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Mercury 5 x 20mm F250mA Quick Blow Fuse - 250V IEC Approved

£149
The RRP is the manufacturer's recommended retail price of the item.
Limited Stock
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Description

The Mercury F250mA is a 5 x 20mm quick blow glass fuse rated at 250mA and 250V, designed to provide immediate circuit isolation when current exceeds the rated threshold. The quick blow characteristic means the fuse responds within milliseconds of an overload, protecting sensitive electronics from sustained overcurrent damage.

Used in audio equipment, power supplies, lighting control circuits, and other fine electronics where rapid fault isolation is critical, the fuse fits standard 5 x 20mm fuse holders common in European and UK equipment. The glass tube construction allows visual inspection of the internal filament to confirm whether the fuse has blown without needing test equipment.

The 250V rating suits both 230V mains applications and lower-voltage DC circuits in amplifiers, mixers and similar equipment. IEC approval confirms the fuse meets international safety standards for construction and performance. The fuse is a consumable component and should be replaced only with an identical rating — using a higher-rated fuse can compromise circuit protection and invalidate equipment warranties.

Frequently Asked

What does 'quick blow' mean?

A quick blow fuse responds immediately to overcurrent, typically breaking the circuit within milliseconds. This contrasts with slow blow or time-delay fuses that tolerate brief current surges without blowing, which are used where inrush current is normal (motors, transformers).

Can I replace a 250mA fuse with a higher-rated one?

No. Fuses are sized to protect the circuit and components downstream. Installing a higher-rated fuse (e.g. 500mA or 1A) allows more current to flow before the fuse breaks, which can damage components or create a fire risk.

What equipment uses 5 x 20mm fuses?

The 5 x 20mm profile is standard in audio mixers, DJ equipment, lighting controllers, power supplies and other fine electronics. Check the equipment's fuse holder or manual to confirm the correct size and rating before ordering.

Is the fuse reusable?

No. Once a fuse blows, the internal filament is permanently broken and the fuse must be replaced. Attempting to bypass or repair a blown fuse removes the circuit protection and creates a safety hazard.

Shipping & Returns

Delivery UK delivery is £14.99, and delivery is free on all orders of £99 or more, in the UK and internationally.

Returns If you change your mind, you have 14 days from delivery to tell us, and a further 14 days to send the goods back. Return postage for a change-of-mind return is paid by you. Change-of-mind returns are subject to an inspection and handling deduction. See our full returns policy.

To arrange a return, call us on 020 8149 5199 or use our contact page.

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    Description

    The Mercury F250mA is a 5 x 20mm quick blow glass fuse rated at 250mA and 250V, designed to provide immediate circuit isolation when current exceeds the rated threshold. The quick blow characteristic means the fuse responds within milliseconds of an overload, protecting sensitive electronics from sustained overcurrent damage.

    Used in audio equipment, power supplies, lighting control circuits, and other fine electronics where rapid fault isolation is critical, the fuse fits standard 5 x 20mm fuse holders common in European and UK equipment. The glass tube construction allows visual inspection of the internal filament to confirm whether the fuse has blown without needing test equipment.

    The 250V rating suits both 230V mains applications and lower-voltage DC circuits in amplifiers, mixers and similar equipment. IEC approval confirms the fuse meets international safety standards for construction and performance. The fuse is a consumable component and should be replaced only with an identical rating — using a higher-rated fuse can compromise circuit protection and invalidate equipment warranties.

    Frequently Asked

    What does 'quick blow' mean?

    A quick blow fuse responds immediately to overcurrent, typically breaking the circuit within milliseconds. This contrasts with slow blow or time-delay fuses that tolerate brief current surges without blowing, which are used where inrush current is normal (motors, transformers).

    Can I replace a 250mA fuse with a higher-rated one?

    No. Fuses are sized to protect the circuit and components downstream. Installing a higher-rated fuse (e.g. 500mA or 1A) allows more current to flow before the fuse breaks, which can damage components or create a fire risk.

    What equipment uses 5 x 20mm fuses?

    The 5 x 20mm profile is standard in audio mixers, DJ equipment, lighting controllers, power supplies and other fine electronics. Check the equipment's fuse holder or manual to confirm the correct size and rating before ordering.

    Is the fuse reusable?

    No. Once a fuse blows, the internal filament is permanently broken and the fuse must be replaced. Attempting to bypass or repair a blown fuse removes the circuit protection and creates a safety hazard.

    Shipping & Returns

    Delivery UK delivery is £14.99, and delivery is free on all orders of £99 or more, in the UK and internationally.

    Returns If you change your mind, you have 14 days from delivery to tell us, and a further 14 days to send the goods back. Return postage for a change-of-mind return is paid by you. Change-of-mind returns are subject to an inspection and handling deduction. See our full returns policy.

    To arrange a return, call us on 020 8149 5199 or use our contact page.