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Mercury 5 x 20mm T100mA Slow Blow Fuse - 250V

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

The Mercury T100mA is a slow blow fuse in a 5 x 20mm glass tube with metal end caps, rated at 250V and 100mA (0.1A). The time-delay element inside the glass allows brief surge currents during equipment start-up or motor inrush without blowing, while still protecting against sustained overcurrent or short circuits at 100mA and above.

Designed for low-current electronic equipment, audio amplifiers, power supplies and precision instrumentation where brief surges need to be tolerated but sustained fault current must be interrupted. The 5 x 20mm tube fits standard fuse clips and panel-mount holders common in European and UK electrical equipment. The glass tube allows visual inspection of the fuse element without removal.

The T-rated (time-delay) element distinguishes this from an F-rated (fast-blow) fuse of the same physical size. Under sustained 100mA overcurrent the fuse will blow within seconds to minutes depending on the exact overload factor, but transient surges up to several hundred milliamps lasting a few milliseconds will not cause nuisance blowing. The metal end caps provide a secure grip in spring-loaded fuse clips.

Frequently Asked

What does T100mA mean?

The T indicates a time-delay (slow blow) fuse, and 100mA is the rated current. The fuse will tolerate brief surge currents above 100mA during equipment start-up, but will blow under sustained overcurrent to protect the circuit.

What voltage is it rated for?

250V. This is the maximum voltage the fuse can safely interrupt when it blows. Using the fuse in circuits above 250V can result in dangerous arcing when the fuse element melts.

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

Slow blow (T-rated) fuses have a time-delay element that tolerates brief surge currents without blowing, making them suitable for circuits with inductive loads or equipment that draws higher current at start-up. Fast blow (F-rated) fuses interrupt overcurrent immediately and are used where surge tolerance is not required.

Can I use this in place of a higher-rated fuse?

No. Always replace a fuse with one of the same rating and type. Using a lower-rated fuse (like a 100mA in place of a 500mA) will cause nuisance blowing. Using a higher-rated fuse in a 100mA circuit removes the protection the original fuse was providing.

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 T100mA is a slow blow fuse in a 5 x 20mm glass tube with metal end caps, rated at 250V and 100mA (0.1A). The time-delay element inside the glass allows brief surge currents during equipment start-up or motor inrush without blowing, while still protecting against sustained overcurrent or short circuits at 100mA and above.

    Designed for low-current electronic equipment, audio amplifiers, power supplies and precision instrumentation where brief surges need to be tolerated but sustained fault current must be interrupted. The 5 x 20mm tube fits standard fuse clips and panel-mount holders common in European and UK electrical equipment. The glass tube allows visual inspection of the fuse element without removal.

    The T-rated (time-delay) element distinguishes this from an F-rated (fast-blow) fuse of the same physical size. Under sustained 100mA overcurrent the fuse will blow within seconds to minutes depending on the exact overload factor, but transient surges up to several hundred milliamps lasting a few milliseconds will not cause nuisance blowing. The metal end caps provide a secure grip in spring-loaded fuse clips.

    Frequently Asked

    What does T100mA mean?

    The T indicates a time-delay (slow blow) fuse, and 100mA is the rated current. The fuse will tolerate brief surge currents above 100mA during equipment start-up, but will blow under sustained overcurrent to protect the circuit.

    What voltage is it rated for?

    250V. This is the maximum voltage the fuse can safely interrupt when it blows. Using the fuse in circuits above 250V can result in dangerous arcing when the fuse element melts.

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

    Slow blow (T-rated) fuses have a time-delay element that tolerates brief surge currents without blowing, making them suitable for circuits with inductive loads or equipment that draws higher current at start-up. Fast blow (F-rated) fuses interrupt overcurrent immediately and are used where surge tolerance is not required.

    Can I use this in place of a higher-rated fuse?

    No. Always replace a fuse with one of the same rating and type. Using a lower-rated fuse (like a 100mA in place of a 500mA) will cause nuisance blowing. Using a higher-rated fuse in a 100mA circuit removes the protection the original fuse was providing.

    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.