*SOLVED* CFX and Pixel Blade Wiring - hot wires, battery, and chip

[nunya]

I think I have buttered my toast - please check.

I wired my CFX according to the wiring diagrams and user manual.  I had it all installed and functions were working great.  I built the pixel blade and went to test - that is when problems started.
The blade illuminated as white on all pre-packaged fonts and "tried" to changes colors after entering "spectrum" mode because the LEDs did some odd changes (some went out then came back and the entire blade color seemed to change to a yellow then orange).
I felt the heat coming from the hilt and heard the card state it had reached the predefined temperature threshold.
After disassembling the hilt, I replicated the issue and noticed two wires are getting hot - PCB L- and PCB LR+ (where L is left when looking at the hilt side PCB top where the pins stick out and negative is two contacts left of data line)
I did the measurements as defined in the handbook and got numbers close to the defined values with one having 2V more.
I placed the multimeter contacts on the L- and L+/R+ of the hilt side PCB and activated the saber.  The measured voltage was equal to the battery voltage (7.9V).
I am beginning to suspect the wiring for the blade or something with the LED strip is the cause.  Since it is all glued down, I am hoping to get some guidance on how to confirm before I proceed disassembling further.
The numbers above/below the official ones are my measurements.




*picture is too small - numbers from top left to right (7.76V; 7.9V [matches battery]; 3.15)
*numbers on bottom, left to right (5.01-5.04V; 8.82V; 1.6V; 3.29V; 3.29V)

I am using two 3.7v 14500 800mAh Li-ion rechargeable batteries with resistor installed on PCB.

I also checked for continuity on the hilt side PCB and got some results which I do not understand.
Black contact on center circle (data) and Red contact on outer circle gives 862
Black contact on center circle (data) and Red contact on middle circle (negative) gives 687
Black contact on middle (negative) circle and Red contact on outer circle (positive) gives 469
Black contact on middle (negative) circle and Red contact on center circle (data) gives 1 (no circuit)

[K-2SO]

For starters, that battery solution is no where near enough to power a Neopixel strip for more than few seconds.

Next question would be what gauge wire are you using?

[nunya]

Thanks for the reply!

For starters, that battery solution is no where near enough to power a Neopixel strip for more than few seconds.

The blade will stay lit until I turn it off.  Is the combined 7.4V causing the heating?  I see recommended is 18650 3000mAH - I supposed will be at 3.7V? 

Next question would be what gauge wire are you using?

24 AWG

[scott]

CFX is 3.7V!

[nunya]

CFX is 3.7V!

Thanks! I sure would like to see this clearly stated in the handbook.

[K-2SO]

Thanks for the reply!

For starters, that battery solution is no where near enough to power a Neopixel strip for more than few seconds.

The blade will stay lit until I turn it off.  Is the combined 7.4V causing the heating?  I see recommended is 18650 3000mAH - I supposed will be at 3.7V? 

Next question would be what gauge wire are you using?

24 AWG

Partially. I’m  a tad surprised that the Neopixels are lighting up (though I’m guessing they aren’t very bright), because the output amperage needed to light it up properly is easily 8A and the battery solution you have doesn’t output that nearly that much. The 18650 15A output battery are the standards for Neopixels.

Also, 24 gauge is pushing it for the Neopixel wires. Usually you need 22 gauge to get the maximum brightness.

[jbkuma]

Directly from the manual:

The board is mostly targeted to the use of a single li-ion cell using direct drive (external resistors)
for HB leds sabers or ledstrip sabers. The board is however compatible with 2 cell and a current
regulator for HB leds, or a +5V buck regulator to the ledstrip.
Ni-MH battery packs are simply not recommended due to their larger energy storage/volume ratio
and poor current draw. The board accepts a maximum voltage of 10V.

That being said pixel strips neither require nor do they function best at 5v. They can tolerate 5v, but 3.8v-4v is really the sweet spot, anything more than that just generates more heat.

[jbkuma]

Partially. I’m  a tad surprised that the Neopixels are lighting up (though I’m guessing they aren’t very bright), because the output amperage needed to light it up properly is easily 8A and the battery solution you have doesn’t output that nearly that much. The 18650 15A output battery are the standards for Neopixels.

A single color blade will more typically top off around 3A, but obviously a wimpy 14500 isn't even ideal for that.

