PC 1.5 help

[DarthStallion]

hey. you'll need to use a power extender http://www.thecustomsabershop.com/Po...r-20-P652.aspx to bring the voltage of the 3.3v pad to 7.4v then resistor from there. also, be sure your pc 1.5 is set to run foc. i have a couple older pc 1.5's that were flashed to unlock them but they weren't flashed for foc. it think that started with version 1.6.
check your config file. if you see any auxflashXX parameters then you're good to go.
hope that helps.

[patolcott]

ahhh so the power extender is what brings the voltage back up to 7.4 got it i was wondering how that worked. I am sure my PC runs FOC so I need a resistor for a supply voltage of 7.4 with a Vf of 5.2 @ 700 Ma. got it Ill just do the math and grab a resistor tomorrow... or today. thank you

[Forgetful Jedi Knight]

ahhh so the power extender is what brings the voltage back up to 7.4 got it i was wondering how that worked. I am sure my PC runs FOC so I need a resistor for a supply voltage of 7.4 with a Vf of 5.2 @ 700 Ma. got it Ill just do the math and grab a resistor tomorrow... or today. thank you

Something doesn't sound right here. Let's start from the beginning - what EXACTLY are you trying to do with the LED's:

What color(s) are the main LEDs?

What color(s) are the FoC LEDs?

Where did you get the idea that you could run a FoC off the 3.3V pad?

[patolcott]

I have a LEDengin 10w RGGB my GB will be my main blade and my RG will be my flash I never thought I could run it off my 3.3 v pad, I merely thought that the PEX was 3.3 as well since every pad on the pc 1.5 is 3.3

[Forgetful Jedi Knight]

I have a LEDengin 10w RGGB my GB will be my main blade and my RG will be my flash I never thought I could run it off my 3.3 v pad, I merely thought that the PEX was 3.3 as well since every pad on the pc 1.5 is 3.3

It doesn't quite work that way. The PEX allows (more or less) for "direct drive", and the supply voltage depends on the size of the battery pack.

so I need a resistor for a supply voltage of 7.4 with a Vf of 5.2 @ 700 Ma.

You can drive the LEDEngins at 1A (that would make the resistor calculations easier)

IF you are going to the 2 dice FoC, you may want to figure the current (mAh) to be at least 1500mAh (1.5A). Also, you will have a VERY limited run time with the battery pack you have listed.

[patolcott]

Hmm now I am more confused... How do I configure it to run at 1 amp or 1.5 amps? i did not know you could configure that. how long will the run time be? I knew it would be shorter but I don't plan on dueling with it, so a shorter time is OK with me. Thanks for the help

[Forgetful Jedi Knight]

Hmm now I am more confused... How do I configure it to run at 1 amp or 1.5 amps? i did not know you could configure that. how long will the run time be? I knew it would be shorter but I don't plan on dueling with it, so a shorter time is OK with me. Thanks for the help

OK, Let's start from the beginning...

A PEX is basically a direct drive board, that will let you use up to the voltage of the battery pack it's attached to (typically 7.4V) and will allow up to 2A (if you have the newer PEX's) of current to flow through it. Just as you decide what the Vf of the FoC dice you use are (by choosing which dice you use - in the calculations in green) you can choose how much current (up to 2A) to use to feed them (in the calculations in RED).

In your case... you say the 2 Dice you want to use are 5.2V (2.2, 3.0). In actuality, they are more like 2.2 and 3.4. (5.6V)

So, if you want to run them at 1.5A (1500mAh)

The first half of the calculation (to determine the resistance, in Ohms) is:

R = Vf (battery) - (Vf dice) / Current => 7.4 - 5.6 / 1.5 =>1.8 / 1.5 = 1.2 Ohms

The second half of the calculation (to determine wattage)

W = R(from first calculation) * Current^2 => 1.2 * 1.5^2 = 2.7 Watts

So a 1.2 Ohm 3 Watt resistor would be what you need, which Tim seems to have in stock right now.

http://www.thecustomsabershop.com/12...istor-P22.aspx

Your run time with the battery pack you have should max out at about 20 minutes, depending on how high you run the main dice.

Got it now?

[Silver Serpent]

I would highly recommend you try drawing up a wiring diagram for us to look at. There's more than a little bit of confusion going on here.

[Forgetful Jedi Knight]

I would highly recommend you try drawing up a wiring diagram for us to look at. There's more than a little bit of confusion going on here.

I agree with SS here. Though I think I know what you are trying to do now, you should make up a coherent wiring diagram to help you out, and to help us follow along to make sure you stay on track.

[patolcott]

Hey guys I appreciate the help I really think I get it now, I was just missing a piece in the formula. here is my diagram any critiques will be greatly appreciated. * note I already know the LED wiring is not drawn right, I wired it using Fender's tutorial on wiring 10watt LEDengine

Here is the diagram