Hyena
10 GW
OK so this isn't an ebike related question at all, but it is technical 
and I figured those of you with formal electronics training would probably be able to explain this to me.
While playing with a BMS tonight I touched the top of the heatsink and it felt "funny". I don't know how to properly describe the sensation, it just didn't feel right. Obviously I was expecting it feel like a solid lump of metal but it felt hollow with an oddly grippy texture and ever so vaguely like it had some sort of earth leakage going through with a slight tingle, but at the same time not. Somewhat puzzled as to why my senses were playing tricks on me I then rubbed it it really resonated, and gave off that trademark electric hum. And then I realised the sensation I couldn't peg was a type of vibration, like when you run you run your finger around the edge of a glass. When I unplugged the charger it went back to feeling like a lump of metal, with no resonance.
And that's when I thought it must be the switching of the mosfets setting up some sort of resonance through the heatsink block, though I wouldn't have through it would be so pronounced.
Those in the know, is that correct ?
Here's a quick clip of it for those who are interested.
For some reason the sound is only particularly audible on the last heatsink block but it must have just been the camera picking it up better because they all did it.
[youtube]XdjMH85ca7A[/youtube]
and I figured those of you with formal electronics training would probably be able to explain this to me. While playing with a BMS tonight I touched the top of the heatsink and it felt "funny". I don't know how to properly describe the sensation, it just didn't feel right. Obviously I was expecting it feel like a solid lump of metal but it felt hollow with an oddly grippy texture and ever so vaguely like it had some sort of earth leakage going through with a slight tingle, but at the same time not. Somewhat puzzled as to why my senses were playing tricks on me I then rubbed it it really resonated, and gave off that trademark electric hum. And then I realised the sensation I couldn't peg was a type of vibration, like when you run you run your finger around the edge of a glass. When I unplugged the charger it went back to feeling like a lump of metal, with no resonance.
And that's when I thought it must be the switching of the mosfets setting up some sort of resonance through the heatsink block, though I wouldn't have through it would be so pronounced.
Those in the know, is that correct ?
Here's a quick clip of it for those who are interested.
For some reason the sound is only particularly audible on the last heatsink block but it must have just been the camera picking it up better because they all did it.
[youtube]XdjMH85ca7A[/youtube]
