No, poor punctuation apparently.
Isn't it apparent from "Ib ≤ In ≤ Iz" and 433; and also as Britain is the only place that uses them (additional fuses).
No, poor punctuation apparently.
Isn't it apparent from "Ib ≤ In ≤ Iz" and 433; and also as Britain is the only place that uses them (additional fuses).
It's Ib ≤ In ≤ Iz
Not Ib ≤ In << Iz
It means that you may use a 13A fuse.
You may.
How do the billions of people in the rest of the world get by when they are unable to avoid this bad thing?
Fascinating, but I'd still like to know why the OP can't fit the replacement fuse.
Because he failed to notice, when removing the old one, where it goes?
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but not identical.
When you say the external fuse is to protect only the cable and the internal fuse is to protect the equipment ask yourself one question.
How far does the "external" cable extend into the equipment before reaching the internal fuse that is protecting the equipment.
Does it meet the fuse immediately at entry point as in this power inlet with fuse built in
or does the cable wend it way from entry point and into the innards of the equipment before meeting the fuse that protects the equipment. A short from Live to Neutral on the cable between entry point and the internal fuse will be "protected" only by the fuse in the 13 plug or FCU and not by the internal fuse. A dead short should result in the fuse blowing quickly but a low resistance short circuit fault could generate a lot of heat inside the appliance before a 13 amp external fuse blows.
Not if the bit of cable inside between the entry point and the fuse is correctly rated at 16 amps in its surroundings.
The heat may not be generated in the cable but in other material(s) inside the appliance that is (are) linking Live to Neutral. Think about faults that might happen and not what should happen in normal use and condition.
Either zero distance, or until the point where the csa reduces below the level which can be protected by the circuit OPD.
Any faults which occur inside the equipment are entirely the responsibility of the manufacturer.
And those materials are entirely the choice of the manufacturer, and therefore he is entirely responsible if they are inadequate.
Think about electric showers.
Open one up and you will find it choc-full of PCBs, electronic components and wires way too small to be protected by a 50A device.
Do you know of any makers who say there must be 2 supplies - a 50A one for the heating, and a 3A one for the control gubbins?
If they can do it, why can't everyone?
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Now I^_^m confused...
So am I, not sure which shower BAS has been looking at.
The last few electric showers I have dealt with have had nothing more than a flow switch, maybe a solenoid to control the flow, a power switch to switch power to one or two elements as required and some safety thermostats to cut power in the case of water and / or heating can becoming too hot.
No doubt some of the better showers with superior functions will have PCB's but then a low current fuse will be incorporated ( may be disguised as a fusible resistor ) to protect the PCB from over current damage.
Q.E.D., then?
No, they were too small to contain a suitable protective device. Basic physics.
Why?
And?
In my case the Redring Selectronic.
Any one with membrane type pushbutton controls.
Any one with a digital readout.
Any one with remote controls.
Any one with an on-off switch clearly not clunky enough to be a mechanical 50A rated jobby.
Any one with thermostatic regulation rather than a crude over-temperature cutout.
Precisely.
So if they can do it, why can't everybody?
No, they were deliberately made too small to contain a suitable protective device. Basic crap design,
Because it clearly is not necessary to omit internal protection and have to rely on the circuit device, so it is clearly a deliberate decision to do so, so it is clearly a deliberate decision to make a flaky and inadequate product.
That should never be acceptable.
And therefore accessories are not outside the scope of BS 7671.
What about products that are designed to fulfill a task that requires them to be a certain size or they cannot be used?
As above, sometimes it is necessary. It does not result in a flaky or inadequate product when used in accordance with the manufacturer's instructions.
I think you need to read it again.
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