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Mercury 5 x 20mm F2.5A Quick Blow Fuse - 250V

£149
The RRP is the manufacturer's recommended retail price of the item.
Limited Stock
We are an Independent UK Company
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Description

The Mercury F2.5A is a 5 x 20mm glass quick blow fuse rated at 2.5A and 250V, designed to protect sensitive electronics from overcurrent faults. The fast-acting design interrupts the circuit within milliseconds of detecting an overcurrent condition, preventing damage to components downstream of the fuse.

Quick blow fuses are used in audio equipment, power supplies, test instruments, lighting controllers and other devices where immediate circuit protection is needed rather than the delayed response of slow-blow types. The 5 x 20mm format is a standard cartridge fuse size that fits fuse holders in most consumer and professional electronics manufactured in the last 30 years.

The glass body allows visual inspection of the fuse element after a blow event, confirming whether the fuse has operated. The fuse complies with IEC international safety standards and carries a 250V voltage rating, making it suitable for UK 230V mains-fed equipment with headroom for voltage transients.

Frequently Asked

What's the difference between quick blow and slow blow fuses?

Quick blow fuses interrupt the circuit immediately when current exceeds the rated value, typically within milliseconds. Slow blow fuses tolerate brief current surges (such as motor start-up or capacitor charging) and only blow if the overcurrent condition persists for several seconds. Quick blow types suit sensitive electronics; slow blow types suit inductive loads.

Can I use a 2.5A fuse in a circuit rated for 3A?

No. The fuse rating must match or slightly exceed the maximum normal operating current of the circuit. Using a 2.5A fuse in a 3A circuit will cause nuisance blowing under normal load. Always replace fuses with the same rating specified by the equipment manufacturer.

How do I know if the fuse has blown?

The glass body allows you to see the internal fuse element. If the metal wire inside the glass tube is broken or discoloured, the fuse has blown and must be replaced.

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 F2.5A is a 5 x 20mm glass quick blow fuse rated at 2.5A and 250V, designed to protect sensitive electronics from overcurrent faults. The fast-acting design interrupts the circuit within milliseconds of detecting an overcurrent condition, preventing damage to components downstream of the fuse.

    Quick blow fuses are used in audio equipment, power supplies, test instruments, lighting controllers and other devices where immediate circuit protection is needed rather than the delayed response of slow-blow types. The 5 x 20mm format is a standard cartridge fuse size that fits fuse holders in most consumer and professional electronics manufactured in the last 30 years.

    The glass body allows visual inspection of the fuse element after a blow event, confirming whether the fuse has operated. The fuse complies with IEC international safety standards and carries a 250V voltage rating, making it suitable for UK 230V mains-fed equipment with headroom for voltage transients.

    Frequently Asked

    What's the difference between quick blow and slow blow fuses?

    Quick blow fuses interrupt the circuit immediately when current exceeds the rated value, typically within milliseconds. Slow blow fuses tolerate brief current surges (such as motor start-up or capacitor charging) and only blow if the overcurrent condition persists for several seconds. Quick blow types suit sensitive electronics; slow blow types suit inductive loads.

    Can I use a 2.5A fuse in a circuit rated for 3A?

    No. The fuse rating must match or slightly exceed the maximum normal operating current of the circuit. Using a 2.5A fuse in a 3A circuit will cause nuisance blowing under normal load. Always replace fuses with the same rating specified by the equipment manufacturer.

    How do I know if the fuse has blown?

    The glass body allows you to see the internal fuse element. If the metal wire inside the glass tube is broken or discoloured, the fuse has blown and must be replaced.

    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.