Electrical Leakage On The Magnetic Charging Port - Is It Dangerous

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vietnamreviews
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Electrical Leakage On The Magnetic Charging Port - Is It Dangerous

A friend asked me about the leakage on the SKILHUNT H04F RC magnet charging port. I sent a letter to SKILHUNT and they said: H04 RC charging port have short circuit protected function. So you have SKILHUNT H04F RC please rest assured to use. There is one thing you should pay attention not to share SKILHUNT H04F RC and the key to minimize risk as I analyze in the clip.
SKILHUNT H04F RC is my great headlamp. It is very light in weight and customizable for a wide variety of usage scenarios such as high or low beam.
What’s your opinion ?

SammysHP
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Olight has also the full cell voltage on the contacts. Early models had no protection, on newer models the current is limited to a few mA.

Sunnysunsun
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If you’re really curious, try putting some steel or a wire to bridge it (temporarily). Be very care to push it away after a short time so you don’t cause damage? Note: idk if this might damage something

kennybobby
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Good review video. i’m still a little alarmed to see exposed voltage on the port, maybe it needs a magnetic cover made of plastic to prevent a key or other metal from accidentally touching across the electrodes.

i wouldn’t want you to damage your light, but a test of short circuit protection should be made to verify that it works. i’m afraid it may not actually work and would cause damage. The design is not good in that it puts voltage on the exposed port and is a risk of damage or spark.

What is the schematic of the circuit that provides the short circuit protection? How much current can flow before the protection kicks in? These would be important to understand before it can be declared “safe”.

Now i used to think that i was cool,
drivin' around on fossil fuel,
until i saw what i was doin',
was drivin' down the road to ruin. --JT

vietnamreviews
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kennybobby wrote:
Good review video. i’m still a little alarmed to see exposed voltage on the port, maybe it needs a magnetic cover made of plastic to prevent a key or other metal from accidentally touching across the electrodes.

i wouldn’t want you to damage your light, but a test of short circuit protection should be made to verify that it works. i’m afraid it may not actually work and would cause damage. The design is not good in that it puts voltage on the exposed port and is a risk of damage or spark.

What is the schematic of the circuit that provides the short circuit protection? How much current can flow before the protection kicks in? These would be important to understand before it can be declared “safe”.


I agree with you. I am counting on Skilhunt’s statement. But maybe we should still have an independent test
thefreeman
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I tested with a bunch of 0.5Ω resistances, down to 1Ω current rises up to 2.8A (bat=3.9V) and then at 0.5Ω no current anymore, so there is a protection.

Edit : with a real short it does spark, but still no current afterwards.

kennybobby
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thefreeman wrote:
I tested with a bunch of 0.5Ω resistances, down to 1Ω current rises up to 2.8A (bat=3.9V) and then at 0.5Ω no current anymore, so there is a protection.

Edit : with a real short it does spark, but still no current afterwards.

Merci, Thank you for doing the test. What is the power rating of your resistors?

Approx 8W for the 1Ω test, could the last 0.5Ω resistor have let go under 30W load?

Now i used to think that i was cool,
drivin' around on fossil fuel,
until i saw what i was doin',
was drivin' down the road to ruin. --JT

thefreeman
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50W, but like I said in the edit, I shorted the contacts with a wire in the end, no current (measured with current clamp)

kennybobby
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Très bien!

Now i used to think that i was cool,
drivin' around on fossil fuel,
until i saw what i was doin',
was drivin' down the road to ruin. --JT

rdhood
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A deliberate short circuit bench test is better than an accidental short circuit test in your pocket

SammysHP
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thefreeman wrote:
I tested with a bunch of 0.5Ω resistances, down to 1Ω current rises up to 2.8A (bat=3.9V) and then at 0.5Ω no current anymore, so there is a protection.

Edit : with a real short it does spark, but still no current afterwards.


Which means that using this light in a wet environment (for example in rain, when a drop of water bridges the contacts) will drain the battery.