Measuring amps.

[RicModMaker]

It's simply ohms law . With 4.2V you'd get a current of 0.28mA across the resistor, with 8.4V double that. So still negligible.



No need for high wattage resistors, see above. If you have any resistors kicking about work out the current leakage across them with ohms law, if it's acceptably small, then go for it.
You can use any switch you want, the current is so low, as I mentioned . That is one of the biggest advantages of separating the high current side from the switch.

Cool. So just so I'm clear, if I had say 1a tactile switch and slide switch, they'd be more than capable of handling it.

 

[RicModMaker]

Having just looked at a few tactile switches they mostly seem to be 0.05a
Will they work?
Sorry for the noob questions.

 

[Chegs]

Convert the 28ma off doobedoobedo's previous post into Amps (I'm shit at maths) and if your switches can carry the 28ma when rated at 0.05A then bob's your crossdressing aunt

Sent by lazer from just north of the world's largest nuclear dustbin

 

[doobedoobedo]

It's not even 28mA it's 0.28mA = 0.00028A you can use absolutely any rated switch you want. A single strand of copper the width of a hair wouldn't blow.

 

[RicModMaker]

I'm probably being really stupid here but if a switch says its 0.05a isn't that the same as 5ma? Like 0.05metres is 5mm? Someone shoot me, I need burying! ;-)

 

[RicModMaker]

Convert the 28ma off doobedoobedo's previous post into Amps (I'm shit at maths) and if your switches can carry the 28ma when rated at 0.05A then bob's your crossdressing aunt

Sent by lazer from just north of the world's largest nuclear dustbin

It's not even 28mA it's 0.28mA = 0.00028A you can use absolutely any rated switch you want. A single strand of copper the width of a hair wouldn't blow.

Thanks guys. I'll just get some standard 6mm tactile switches.

 

[Chegs]

There you go mate, told you I was shit at maths (plus typing anything on my phone)means I shouldn't actually try and answer questions

Sent by lazer from just north of the world's largest nuclear dustbin

 

[Tubbyengineer]

I'm probably being really stupid here but if a switch says its 0.05a isn't that the same as 5ma? Like 0.05metres is 5mm? Someone shoot me, I need burying! ;-)

0.05a is 50ma. Because there are 1000ma in an amp, anything under an amp will take up 3 spaces after the decimal point - so take the number of say 0.46 amps and use zero's at the nd to make sure you have three numbers after the point and you get the milliamps! 0.46a = 460ma

 

[doobedoobedo]

I'm probably being really stupid here but if a switch says its 0.05a isn't that the same as 5ma? Like 0.05metres is 5mm? Someone shoot me, I need burying! ;-)

No comment on stupidity

0.05m is 5cm milli = thousandths, 1mm = 0.001m, the 0.05A switch is rated for 50mA.

 

[RicModMaker]

No comment on stupidity

0.05m is 5cm milli = thousandths, 1mm = 0.001m, the 0.05A switch is rated for 50mA.

I got confused, which is easily done, when i saw you put: "your switches can carry the 28ma when rated at 0.05A".
Having read it back, I see that I am indeed stupid so please feel free to call me it