300A 415V porcelain kit kat fuse unit with strip — rewireable carrier and base with bolted end terminals, for main incomers, feeders and LT panels.
- Porcelain fuse unit rated 300A, 415 V — carrier and base.
- With strip: bolted terminals at both ends of the base, with nuts and washers, for cable lugs or busbar links.
- Twin clip contacts in the base take the blade contacts of the carrier.
- Carrier embossed 300A, AC 415/500 V and its maximum fuse wire size.
- Rewireable: refit the carrier with fuse wire of the size specified for the rating.
- Porcelain (ceramic) base and carrier — non-combustible and heat-resistant, the traditional material for fuse units.
- Single pole — use one unit in each phase of a three-phase supply.
A 300A, 415 V porcelain fuse carrier and base for main incomers, feeders and LT panels in commercial buildings, workshops and factories. The base is fixed in the panel and connected through bolted terminals at each end; the carrier holds the fuse wire and plugs into twin clip contacts in the base.
When the current is too high, the fuse wire melts and breaks that phase. Switch off the upstream supply before pulling the carrier, refit fuse wire of the size marked for the rating and push it back. Never fit thicker wire or bridge the carrier — the fuse wire is the protection.
Each unit protects one conductor, so a three-phase feeder needs three units, with the neutral on a link. For a larger incomer choose our 500A heavy unit; for 200A and below, the handle type units.
Where to use it
- Main incoming supply of workshops, commercial buildings and apartment blocks.
- Feeders in LT panels, busbar chambers and industrial switchboards.
- Replacing worn or cracked 300A units in existing panels.
How to install
- Switch off and isolate the upstream supply, and confirm the circuit is dead.
- Fix the base firmly in the panel through its fixing hole.
- Bolt crimped cable lugs or busbar links to the end terminals and tighten the nuts firmly.
- Fit the specified fuse wire in the carrier, tighten its screws and push the carrier fully into the base contacts.
Electrical work should be done by a licensed electrician. Never pull out or push in a fuse carrier on load — switch off the supply first.
Frequently asked questions
- What does "with strip" mean?
- The base is connected through bolted terminals at both ends, with nuts and washers, so heavy cables with crimped lugs, or busbar links, can be bolted on directly.
- How many units do I need for a three-phase supply?
- Three — one in each phase. Each unit is single pole; the neutral goes through a link, never a fuse.
- What fuse wire does a 300A unit take?
- The size marked on the carrier for its rating — follow that marking and the rating chart of the fuse wire you buy. Never use thicker wire or a solid link to stop it blowing.
- Can I pull out the carrier with the supply on?
- No. Switch off the main switch or upstream isolator first — pulling a carrier on load can draw an arc that burns the contacts and the hand holding it.
- 300A or 500A — which one do I need?
- Choose by the maximum current of the feeder and the cable size. For the larger incomers, use the 500A heavy unit; the fuse wire fitted must never exceed what the cable can carry.
- Kit kat fuse or MCB — which should I choose?
- An MCB trips more precisely and resets with a switch — the modern choice for distribution boards. A rewireable fuse is simple and economical and still common in motor, pump and older main-switch boards, but it protects only with the correct fuse wire.
Buy 300A porcelain kit kat fuse units online from Electric Market, Chennai. For panel builders, contractors and bulk orders, contact us for a quote.