Hello.
Old mobility battery chargers have a fuse to protect the current input.
New chargers don't have that input fuse.
Advantages and disadvantages.
Opinions about it.
Burgerman wrote:The AC side does not need a fuse in the UK as theres one in every AC plug. But even if not visible there may be one internally.
ex-Gooserider wrote:Worth noting that if something blows on the mains side with a modern switching type charger, the charger is almost certainly toast... The DC output side has the protection on it that limits how much can be drawn by the AC side. So short the output and the DC protection will limit the drain on the entire unit.... Only way to get excess draw on the AC side is for something in the switching circuitry to die. (nothing like that "magic smoke" aroma...)
Since we don't have schematics, a non-replaceable fuse isn't a problem as the rest of the unit is ready to be binned anyway.
ex-Gooserider
Burgerman wrote:The AC side does not need a fuse in the UK as theres one in every AC plug. But even if not visible there may be one internally.
martin007 wrote:ex-Gooserider wrote:Worth noting that if something blows on the mains side with a modern switching type charger, the charger is almost certainly toast... The DC output side has the protection on it that limits how much can be drawn by the AC side. So short the output and the DC protection will limit the drain on the entire unit.... Only way to get excess draw on the AC side is for something in the switching circuitry to die. (nothing like that "magic smoke" aroma...)
Since we don't have schematics, a non-replaceable fuse isn't a problem as the rest of the unit is ready to be binned anyway.
ex-Gooserider
Do you have any kind of extra protection for PSUs?
ex-Gooserider wrote:martin007 wrote:ex-Gooserider wrote:Worth noting that if something blows on the mains side with a modern switching type charger, the charger is almost certainly toast... The DC output side has the protection on it that limits how much can be drawn by the AC side. So short the output and the DC protection will limit the drain on the entire unit.... Only way to get excess draw on the AC side is for something in the switching circuitry to die. (nothing like that "magic smoke" aroma...)
Since we don't have schematics, a non-replaceable fuse isn't a problem as the rest of the unit is ready to be binned anyway.
ex-Gooserider
Do you have any kind of extra protection for PSUs?
Same thing applies to modern switching style PSU's, wall warts, etc... Remember that the typical 'mobility brick' charger is basically just a PSU with some added circuitry to give (supposedly, pretending they actually did it right) it the appropriate charge curve output when connected to a battery....
So the same basic thing applies, typically they will have some sort of protection on the DC output, either a fuse, or some sort of current limiting shutoff circuitry. Optional is a diode to prevent harm if hooking it up backwards... (often depends on the use case) This protects the AC side if everything is working right. The AC side will typically have either a component or circuit board trace very close to the input that will fail open if something in the supply itself fails... (generally it is considered bad to rely on popping the fuse / breaker on the mains, since the manufacturer has no knowledge / control over that.)
ex-Gooserider
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