help a noob. its not working right

[hazerb30]

hi guys n gals. Great forum you have here.

Hoping someone can point me in the right direction. I just want 3 CREEs to work in parallel off a 12v battery

12.5v big battery 210ah
3 x Cree XR-E 3.7v

So i did the reading and figured out the resistors required and have 3 globes in parallel. I found a 240VAC to 12VDC transformer and plugged it in (shed will be run off a battery instead though)

Problem is they LEDs are flashing very quickly. Ive never encountered this problem with normal 5mm led's but the crees flash. I thought maybe dodgy power supp so i got another one and it flashes as well but a lot slower. Its definently 12vdc output not ac.

Looking around here everyone is using drivers or pucks or whatever. Is it something to do with PWM ? im lost from here.. I just want a simple solution without having to look for more components ? Can i build something ?

Cheers for any help.


Oh man...... ill still post this but ive just realised i wired the buggers up in parrallel and not series. hahahaha. its getting late here. Doh.. hope they didnt get hammered too bad!!