Is This True (1 Viewer)

May 7, 2016
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CC7906F0-A6CC-4EED-BA63-DFCD387ADBC3.png

Is the bit in this article that says because the isolator is rated at 300A at 48V it is good for 1,200A at 12V true? Sounds a bit dodgy to me, I would not expect a 240V 13A fuse to carry 260A at 12V, I would expect it to go pop.
 
Jan 19, 2014
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Think they rate them at less amps as the voltage rises because the contacts can weld together when switching high wattage. This is why some switches have a non switching max current of more.

Fuses don't have to switch on and off so their current rating is constant.
 
OP
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May 7, 2016
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Somewhat worrying when the technical advice in a popular motorhome magazine contains misleading information.
 
Mar 10, 2016
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Its nonsense, the switch is rated at a maximum of 300A UP TO a maximum of 48vDC. It is still rated at 300A at 12vDC. All sorts of factors go into switch design and you cannot simply do an ohm's law multiplication. In fact Durite do a 550A version as well.
 
OP
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May 7, 2016
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Its nonsense, the switch is rated at a maximum of 300A UP TO a maximum of 48vDC. It is still rated at 300A at 12vDC. All sorts of factors go into switch design and you cannot simply do an ohm's law multiplication. In fact Durite do a 550A version as well.
That is what I thought, thank you for confirming it. Having divided the voltage by 4 he has wrongly multiplied the current by 4, which I find very worrying in a technical article.
 
Mar 10, 2016
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Three years and counting, 30 years a tent tower.
That is what I thought, thank you for confirming it. Having divided the voltage by 4 he has wrongly multiplied the current by 4, which I find very worrying in a technical article.
Yes, me too! Odd because most Tech magazine articles are vetted as they could make themselves liable giving incorrect information. The voltage classification gives what level of withstand the insulation of the switch is capable of, the current rating gives the ability of the metal conductors, contacts etc to carry the rated current. In this use neither voltage or current can be related using Ohm's law.

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Lenny HB

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Oct 18, 2007
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I think there was an artical in C&CC club on batteries they were saying AGM were the best choice for off grid use. I think it must have been April 1st ?
Problem is a lot of people believe what magazines publish. The only one I know that gives honest opinions and not afraid to slate manufacturers is Promobil, shame it's not available in English.
 

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