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Mercury 5 x 20mm F20A Quick Blow Fuses - Pack of 5

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

The Mercury F20A is a 5 x 20mm glass cartridge quick blow fuse rated at 20A and 250V, supplied in packs of five. Quick blow (fast-acting) fuses are designed to interrupt the circuit within milliseconds of an overcurrent event, providing protection for sensitive electronics, amplifiers, power supplies and AV equipment where rapid fault response is needed.

Designed for installation in fused IEC mains inlets, fuse holders, amplifier rear panels and power distribution units, the 5 x 20mm format is a standard size across audio, AV, lighting control and electrical equipment. The glass body allows visual inspection of the internal wire element, making it easy to identify a blown fuse without needing a multimeter.

The 20A rating handles equipment drawing up to 20 amps on a 250V supply before the fuse blows. The quick blow response time means the fuse interrupts the circuit faster than slow-blow or time-delay fuses, which are used in equipment that has high inrush currents on startup. The fuses meet IEC standards for safety and performance, ensuring consistent operation across different installations.

Frequently Asked

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

Quick blow fuses interrupt the circuit within milliseconds of an overcurrent event. Slow blow (time-delay) fuses tolerate brief current surges on startup before blowing, making them suitable for motors and transformers. Quick blow fuses are used where immediate protection is needed for sensitive electronics.

What equipment uses 5 x 20mm fuses?

The 5 x 20mm format is common in audio amplifiers, DJ mixers, lighting controllers, power supplies, IEC mains inlets and distribution units. Check your equipment's manual or the existing fuse to confirm the size and rating before ordering.

Can I replace a blown fuse with a higher-rated one?

No. Always replace a fuse with the same rating and type (quick blow vs slow blow) specified by the equipment manufacturer. Using a higher-rated fuse removes the protection the original fuse was designed to provide, risking damage to the equipment or fire hazard.

How do I know if the fuse has blown?

The glass body allows you to see the internal wire element. A blown fuse will have a broken wire visible inside the glass tube, often with black discolouration on the glass itself.

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 F20A is a 5 x 20mm glass cartridge quick blow fuse rated at 20A and 250V, supplied in packs of five. Quick blow (fast-acting) fuses are designed to interrupt the circuit within milliseconds of an overcurrent event, providing protection for sensitive electronics, amplifiers, power supplies and AV equipment where rapid fault response is needed.

    Designed for installation in fused IEC mains inlets, fuse holders, amplifier rear panels and power distribution units, the 5 x 20mm format is a standard size across audio, AV, lighting control and electrical equipment. The glass body allows visual inspection of the internal wire element, making it easy to identify a blown fuse without needing a multimeter.

    The 20A rating handles equipment drawing up to 20 amps on a 250V supply before the fuse blows. The quick blow response time means the fuse interrupts the circuit faster than slow-blow or time-delay fuses, which are used in equipment that has high inrush currents on startup. The fuses meet IEC standards for safety and performance, ensuring consistent operation across different installations.

    Frequently Asked

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

    Quick blow fuses interrupt the circuit within milliseconds of an overcurrent event. Slow blow (time-delay) fuses tolerate brief current surges on startup before blowing, making them suitable for motors and transformers. Quick blow fuses are used where immediate protection is needed for sensitive electronics.

    What equipment uses 5 x 20mm fuses?

    The 5 x 20mm format is common in audio amplifiers, DJ mixers, lighting controllers, power supplies, IEC mains inlets and distribution units. Check your equipment's manual or the existing fuse to confirm the size and rating before ordering.

    Can I replace a blown fuse with a higher-rated one?

    No. Always replace a fuse with the same rating and type (quick blow vs slow blow) specified by the equipment manufacturer. Using a higher-rated fuse removes the protection the original fuse was designed to provide, risking damage to the equipment or fire hazard.

    How do I know if the fuse has blown?

    The glass body allows you to see the internal wire element. A blown fuse will have a broken wire visible inside the glass tube, often with black discolouration on the glass itself.

    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.