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USB-C charging law in the EU.
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nctnico:

--- Quote from: Siwastaja on November 15, 2023, 03:59:55 pm ---If you don't believe me, observe it yourself: look how easily an electric drill rated to 500W or more stalls and compare it to even a cheap battery powered drill.

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I'm not sure this is a fair comparison as the power versus torque graphs for the motors may be different depending on the intended use. In the end the power rating says very little over what amount of torque a drill can develop at the chuck. You need to take the gear ratio into account. An electric drill designed to primarily drill holes will have a different gear ratio because it needs to rotate as higher speeds (like 3000 RPM) compared to a drill primarily designed to drive screws in (which rotates at ballpark 450 RPM). For example: the Makita corded screw driver 'drill' I have is made to provide torque at low speeds. As a consequence it is stronger (=more torque) compared to its battery powered counterparts.
AVGresponding:

--- Quote from: Siwastaja on November 15, 2023, 04:20:34 pm ---
--- Quote from: PapierzToaletowy on November 15, 2023, 09:46:29 am ---Using mains powered tools is probably unlikely in US given how they still cling onto 120V and low-amperage sockets.

At least in EU it's possible to draw 2-3kW without melting the plug, socket or wiring. To standardize on 230V and CEE 7/7 was a really smart decision.


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Here's a fun fact to you: in the UK, the country of EVEN BETTER plugs than ours, there is a complete separate ecosystem of 120-volt power tools for really serious professional use at construction sites*, so clearly 120V isn't a problem. Let that fact sink in; OTOH, with a political anti-USA agenda, I'm quite sure you are not interested about such trivial things as facts.

*) the idea is to use a 240-V input, 120V output transformer with earthed center tap. This way, potential between either legs to true earth/PE/plumbing is 60VACrms, which is deemed pretty safe. One can see how great this idea was before the era of RCDs; UK electrical system is full of great ideas implemented well.

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Nitpicking I know, but it's 110VAC with a CTE.

Bizarrely enough, for the higher power stuff (big core drills, concrete saws etc) we jump straight from 110VAC to 400VAC 3-ph...
wraper:

--- Quote from: Siwastaja on November 15, 2023, 03:59:55 pm ---If you don't believe me, observe it yourself: look how easily an electric drill rated to 500W or more stalls and compare it to even a cheap battery powered drill. The difference in power consumption isn't 10x I admit that but 4x difference is well possible. If one is 60% efficient then the other can be 15-20%. You can also see how much more air flow the cooling fans on these cheap-ass corded tools produce compared to battery variants.

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Cordless drills usually are more like electric screwdrivers that can also drill. So RPM will be like a half of an average mains powered drill that has higher RPM and no torque adjustment, so not suitable for screws. And again, cordless tools, especially cheap usually have brushed motor. BLDC is usually used in better tools. Often basically the same model comes in both variants with some performance advantage in BLDC version.
SiliconWizard:
Yep. And while efficiency per se is not that much different as you pointed out, a brushed motor will by design wear out much faster. When it does, either you feel like renovating the motor by changing the brushes yourself (as long as you can find the parts), or you throw it away as finding the motor itself as a spare part is even less likely. Brushless motors have much, much longer lifetime.
wraper:

--- Quote from: SiliconWizard on November 15, 2023, 10:10:47 pm ---When it does, either you feel like renovating the motor by changing the brushes yourself (as long as you can find the parts), or you throw it away as finding the motor itself as a spare part is even less likely. Brushless motors have much, much longer lifetime.

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If you replace brushes timely, brushed motor can last a very long time. In better tools, brushes usually have a wear protection, they electrically disconnect when become worn out to prevent motor damage. As of DIY use, they'll last forever. The downside of BLDC is that it can accumulate magnetic dust and shavings.
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