder for 14 × 51 mm cylindrical fuse links. Designed for semiconductor fuse applications, it provides a secure and compact mounting solution for protecting power electronic equipment in industrial control panels, machinery and electrical distribution systems.
Rated at 50 A and 690 V AC under IEC conditions, the Wöhner 31278 supports high-speed aR, gR and gRL semiconductor fuse links as well as compatible gG and aM fuse links within the manufacturer’s specified power-dissipation limits. Its large conductor clamping range and integrated label holder help simplify panel assembly, wiring and circuit identification.
The holder is suitable for standard mounting-rail installation and features touch-safe IP20 protection. With approvals including IEC, UL, CSA and CCC, plus AC and DC ratings under UL, the Wöhner 31278 is an adaptable choice for industrial applications requiring dependable cylindrical fuse protection.
Key Advantages
- Designed for 14 × 51 mm cylindrical semiconductor fuse links.
- Single-pole configuration for compact circuit protection.
- 50 A rated current and 690 V AC IEC rating.
- Suitable for aR, gR and gRL semiconductor fuse applications.
- Large 1.5 to 35 mm² conductor clamping range.
- Integrated label holder for clear circuit identification.
- DIN rail mounting for quick panel installation.
- IP20 protection and halogen-free construction.
Key Features
- Manufacturer: Wöhner.
- Part number: 31278.
- Part of the AMBUS Panel range.
- Suitable for 14 × 51 mm IEC cylindrical fuse links.
- 1-pole design.
- Rated for mounting-rail installation.
- Cage-clamp terminals with PZ2 screw drive.
- Integrated holder for circuit labels.
- Suitable for field wiring under UL requirements.
- Not suitable for aluminium conductors.
Dependable Protection for Power Electronics
Semiconductor fuse links are designed to interrupt damaging fault currents rapidly, helping protect sensitive components such as rectifiers, inverters, thyristors and variable-speed drives. The Wöhner 31278 provides the secure mechanical and electrical interface needed to install compatible 14 × 51 mm high-speed fuse links within an industrial panel.
Its wide conductor range supports flexible panel wiring, while the integrated label holder improves circuit identification during installation and maintenance. The compact 27 mm width also helps conserve valuable DIN rail space.
For aR, gR and gRL fuse links with power dissipation up to 6.5 W, Wöhner specifies that conductors of at least 25 mm² must be connected. The holder must only be used with copper conductors, as it is not suitable for aluminium cables.
Typical Applications
- Variable-speed drives and frequency converters.
- Industrial rectifiers and inverters.
- Power semiconductor protection.
- Industrial automation systems.
- OEM machinery and production equipment.
- Electrical control panels.
- UPS and power-conversion equipment.
- Industrial power distribution assemblies.
Technical Specifications
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| Conductor Size | 1.5–35 mm² | |
|---|---|---|
| Device Type | Busbar holder / support | |
| Current | 50 A | |
| Manufacturer | Wöhner | |
| Product range | AMBUS Panel | |
| Model | 31278 | |
| Full part number | 31278000 | |
| Product type | Semiconductor cylindrical fuse holder | |
| Fuse-link size | 14 × 51 mm | |
| Fuse-link standard | IEC / HD 60269-2 | |
| Configuration | 1P | |
| Rated current IEC | 50 A | |
| Rated voltage IEC | 690 V AC | |
| Rated insulation voltage | 800 V AC / DC | |
| Rated impulse withstand voltage | 6 kV | |
| Rated current UL | 50 A | |
| Rated voltage UL | 600 V AC / DC | |
| Rated frequency UL | 50 / 60 Hz | |
| UL short-circuit current rating | 100 kA | |
| Conditional short-circuit rating | 80 kA at 690 V with 25 A fuse | |
| Approved fuse operating class | gG | |
| Suitable semiconductor fuse classes | aR, gR and gRL | |
| Permitted fuse-link power dissipation | 6.5 W | |
| Typical device power dissipation at 80% load | 0.6 W | |
| Device power dissipation at full load | 0.9 W | |
| Dimensions (W × H × D) | 27 × 90 × 69 mm | |
| Approximate weight | 97 g | |
| Mounting | DIN rail | |
| Degree of protection | IP20 | |
| Front degree of protection | IP20 | |
| Terminal type | Cage-clamp connection | |
| Conductor cross-section | 1.5 to 35 mm² | |
| UL conductor range | AWG 14 to AWG 2 | |
| Wire stripping length | 14 mm | |
| Terminal tightening torque | 2.5 to 3.0 Nm | |
| Minimum operating temperature | -40°C | |
| Suitable for aluminium conductors | No | |
| Halogen free | Yes | |
| Pack size | 6 | |
| EAN | 4021267312787 | |
| ECLASS 14.0 | 27142190 | |
| ETIM classification | EC002705 | |
| Standards | IEC 60947-1:2020, IEC 60947-3:2020 and UL 4248-1 | |
| Approvals | IEC CB, UL, CSA and CCC | |
| Type number | AES14x51 |
Frequently Asked Questions
What fuse size does the Wöhner 31278 accept?
The Wöhner 31278 accepts 14 × 51 mm cylindrical fuse links manufactured in accordance with IEC or HD 60269-2.
What is the rated current of the Wöhner 31278?
The fuse holder has a rated current of 50 A under both IEC and UL specifications.
What voltage is the Wöhner 31278 rated for?
It is rated at 690 V AC under IEC specifications and 600 V AC or DC under UL specifications.
Is the Wöhner 31278 suitable for semiconductor fuses?
Yes. It is designed for semiconductor fuse applications and supports compatible aR, gR and gRL fuse links, subject to the manufacturer’s power-dissipation and conductor-size requirements.
What conductor sizes can be connected?
The cage-clamp terminals accept copper conductors from 1.5 to 35 mm². Aluminium conductors must not be used.
Can the Wöhner 31278 be mounted on a DIN rail?
Yes. The holder is designed for standard DIN rail installation in electrical control panels and distribution assemblies.
What are the dimensions of the Wöhner 31278?
The fuse holder measures approximately 27 × 90 × 69 mm.
Trusted by Industrial Professionals Worldwide
Wöhner AMBUS Panel fuse holders are trusted by panel builders, OEM manufacturers and industrial engineers for secure installation, dependable circuit protection and compliance with recognised international electrical standards.
