Adding an LED to your driver? :thinking:

[Pi R Squared]

Ok well it depends on the switch, usually you would have just a single pole switch on either the negative or positive side of the circuit between the battery and driver, this could be the tailcap switch, in that case if you put the resistor and LED in parallel with the switch then yes you would create the equivalent of the switch being on except with resistance that may prevent lasing but cause more power drain. A tailcap switch complicates this idea, you need to connect the resistor and LED across the output of the battery, or the input to the driver but before the switch. This won't be easy with most designs. It would be easy if you just wanted an LED on when the laser is turned on, but if you want it on whenever there are batteries in the laser then it has to be wired different like I just explained.

Alan

 

[dubious speculation]

I can see where you're coming from now. My initial idea is incorrect since you can't exactly put an led and resistor in parallel with a switch since it in effect bypasses the switch completely. Like you said I'd need to put the led and resistor in parallel with the + and - output of the batteries before the switch. I'm a complete idiot since I only just realised that the switch is only on the negative output of the battery as opposed to being in parallel with the power source

In order to accomplish this I'd need to connect the led and resistor in parallel to the negative(-) input of the spring and the positive(+) input on the driver (or wherever there is a solid positive ground). Since this is where the batteries voltage is being carried prior to the switch and the driver. Is that correct? And would that work effectively?

 

[Pi R Squared]

Yes you got it right.

Alan

 

[autonomousperson]

Thanks Pi R,

Regarding the slight drain on the batteries that's kinda the point :beer:

In effect it will remind the end user to remove the batteries once operation has finished. With these kind of obscenely powerful leadlights that can turn on extremely easily it is imperative that they do not remain 'loaded' when not in use.

However I don't understand why this won't work well, what exactly do you mean by 'partly closing the switch'? Also, isn't in parallel with the batteries kinda the same thing as in parallel with the switch? since the led and resistor are placed in parallel with the switches input there is no current going through the switch before it is depressed, thus the switch won't be 'partly on', which is physically impossible I'm pretty sure. I dunno, am I missing something? :undecided:

I did something similar with a chain of smd leds. They were in parallel with the switch. You just need a reristor to limit the current to prevent the laser driver from activating. I can post a link to a tutorial I made on BLF for a xhp70 build.

 

[Pi R Squared]

I did something similar with a chain of smd leds. They were in parallel with the switch. You just need a reristor to limit the current to prevent the laser driver from activating. I can post a link to a tutorial I made on BLF for a xhp70 build.

Most of our lasers are a simple DC series circuit, the current flows from the negative of the battery to the driver to the laser diode out the laser diode to the driver and to the positive of the battery. I don't know how to explain it any simpler, if you put the LED and resister in parallel with the switch then it will require current to flow through the driver and the laser diode to light the LED. This is a very bad design if you just want to show when the battery is in, it would also require a higher voltage to work because of the voltage drop across the driver and diode, so the battery can't be drained much before the LED wouldn't light.

Alan