difference between quick and ultra rapid blow fuse ? - Page 1
Forum section: electronics / beginners

author: nour
author_rank: Frequent Contributor
timestamp: February 19, 2016, 10:10:18 pm
content: what is the difference between quick and ultra rapid blow fuse ?which is better for 220v plug?

author: wraper
author_rank: Unknown
timestamp: February 19, 2016, 10:13:52 pm
content: Quote from: nour on February 19, 2016, 10:10:18 pmThere is no better. There is a right thing to use depending on the load it protects.

author: nour
author_rank: Frequent Contributor
timestamp: February 19, 2016, 10:16:51 pm
content: Quote from: wraper on February 19, 2016, 10:13:52 pmok it's a standard 13 amps 220v (250v) bs1363 plug , that was the second half of the question

author: nour
author_rank: Frequent Contributor
timestamp: February 19, 2016, 10:29:06 pm
content: to be Clearer, the plug is for generic use

author: mmagin
author_rank: Frequent Contributor
timestamp: February 19, 2016, 11:14:31 pm
content: Aren't there fuses which are specifically safety approved for use in bs1363 plugs?

author: ade
author_rank: Unknown
timestamp: February 19, 2016, 11:23:39 pm
content: Just use a standard fuse conforming to BS 1362, which has its own speed requirements. The fuse is there to protect the cable, not to protect the load or appliance.Appliances / devices which are very sensitive to shorts tend to have one or more additional fuses in them already. Plus there is another fuse in the fuse box.

author: Gyro
author_rank: Super Contributor
timestamp: February 20, 2016, 10:03:52 am
content: You've said nothing to indicate that the ultra rapid fuse has a high enough fault current interrupt rating. Use a standard BS 1362 conforming fuse as ade says.

author: wraper
author_rank: Unknown
timestamp: February 20, 2016, 10:08:48 am
content: Quote from: nour on February 19, 2016, 10:16:51 pmThere is a special fuse type for this. Usual fuses won't fit there because of the different dimensions.

author: wraper
author_rank: Unknown
timestamp: February 20, 2016, 10:11:26 am
content: Quote

author: SeanB
author_rank: Super Contributor
timestamp: February 20, 2016, 11:05:51 am
content: Quick blow and ultra quick blow fuses are meant to be installed inside the final equipment. The plug fuse must be the BS1362 approved type, to protect the cable against burning in case of a short in the appliance.The quick blow fuse is typically used to protect resistive loads and is not recommended for use with switching power supplies, electric motors and such as to get the inrush rating the fuse rating is way above what will protect. They are only there for things like impedance protected transformers and motors, those small ones where the short circuit current in the secondary or the stalled rotor current is only a small amount over standard full load current, where the fuse provides protection. Also used on the secondary to protect against overcurrent, but not where inrush current is too high.Ultra quick blow is used to protect semiconductor devices, where it has the possibility of protecting a rugged power semiconductor, likely a power transistor or power diode, against an overcurrent condition, or to clear the overcurrent in case of a short across the output. There it might blow faster than the power device, though in many cases it will not be faster than the fusing silicon.