Nartel® BS1362 Fuse Cartridge 13 amp for UK plugs (Pack of 10)

Product Information

BS 1362 also specifies the fusing current as 1.9 times the rated current (I f = 1.9 I n). If the current exceeds the fusing current, the fuse must blow within 30 minutes. So a 13A fuse must blow within 30 minutes when carrying a current that exceeds 24.7A. The fusein a plugis a deliberate weak link in a circuit which will 'blow' if an electrical appliance or extension lead draws too much current due to either an overload or a fault. The outcome of all this is to not worry about these minor domestic overload problems, as one can see from the normal use one sees, they rarely cause any trouble at all. Loose connections are the cause of problems, not overload of cables.

Surprisingly the fuse does contain the sand filling required, most counterfeit fuses do not have any filling. The sand is required to control the breaking operation of the fuse. Without this filling material, the air within the fuse expands as the fuse wire melts and arcs, causing the fuse to explode, as demonstrated in our previous article on fake fuses. The fuses have the ASTA approval symbol and appear to be branded 'CF' and marked AF63. (A BS1362 fuse must have the manufacturer's name or identifying mark.) They also have a number printed on them: SS157. i) The rated current or current setting of the protective device (In) is not less than the design current (Ib) of the The wire inside a fuse heats up when a current passes through it. The more current that passes, the hotter the wire will get. If the current is high enough, the wire will melt and cut the power to the appliance. The rated current of the fuse, in this case 13A, is the current that it can safely pass whilst maintaining a low enough temperature not to overheat the plug. BS 1362, the British Standard for the fuses used in plugs, specifies a maximum power dissipation of one watt when carrying the rated current. In the spirit of learning from my betters I will lay myself open to ridicule! I'm faintly terrified at having my life changed though! ?Look at these curves and look at the ‘all blow’ right hand curve, vs the left hand ‘never blow’ limit for 13 and 3A fuses. Reference 4F3A a 1.5mm2 single phase AC flexible cable has a tabulated current carrying capacity of 16amps. 16x0.763 = 12.208 amps which is obviously less than the 13 amp rating of the fuse. Leading on to… 433.20/202 where an allowance is made for the fusing factor of a 3036 fuse. If the fusing factor of a 1362 is at 1.9 it is fairly comparable so surely we must apply a comparable derating factor? This is where the wheels come off my bus if the answer is more than just… It doesnt protect against overload. I find it quite common to see 13A 1362 fuses inline on 32A cooker circuits protecting 1.5mm2 flexes to ovens. Is this deemed acceptable even though the oven isn't strictly speaking a fixed load (fan motor etc.)?

Breaking the fuse open confirms that these fuses are counterfeit. There is no sand filling. The quartz sand inside a genuine BS1362 is designed to control the rupture of the fuse wire within the ceramic body. If you are purchasing fuses online, we recommend only using a reputable supplier such as RS Components or Farnell. Both of these companies are able to provide data sheets and compliance documentation for the products they sell. Identifying counterfeit electrical equipment is becoming an important part of the inspection process and is something that we cover in our courses. Counterfeit BS1362 Fuse Testing The rated current may be any value not exceeding 13A. For use in plugs, the preferred rated currents are 3 A and 13 A." Fusing factor for the BS1362 is 1.9 compared to 1.45 for a type B. Therefore tabulated cable rating needs to be: I appreciate that there will be manufacturers tolerances both for the device and the cable (which could go both ways) and that there is undoubtedly going to be some headroom in the cable. I've seen a plumber leave a 9.0kW electric boiler on a bit of 1.5 flex before and yeah (prior to me fixing it) it was pretty hot after a few hours but it hadn't melted! Is the answer just that we're only talking about an extra amp in the example and whilst it may get a bit hotter than would be ideal this isn't the end of the world or are we into the realms of trying to work out how much heat is being dissipated during the fault by the flex as it is going to be happening over quite a prolonged timeframe?ii) the rated current or current setting of the protective device (In) does not exceed the lowest of the currentcarrying The car draws 250 to 300A to spin the starter. How long can I crank the engine while my son and the nervous alarm man hold the 2.5mm onto the 2 batteries without burning either of them ? Where I'm getting turned around. The current (I2) causing effective operation of the protective device does not exceed 1.45 times the lowest of the current carrying capacities (Iz) of the conductors of the circuit. Now I did not quite use Chris's figure of 3 mins at 20 A, but if I had it would have scaled to 3mins/100 at 200A, or about 2 seconds for a 40 degree rise. I had a more optimistic figure, allowing a bit for the PVC, and as I did not have the regs with me, so used a pidooma figure from memory.

These domestic plug fuses are ideal for protecting the flexible lead between theplugand appliances to prevent fires due to large currents. The 3A and 5A fuses also have larger than normal dimples on the caps. A requirement of BS1362 is that "The end surfaces shall be substantially flat". There is no evidence of a trapped fuse wire, although the large dimples indicate that these could also be fake. Breaking capacity is the level of current that the fuse can safely handle without exploding or breaking. The breaking capacity of your fuse should be greater than the fault current of your electronic circuit. It may not be immediately apparent, but a 13A rated fuse is not designed to actually blow at 13A. In fact, a 13A fuse will allow a current of 20A to pass indefinitely without blowing. If we look at the graph in Fig 1, it shows the operating characteristics for both 3A and 13A BS 1362 fuses. The grey shaded area is the point where the fuse is designed to operate. So for example, a 13A fuse will blow within 0.01 - 0.3 seconds for a fault current of 100A; shown in red on the graph. For a current of 20A, shown in blue on the graph, a 13A fuse will not blow! Why does a 13A rated fuse not blow at 13A? The rated current or current setting of the protective device (In) does not exceed the lowest of the current carrying (Iz) of any of the conductors of the circuit, andIn reality only AWE or CERN will install a cable in vacuum like that, and of course any real cable will heat quite a lot more slowly. So there we are, a 2.5 sqmm cable loaded at 20 A will take over 45 minutes to get up to 70 deg C from 20 deg C enclosed in conduit in an insulated wall. Any smaller loading or less lagging and it will never get there because the heat generated in the conductors will always be less than the available heat loss.

I'd never have dared to do anything like that - 2.5mm is for 16 amps innit ?” well maybe under some condition, not sure what alarm chaps get taught about installation methods and de-rating..It is a setting where a circuit experiences a current that is higher than the normal operating current. This confusion (at least, in my mind!) seems to arise at least partially because 433.1.202 has been included completely unnecessarily, tempting one to think that BS3036 fuses are the only devices that require 'special attention/thought'. In reality, it is but just one example of a device with a 'fusing factor' which is not 1.45 (hence I 2 is not 1.45I n) , such that they could also have included (as another 'special case'), say, your BS1362 with a fusing factor of 1.9 (or whatever) ... or, better, not have this reg at all, and just let people work out I 2 for themselves.. HBC stands for high breaking current and refers to the maximum current that the fuse can handle without breaking. It is also known as HRC (High Rupturing Capacity).