How hard can it be to put some kind of electronic limiter on a power tool so if you over-stress it, it doesn't consume enough current to melt the coils?
I assume something like this must be done on electric cars, or instead of stalling the engine, you'd wreck the motor.
How hard can it be to put some kind of electronic limiter on a power tool so if you over-stress it, it doesn't consume enough current to melt the coils?
I assume something like this must be done on electric cars, or instead of stalling the engine, you'd wreck the motor.
The motor is efficiently protected by voltage, current and temperature sensors to prevent overloading. Stop buying junk and start buying Hiltis.
Not neccessary for drills.
I had a Yellow & black device once Worx or somesuch.
I stalled it "sort of"
One's wrist forms a perfect albeit painful mechanical fuse :-(
I suppose right handed people have a slight advantage, but drilling with the left hand on the grip ansures that the drill isn't pulled away, it's pushed into your hand.
AB
I'm not talking about little cordless drills, I mean mains powered tools of around a kilowatt. Even if they're cheap, surely these sensors are a fraction of the price of the whole tool, and you'd get so many less warranty returns.
Do you think you could handle a corded Hilti?
Show me an example. I don't see why anyone (even a woman) couldn't use any power tool.
If you have the time and around £60-00, you could buy an overload and JB to keep it in. I think a standard 3 phase overload will work without a contactor and there is some adjustment for FLC.
It would want two of the channels wiring in series for single phase though.
Thermal fuses are fast acting and cheap, a none rewireable from ebay cost me around a pound for 20, they are good although you would have to dsimantle the tool to see if it could be placed in proximity to the field coils.
AB
Drills aren't so bad. It's more things like saws that can get jammed. And if you don't turn them off within a quarter of a second, the motor dies.
Whatsa coil?
Most motors that are to be used unattended do have thermal overloads in them. I guess hand tool manufacturers assume you will stop before you burn up the tool
I did that with a hedge trimmer once.
But what if you're just slightly overloading it? The motor can't tell you it's working too hard.
Anyway, if the blade jams, even if you react in a third of a second (the average human reaction speed), you've put intense stress on the motor coils. They can draw many times more current when not moving.
P.S. one of my cats looks like she's having an orgasm rolling around in freshly cut concrete dust. That's gonna take her a while to clean out of her fur....
P.S. one of my cats looks like she's having an orgasm rolling around in freshly cut concrete dust. That's gonna take her a while to clean out of her fur....
The only observation I made was the trimmer stopped running. Of course I had a proper 3A fuse in the plug, not the 13A standard everyone seems to use. And no I don't have any form of circuit breaker, earth leakage or otherwise.
Dullest knife in the drawer thinks all power tools are the same - no need to spend a few more quid on "quality" - it's all marketing BS.
He's a cheapscate scotsman who needs something to cry about so only buys junk.
The point is even on cheap power tools, the cost of a bit of electronics would be nothing compared with the whole tool.
And expensive tools like Bosch also don't have limiters.
Most line operated small motors are "impedence protected" - spec says nothing over 150c after running locked rotor for 15 days straight. Impossible to burn those motors out.
Most hand tools have a duty cycle. Excede the duty cycle at your peril. The good ones protect themselves. The cheaper ones let out all the magic smoke.
North american stuff doesn't have fused plugs. We fuse the feed circuit.
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