[nunya]

Partially. I’m  a tad surprised that the Neopixels are lighting up (though I’m guessing they aren’t very bright), because the output amperage needed to light it up properly is easily 8A and the battery solution you have doesn’t output that nearly that much. The 18650 15A output battery are the standards for Neopixels.

Also, 24 gauge is pushing it for the Neopixel wires. Usually you need 22 gauge to get the maximum brightness.

True enough - it is not very bright.  I have purchased the proper battery and will see what happens.

Once again I find the handbook to be lacking, confusing, or contradictory. 
It states on page 14 "we suggest...24-28 AWG wire, not bigger" - bigger is 29+ or 23- ??? I would have thought bigger meaning 22,20,etc.

Later, on page 29, "AWG 22 or 24". I have to go with practical applications which brings me to this forum.  Thanks for the answers.

[nunya]

Directly from the manual:

The board is mostly targeted to the use of a single li-ion cell using direct drive (external resistors)
for HB leds sabers or ledstrip sabers. The board is however compatible with 2 cell and a current
regulator for HB leds, or a +5V buck regulator to the ledstrip.
Ni-MH battery packs are simply not recommended due to their larger energy storage/volume ratio
and poor current draw. The board accepts a maximum voltage of 10V.

That being said pixel strips neither require nor do they function best at 5v. They can tolerate 5v, but 3.8v-4v is really the sweet spot, anything more than that just generates more heat.

great to know about the voltage!  thanks! I came across the 5V limit in the manual or from other readings but thought the card would manage that...
I saw that paragraph in the manual but I am not using Ni-MH and mine says 9V max. It also does not clearly state "use 3.7V noob"! 

[K-2SO]

Directly from the manual:

The board is mostly targeted to the use of a single li-ion cell using direct drive (external resistors)
for HB leds sabers or ledstrip sabers. The board is however compatible with 2 cell and a current
regulator for HB leds, or a +5V buck regulator to the ledstrip.
Ni-MH battery packs are simply not recommended due to their larger energy storage/volume ratio
and poor current draw. The board accepts a maximum voltage of 10V.

That being said pixel strips neither require nor do they function best at 5v. They can tolerate 5v, but 3.8v-4v is really the sweet spot, anything more than that just generates more heat.

great to know about the voltage!  thanks! I came across the 5V limit in the manual or from other readings but thought the card would manage that...
I saw that paragraph in the manual but I am not using Ni-MH and mine says 9V max. It also does not clearly state "use 3.7V noob"! 

Allow me to help you:

“Use 3.7V/15A noob!”

Seriously, the proper battery solution will help you immensely.

[nunya]

thanks to you all for the replies.  I will come back after a while with an update.

[nunya]

Thanks for the reply!

For starters, that battery solution is no where near enough to power a Neopixel strip for more than few seconds.

The blade will stay lit until I turn it off.  Is the combined 7.4V causing the heating?  I see recommended is 18650 3000mAH - I supposed will be at 3.7V? 

Next question would be what gauge wire are you using?

24 AWG

Partially. I’m  a tad surprised that the Neopixels are lighting up (though I’m guessing they aren’t very bright), because the output amperage needed to light it up properly is easily 8A and the battery solution you have doesn’t output that nearly that much. The 18650 15A output battery are the standards for Neopixels.

Also, 24 gauge is pushing it for the Neopixel wires. Usually you need 22 gauge to get the maximum brightness.

Minor adjustment on the gauge of wire: I am using 24 throughout the hilt but the wires from Blade side PCB to LED strip are those which come with the strip from TCSS.  I followed the NeoPixel blade building video instructions. 
Should I replace the wires connected between PCB and LED strip with larger? 
Should I replace PCB related wires in the hilt to use 22 or larger?

Still waiting for the battery so all adjustments will be made after next round of testing.

[K-2SO]

Yes, any wiring related to the Neopixels should be 22 gauge.

[jbkuma]

The effect here is that the wires can only carry so much current before they start resisting the flow.  You can measure the drop across the wire.  The longer the run, the greater the loss.  The inch or so of wire within the blade is not as big of a deal.  You can imagine it like a water flowing through a narrow pipe, or breathing through a straw.

I personally use 20AWG.  There is a measurable difference even on a cheap multimeter, measure at the positive connection to the battery and the positive connection to your blade.