Converting a battery pointer to wallwart pointer?

[CnJsdad]

I built a spirograph and the batteries on my pointer doesn't last long. Is there a way I can hack my pointer and supply power from a wallwart?
Thanks!

 

[Nocturnal]

what battery does the pointer take?

 

[CnJsdad]

2 AAA's

 

[Nocturnal]

USA DC 3V 1A Switching Power Supply adapter 100-240 AC | eBay

positive to case
negative to spring

its a green pointer right?

 

[jimdt7]

I think 1A is too much. :thinking:

Jim

 

[Nocturnal]

I think 1A is too much. :thinking:

Jim

1A is the maximum draw you can take from the wallwart. the laser's driver will limit the current

 

[jimdt7]

^^^^^ Yes but that may overheat the componements on the driver !

Jim

 

[Nocturnal]

hmm, no. I'm 99% sure that's not the case. It will only overheat with:
1: Heaps current going through- wont happen because of current limiting, and
2: Extra voltage above what is required for driver- wont happen because the wallwart is supplying 3v, exactly what the driver was designed for.

I owe you a massive apology if I'm wrong, but I'm 99% sure it wont over heat components any more than 2xAAA's

 

[jimdt7]

We will see !

Jim

 

[bobhaha]

Nocturnal is correct.

The wallwart is a constant voltage device. It will output 3V no matter what it's connect to. The driver in this case will see 3V at 0-1A the driver will then use the constant voltage source to regulate a constant current to the diode.

Constant current and constant voltage devices are binary opposites. Constant current will give out a constant amperage while the voltage draw can fluctuate within the devices rated range.

 

[CnJsdad]

USA DC 3V 1A Switching Power Supply adapter 100-240 AC | eBay

positive to case
negative to spring

its a green pointer right?

Yes it is a green pointer.

 

[CnJsdad]

I plan on getting a regulated wallwart so the voltage is stable.

 

[Nocturnal]

yep that's the one you need.

USA DC 3V 1A Switching Power Supply adapter 100-240 AC | eBay

Thanks bobhaha for clearing that up

 

[CnJsdad]

yep that's the one you need.

USA DC 3V 1A Switching Power Supply adapter 100-240 AC | eBay

Thanks bobhaha for clearing that up

Thanks for the link! I ordered 3 for the 3 projects I have going.:worthy:

 

[Bionic-Badger]

Jim, if you have no clue about what you're talking about, don't open your fat yap.

All voltage supplies, which include batteries, are ideally supposed to have infinite current supply capability. A wall wart supplying only 1A max is just a limitation of the hardware, and ideally would also provide infinite current.

If your driver is relying on the battery or wall wart to limit current, you have a pretty shitty driver.

 

[jimdt7]

^^^^^^^^^
I said that because some cheap chinese laser dont even use a driver, just a resistor
or simply nothing.
I also said that from my experience when i plugged my cheap green to a power supply,
at 3V and 1A and the switch board started to glow because the resistor was flaming hot.

Jim