{"product_id":"mercury-t800ma-5-x-20mm-slow-blow-fuse-250v-time-delay","title":"Mercury T800mA 5 x 20mm Slow Blow Fuse - 250V Time Delay","description":"\u003ch5\u003eDescription\u003c\/h5\u003e\n\u003cp\u003eThe Mercury T800mA is a 5 x 20mm glass cartridge fuse with a time-delay (slow blow) element, rated at 800mA breaking capacity and 250V maximum voltage. The time-delay characteristic allows the fuse to tolerate brief current surges during device startup or motor inrush without blowing, while still protecting against sustained overcurrent faults.\u003c\/p\u003e\n\u003cp\u003eDesigned for low-current electronics, audio equipment, control panels and instruments where startup current can temporarily exceed the steady-state operating current, the slow blow design prevents nuisance tripping during normal operation. The 5 x 20mm glass cartridge format fits standard panel-mount and PCB-mount fuse holders, with nickel-plated end caps providing reliable contact and corrosion resistance.\u003c\/p\u003e\n\u003cp\u003eThe fuse is built to IEC standards and carries the appropriate approval markings for use in consumer and industrial equipment sold in the UK and EU. The 800mA rating sits between the more common 500mA and 1A values, making it suitable for equipment drawing steady currents in the 400-600mA range where a 500mA fast-blow fuse would trip prematurely but a 1A fuse would provide insufficient protection.\u003c\/p\u003e\n\u003ch5\u003eFrequently Asked\u003c\/h5\u003e\n\u003cp\u003e\u003cstrong\u003eWhat is a slow blow fuse and when is it needed?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eA slow blow (time-delay) fuse tolerates brief current surges without blowing, typically for 10-100 milliseconds depending on the surge magnitude. This prevents the fuse from tripping during motor startup, transformer inrush, or capacitor charging events in equipment that has a higher startup current than running current.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat equipment uses 800mA fuses?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eCommon applications include audio mixers, guitar amplifiers, control panels, instrumentation, LED drivers and low-power DC supplies. The 800mA rating protects circuits drawing steady currents between 400-600mA where a 500mA fuse is too sensitive and a 1A fuse provides inadequate protection.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eIs this fuse reusable after it blows?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eNo. Glass cartridge fuses are single-use consumables. Once the internal element melts under fault current, the fuse must be replaced. Always replace a blown fuse with the same rating and type — do not substitute a higher-rated or fast-blow fuse.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat is the physical size?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThe fuse measures 5mm diameter by 20mm length, fitting standard 5 x 20mm fuse holders. The glass body is transparent, allowing visual inspection of the internal wire element to confirm whether the fuse has blown.\u003c\/p\u003e","brand":"AVSL","offers":[{"title":"Default Title","offer_id":45313485603083,"sku":"787.009UK","price":1.49,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0729\/8993\/3835\/files\/787009UK_LB1_4ee78881-1279-4d36-b9a2-79b915a21eb9.jpg?v=1715194119","url":"https:\/\/niori.co.uk\/products\/mercury-t800ma-5-x-20mm-slow-blow-fuse-250v-time-delay","provider":"Niori","version":"1.0","type":"link"}