Better way to ask the question...2 batteries

[hapki]

I asked a similar question previously, which FJK was kind to answer. I'm still working on th concept here, so thanks for bearing with me. I know th PEx converts a weak current to a more powerful one. I assume it does this by drawing current from the battery power supply. My questions this: does one have to use the same battery for both the PEx and sound board? In the words, could one power the PEx with a second battery? But perhaps the PEx needs to be grounded to the sound board?

[sgcdialler]

I don't see why you couldn't do it that way, unless I'm mistaken. I assume, based on your previous thread, that you're trying to find a way to power that 6th LED channel?

[Forgetful Jedi Knight]

Why don't we get specific here. Exactly what kind of LEDs are you trying to run?? 6th LED channel???

[hapki]

Yes, the plan is to build a saber staff using one CFv7.5. I could wire LEDs for each emitter n parallel, but I'm worried that my run time will be too short. I thought maybe I could power the FOC diodes with a different battery. Since it is a staff (about 24" long), space isn't as much of an issue.

[sgcdialler]

Ok, let's get more specific. What colors? Something like a GGW or BBW, etc., on both ends? Or are you wanting to do RGB on both ends?

[hapki]

Sorry, I meant QUAD. If one die on each emitter was white, I could use it as an on-top FOC and power it with a separate battery through the PEx. I'd probably need a diode between the board and PEx to keep the current from flowing back into the sound board.

[hapki]

And if I could solve this problem, it might lead to different ways of using dual batteries in other ways. I'm always trying to push the envelope by trying new things.

[Forgetful Jedi Knight]

And if I could solve this problem, it might lead to different ways of using dual batteries in other ways. I'm always trying to push the envelope by trying new things.

A PAIR of quads no less, huh?

[sgcdialler]

A saberstaff, running an RGrBW quad LED on either end for color-changing blades with white-on-top FoC, powered off of two batteries, controlled by a single CF7.5... I'd say that's pushing the envelope. Let me think for a bit and mull over the manuals.

I know you hate the 'more is brighter' argument FJK, but I don't think that's what he's going for here.

[hapki]

I've decided to go with a PRIZM on one end and the CFv7.5 on the other. It'll be two completely different setups. I happened to have a PRIZM I'm not using. Then I'll just use a COPPERNOVA RGB LED in each emitter. Ideally, I'd use two CFs, but that's a lot of $$ for one build. I'm not sure if the colors will match, but I can tinker with it. I have a CEx for the CF, and I may be able to get another one for the PRIZM. maybe that way I can get the colors to synch. Too bad I'll have to change colors one blade at a time though. I wish I could change them both at the same time, maybe by using the same aux switch for both? That could get confusing.

[Forgetful Jedi Knight]

Prizms don't use CEx's. ;)

[Scarecrow]

Don't run that setup. Those boards use different batteries, sensors and drivers. You'll have a hard time getting one color to be the same on both blades, much less 10 profiles. The prizm will change colors as the battery drains, too. Go back to the CF with Cex run parallel on both sets of dice. If you're worried about run time just add another battery. It will help the run time and also help balance the weight of the hilt. Run the batteries in parallel. You will have to ask around about wiring two packs. I think you might need another pcb between and if so, I don't know which one. The biggest drawback I can see is FOC, blaster block and lockup will be on both blades instead of independently. Then again, in a two board setup I don't know how well the sensors could differentiate between one blade or the other for FOC. Hope this helps a little

[hapki]

OK, thanks.

[hapki]

Using two batteries sounds like a good solution. Thanks for the guidance. That actually solves several problems. If anyone has info on how to wire up two batteries to the CR, please share. I'll start searching the forums for now.

[hapki]

Thanks again for the advice, FJK and Scarecrow. I've decided to put two 7.4v Li-ion 2600mAh 18650 Battery Packs in the hilt, but only connect one at a time. The other will be a spare. When the first one runs out, I'll just disconnect the JST and connect it to the new battery. That'll help balance the hilt, give me extra run time between charges. I'll have to re-charge batteries separately, but that's do-able.

[Scarecrow]

Glad to help. Sorry I don't have a battery solution but I think you have it figured out. Just be sure to secure your extra battery lead when you're not using it. Otherwise, it will be flopping around in the hilt.