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Mercury 5 x 20mm F315mA Quick Blow Fuses - 250V Glass

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

The Mercury F315mA is a 5 x 20mm glass quick blow fuse rated at 315mA and 250V, designed to protect low-current circuits in audio equipment, lighting controllers, battery chargers and other sensitive electronics. The quick blow characteristic means the fuse responds within milliseconds of an overcurrent event, cutting power before downstream components can be damaged.

Quick blow fuses differ from time-delay types by opening the circuit immediately on overload, making them suited to equipment with stable current draw where any sudden spike indicates a fault. The 315mA rating sits between the more common 250mA and 500mA values, giving precise protection for circuits that draw between 200-300mA under normal operation but require fast isolation if that draw exceeds 315mA.

The 5 x 20mm glass cartridge format is an IEC standard used across European and international equipment, fitting into standard panel-mount and PCB-mount fuseholders. The glass body allows visual inspection of the internal filament — a blown fuse shows a broken wire and often carbon deposits on the inside of the glass. The nickel-plated end caps provide corrosion-resistant contact and are compatible with both clip-type and screw-terminal fuseholders.

Frequently Asked

What does 'quick blow' mean?

Quick blow (also called fast-acting or fast-blow) means the fuse opens the circuit within milliseconds of the current exceeding its rated value. This is the opposite of time-delay or slow-blow fuses, which tolerate brief surges without blowing.

What equipment uses 315mA fuses?

315mA fuses are commonly found in audio mixers, small amplifiers, LED controllers, battery chargers, and other low-power electronics where the operating current is stable but protection is needed against short circuits or component failure.

Are these sold individually or in packs?

Please check the product options or contact us to confirm the pack quantity for this listing.

Can I use a higher-rated fuse if I don't have the exact value?

No. Using a higher-rated fuse (e.g. 500mA instead of 315mA) removes the protection the equipment was designed with and may allow damage to occur before the fuse blows. Always replace with the same rating.

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 F315mA is a 5 x 20mm glass quick blow fuse rated at 315mA and 250V, designed to protect low-current circuits in audio equipment, lighting controllers, battery chargers and other sensitive electronics. The quick blow characteristic means the fuse responds within milliseconds of an overcurrent event, cutting power before downstream components can be damaged.

    Quick blow fuses differ from time-delay types by opening the circuit immediately on overload, making them suited to equipment with stable current draw where any sudden spike indicates a fault. The 315mA rating sits between the more common 250mA and 500mA values, giving precise protection for circuits that draw between 200-300mA under normal operation but require fast isolation if that draw exceeds 315mA.

    The 5 x 20mm glass cartridge format is an IEC standard used across European and international equipment, fitting into standard panel-mount and PCB-mount fuseholders. The glass body allows visual inspection of the internal filament — a blown fuse shows a broken wire and often carbon deposits on the inside of the glass. The nickel-plated end caps provide corrosion-resistant contact and are compatible with both clip-type and screw-terminal fuseholders.

    Frequently Asked

    What does 'quick blow' mean?

    Quick blow (also called fast-acting or fast-blow) means the fuse opens the circuit within milliseconds of the current exceeding its rated value. This is the opposite of time-delay or slow-blow fuses, which tolerate brief surges without blowing.

    What equipment uses 315mA fuses?

    315mA fuses are commonly found in audio mixers, small amplifiers, LED controllers, battery chargers, and other low-power electronics where the operating current is stable but protection is needed against short circuits or component failure.

    Are these sold individually or in packs?

    Please check the product options or contact us to confirm the pack quantity for this listing.

    Can I use a higher-rated fuse if I don't have the exact value?

    No. Using a higher-rated fuse (e.g. 500mA instead of 315mA) removes the protection the equipment was designed with and may allow damage to occur before the fuse blows. Always replace with the same rating.

    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.