Question about resistor in P4

[erahard]

Hi all,

I am about to order the parts for my first saber. I am going to start easy with a simple design following one of the tutorials in this forum. I will use the "Build Your Own Seoul P4 Electronics Kit" for a RED led and 4AAA batteries. My question is:

According to the product info for a RED led I should use a 4.7 Ohm 5W resistor. However I would like to use a Buckpuck 1000mA 4 wire for better efficiency. Is that not possible for my setup?

Sorry if this was asked before but I did bot found the answer on the forums.

Thanks in advance.

[Jedi-Loreen]

The option to add a buck puck to the kit is in the Resistor/Driver drop-down menu on the order page for the P4 kit. ;)

[erahard]

Yes, I saw it. However in that same page as well as in the resistor chart it appears that for a RED P4 I can only use a 4.7 Ohm resistor and not a Buckpuck. This is strange and I was wondering if it was a mistake and I can actually use a Buckpuck.

Thanks.

[equinox13]

the red P4 takes 800mA and there is no 800mA buckpuck. you either have to underdrive it, overdrive it and risk letting the purple smoke out, or use a resistor.

[FenderBender]

Red P4 is rated at 1A max not 800ma. The 800ma rating is a newer change to the Seoul spec sheet, but we haven't had any problems running them at 1A. Overdriving would be anything over that. 1A puck would be fine. A lot of peeps even run them at 1.3-1.4 off of CFs with no problem, they're just voltage sensitive so a proper driver is key.

[equinox13]

Red P4 is rated at 1A max not 800ma.

according to the resistor chart in the store they're 2.5Vf and 800mA. that's what i'm referencing.

as for them being voltage sensitive, that is very good info to have. thanks! ^_^

[erahard]

Thanks for the info. Once I gain some confidence with the workings I may I try to use a 1000mA Buckpuck and see how it goes.