Hoverfly Powering the board with 6s

yeehaanow

Member
I think it's a great feature to power the board off the main packs and have that info on the OSD.
But if you use a 6s system that creates problems. Currently, i'm using a CC BEC connected to the main power, but that won't show pack voltage obviously.
Is it possible to tap the main packs from the balance connector using one of the lower voltage pins, and thereby seeing "pack" voltage?
Or does that create a short?
 

yeehaanow

Member
Anyone do this? Is it possible?
I would like to eliminate the BEC powering the board, as it's just another piece of electronics that could bring it all down.
 




Photronix

Pilot
The Official Answer: The manual states that you should not exceed 5S. Hoverfly recommends that you adhere to this when operating the HoverflyPRO.

Now the unofficial answer is this: The HoverflyPRO can handle voltages up to 32V or 7S (at full charge). HOWEVER, the voltage regulators will get warm about 50C. You can try to add a small heat sink on the voltage regulators (some people have done this) to help dissipate the heat. However, you will run the risk of failure while flying. So be advised, technically it should be fine at 6S but you must be aware of the risk involved.
 

workshop

Member
Al,

Can you point out the regulators for those not familiar with the parts. As I recall, they are SMD so that is a tiny heat sink.

So the GPS is fully powered by the HFP?

Jeff
 

Photronix

Pilot
The GPS also has the same regulators and would need to be cooled using a second heat sink.

They look like this and there are two of them on the PRO and two on the GPS.

I am not suggesting that you add a heat sink and I can't help you any further. I recommend that you use 5S.

View attachment 6417
 

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yeehaanow

Member
Thanks for the responses.
My question was really if it's possible to tap the balance lead of the battery to get 3s, 4s, or 5s out of it. I wouldn't want to run full 6s power.
 

jrlederer

Member
Thanks for the responses.
My question was really if it's possible to tap the balance lead of the battery to get 3s, 4s, or 5s out of it. I wouldn't want to run full 6s power.
I'm not absolutely sure that I understand your question fully, but it seems to mean that what you're trying you may be accomplished by using ATTO current/voltage sensor, but again I'm uncertain as to the exact meaning of the original question.
 

jrlederer

Member
Stopped by to check for progress in the thread and happened to realize my post count next to my name. Figured I might as well round it off to a solid hundred!!! Yeah!
 

yeehaanow

Member
What I'm asking-
You can isolate each cell depending on which pins you use from the balance plug to arrive at at a voltage from 1s,2s,3s,4s,5s and finally 6s. So, tapping pin 1 (neg) and pin 4 (Pos), you get a voltage of 11.1v.
Hope it makes sense now.
 


workshop

Member
I was just asking for clarification for folks that don't know what a regulator looks like.

I fly 3 and 4 cell systems but our company's SkyJib uses 6s batteries and wondered about direct voltage for OSD readout purposes.

It would be nice to use HFP with higher voltages and still get the voltage displayed on the OSD. The ONLY think I like about the WKM system is the remote power supply, LED and USB module that allows a user to "remote" the LED and USB ports and have a voltage regulator that works with higher cell counts.

Jeff
 

yeehaanow

Member
A regulator should drop in output voltage as the input voltage drops, but they tend to heat up a lot when a larger voltage drop is required.
A converter, or BEC like I'm currently using, will compensate to maintain constant voltage output.
I'm looking for the most reliable system that also shows pack voltage on the OSD, so plugging into the balance plug of a battery seems like it would be the best option... I'd it's possible.
 

workshop

Member
Not true!

All voltage regulators regulate voltage. By definitiion, the input voltage varies and the output voltage is regulated to a constant value. Linear regulators generate (waste) more heat than a switching regulator but switching regulators generate R.F.I. (some more than others).

The designer has a choice: efficiency and possible RFI with nearby components with a switching regulator or clean power at the cost of efficiency with a linear.

Jeff

Reading cell voltage from a tap lead should be no problem at all.
 


S11D336B

George - Hoverfly
I highly recommend that you get a Castle BEC and set it to 9v. Power the Hoverfly with the Castle BEC. This way you can use whatever voltage battery.

Thanks for the responses.
My question was really if it's possible to tap the balance lead of the battery to get 3s, 4s, or 5s out of it. I wouldn't want to run full 6s power.
 

yeehaanow

Member
I highly recommend that you get a Castle BEC and set it to 9v. Power the Hoverfly with the Castle BEC. This way you can use whatever voltage battery.

Yes, that's what I'm doing now, but I would like to have the battery monitoring feature on the OSD.
I really needed it the other day when I flew a bit too long and did not have enough juice to land smoothly. Luckily the ground was soft and nothing was damaged.
I guess a simple lipo monitor will work too, but that's just more weight.
 

Bartman

Welcome to MultiRotorForums.com!!
for anyone that isn't following the original post, yeehaanow is thinking about using a 6 cell pack which would normally be too high voltage wise for the board to handle directly from the pack. the ESC's can handle it just fine so he has to use a voltage regulator set to a lower voltage to power the HF PRO board. To get voltage information from the pack though he's considering pulling voltage from a few of the cells through the balancing tap and letting the HF PRO's resident on-screen-display show him that voltage (4 of the 6 cells for example). This would be representative of the cells even though he wouldn't be seeing all six cells. It's a pretty ingenious idea.

Maybe I read it wrong though, maybe he's considering powering the board from the balancing tap using only a few cells? The board probably uses a very small percentage of the overall power consumption thereby not putting the pack at risk of being flown out of balance by the end of the flight. So 6 cell power would be put through the ESC's and 3 of the 6 cells would power the board via the balancing tap? Is that what you had in mind yeehaanow? 3 cells being 11.1 volts and a low power condition of 9.9 on the OSC would be the signal to land.

Bart
 

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