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Mercury 5 x 20mm T2.5A Slow Blow Fuse - 250V Time-Delay

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

The Mercury T2.5A is a 5 x 20mm slow blow fuse rated for 250V with a time-delay mechanism that allows brief power surges to pass through without blowing, while still protecting against sustained overloads above 2.5A. The glass body houses a single fuse wire visible through the transparent casing, with nickel-plated brass end caps providing contact at each terminal.

Slow blow fuses (also called time-delay or T-rated fuses) are used in small equipment that draws brief high-current loads on startup or during operation, such as motors, transformers, power supplies and audio amplifiers. The T2.5A rating means the fuse can handle short-duration current spikes above 2.5A without interrupting the circuit, but will blow if the overcurrent condition persists for more than a few seconds. This prevents nuisance blowing during normal operation while still providing protection against faults.

The 5 x 20mm format is one of the most common cartridge fuse sizes internationally and fits standard panel-mount fuse holders, inline cable fuse holders and PCB-mount clips used across consumer electronics, audio equipment, lighting control gear and industrial control panels. The fuse conforms to IEC 60127 standards for small fuses, ensuring dimensional and performance compatibility with equipment designed to those specifications.

Frequently Asked

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

A fast blow (F-rated) fuse interrupts the circuit almost immediately when current exceeds its rating. A slow blow (T-rated) fuse like this one tolerates brief overcurrent conditions for a few seconds, allowing motors and transformers to start without blowing the fuse, but still protects against sustained faults.

What voltage is this rated for?

The fuse is rated for 250V maximum. It can be used in circuits operating at lower voltages (e.g. 12V, 24V, 110V, 230V) but must not be used in circuits exceeding 250V.

How many fuses are included?

The product listing shows individual fuses. Check the quantity selector or product description for pack size — Mercury fuses are typically sold in packs of 10 or boxes of 100.

Will this fit my equipment?

If your equipment specifies a 5 x 20mm fuse holder and requires a T2.5A or 2.5A slow blow rating, this fuse will fit. Do not substitute a different current rating or fuse type (e.g. fast blow) unless you are certain the equipment can tolerate the change.

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 T2.5A is a 5 x 20mm slow blow fuse rated for 250V with a time-delay mechanism that allows brief power surges to pass through without blowing, while still protecting against sustained overloads above 2.5A. The glass body houses a single fuse wire visible through the transparent casing, with nickel-plated brass end caps providing contact at each terminal.

    Slow blow fuses (also called time-delay or T-rated fuses) are used in small equipment that draws brief high-current loads on startup or during operation, such as motors, transformers, power supplies and audio amplifiers. The T2.5A rating means the fuse can handle short-duration current spikes above 2.5A without interrupting the circuit, but will blow if the overcurrent condition persists for more than a few seconds. This prevents nuisance blowing during normal operation while still providing protection against faults.

    The 5 x 20mm format is one of the most common cartridge fuse sizes internationally and fits standard panel-mount fuse holders, inline cable fuse holders and PCB-mount clips used across consumer electronics, audio equipment, lighting control gear and industrial control panels. The fuse conforms to IEC 60127 standards for small fuses, ensuring dimensional and performance compatibility with equipment designed to those specifications.

    Frequently Asked

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

    A fast blow (F-rated) fuse interrupts the circuit almost immediately when current exceeds its rating. A slow blow (T-rated) fuse like this one tolerates brief overcurrent conditions for a few seconds, allowing motors and transformers to start without blowing the fuse, but still protects against sustained faults.

    What voltage is this rated for?

    The fuse is rated for 250V maximum. It can be used in circuits operating at lower voltages (e.g. 12V, 24V, 110V, 230V) but must not be used in circuits exceeding 250V.

    How many fuses are included?

    The product listing shows individual fuses. Check the quantity selector or product description for pack size — Mercury fuses are typically sold in packs of 10 or boxes of 100.

    Will this fit my equipment?

    If your equipment specifies a 5 x 20mm fuse holder and requires a T2.5A or 2.5A slow blow rating, this fuse will fit. Do not substitute a different current rating or fuse type (e.g. fast blow) unless you are certain the equipment can tolerate the change.

    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.