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Mercury 5 x 20mm F2A Quick Blow Fuses - 2A 250V Glass

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

The Mercury F2A is a 5 x 20mm quick blow glass fuse rated at 2A and 250V, designed to interrupt current flow within milliseconds of detecting an overcurrent or short circuit. The glass tube body contains a thin wire element visible through the casing, allowing visual inspection of blown fuses without needing a multimeter.

Quick blow fuses are used in circuits where sensitive electronics require immediate protection rather than the delayed response of slow-blow types. Common applications include AV equipment, DJ mixers, amplifiers, low-voltage lighting controllers, and small power supplies where a 2A maximum draw is expected. The 5 x 20mm form factor is a standard size that fits most IEC-compliant fuse holders and clips used in consumer electronics and professional audio gear.

The fuse meets IEC 127 compliance for dimensional consistency and breaking capacity, which means it will physically fit standard holders and reliably interrupt fault currents within the rated voltage range. The glass construction allows for quick fault diagnosis — a broken or blackened element inside the tube indicates the fuse has blown and needs replacement. Each fuse weighs approximately 0.5g and has nickel-plated brass end caps for consistent contact with the fuse holder terminals.

Frequently Asked

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

Quick blow fuses interrupt current within milliseconds when the rated amperage is exceeded, protecting sensitive circuits from brief surges. Slow blow fuses tolerate temporary overcurrent spikes (like motor start-up) and only blow after sustained overload. For low-current electronics and AV equipment, quick blow is typically required.

Can these be used in mains plugs?

No. UK mains plugs require BS 1362 certified fuses (typically 13A cartridge type). These 5 x 20mm fuses are designed for internal circuit protection in equipment, not mains plug use.

How do I know if the fuse has blown?

Inspect the glass tube under light. A blown fuse will have a visibly broken wire element inside, often with blackening or discolouration on the glass from the arc. If the element appears intact but the circuit still doesn't function, test with a multimeter set to continuity mode.

Are these sold individually or in packs?

Check the product listing for pack quantity. Mercury fuses are typically sold in packs of 10 or 20 to provide spares for equipment maintenance.

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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Free delivery on orders over £99, in the UK and worldwide. Easy returns within 14 days, subject to our returns policy. Full manufacturer warranty included.

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    Description

    The Mercury F2A is a 5 x 20mm quick blow glass fuse rated at 2A and 250V, designed to interrupt current flow within milliseconds of detecting an overcurrent or short circuit. The glass tube body contains a thin wire element visible through the casing, allowing visual inspection of blown fuses without needing a multimeter.

    Quick blow fuses are used in circuits where sensitive electronics require immediate protection rather than the delayed response of slow-blow types. Common applications include AV equipment, DJ mixers, amplifiers, low-voltage lighting controllers, and small power supplies where a 2A maximum draw is expected. The 5 x 20mm form factor is a standard size that fits most IEC-compliant fuse holders and clips used in consumer electronics and professional audio gear.

    The fuse meets IEC 127 compliance for dimensional consistency and breaking capacity, which means it will physically fit standard holders and reliably interrupt fault currents within the rated voltage range. The glass construction allows for quick fault diagnosis — a broken or blackened element inside the tube indicates the fuse has blown and needs replacement. Each fuse weighs approximately 0.5g and has nickel-plated brass end caps for consistent contact with the fuse holder terminals.

    Frequently Asked

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

    Quick blow fuses interrupt current within milliseconds when the rated amperage is exceeded, protecting sensitive circuits from brief surges. Slow blow fuses tolerate temporary overcurrent spikes (like motor start-up) and only blow after sustained overload. For low-current electronics and AV equipment, quick blow is typically required.

    Can these be used in mains plugs?

    No. UK mains plugs require BS 1362 certified fuses (typically 13A cartridge type). These 5 x 20mm fuses are designed for internal circuit protection in equipment, not mains plug use.

    How do I know if the fuse has blown?

    Inspect the glass tube under light. A blown fuse will have a visibly broken wire element inside, often with blackening or discolouration on the glass from the arc. If the element appears intact but the circuit still doesn't function, test with a multimeter set to continuity mode.

    Are these sold individually or in packs?

    Check the product listing for pack quantity. Mercury fuses are typically sold in packs of 10 or 20 to provide spares for equipment maintenance.

    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.