4S LVC and BEC Questions
 

I have a 1/16 E-Revo VXL. I'm making some changes to it and have a question. I am planning to run an EZRUN 60A esc at 4S. I understand this will require at external BEC. I had my eye on the Castle BEC, but would like to know if there is an all in one BEC/LVC I can use. I would prefer something small and clean, instead of two seperate modules. I'm guessing this would be the same dilemna faced by those that have pushed the MM to 4S, right?

Any ideas?

Thanks

BEC and LVC are two completely different items doing different jobs, affraid theres no all-in-one solution.

Depending on the units you by, they can be very small and descrete though, just gotta shop around ( I have LVC ideas in my Tutorials page, see my sig).

Thanks, I will look at the tutorial now.

I just found this SmartBEC. Would that be a viable option for me?
http://www.dimensionengineering.com/SmartBEC.htm

Unfortunately, that is designed for aircraft ESCs, which uses a different throttle range profile.

Bummer...thanks for the info though. So, I guess I am on the lookout for a very small BEC and LVC. The truck really doesn't have much space.

What about using a sidewinder ESC with an external BEC? It at least has the LVC built in.

How much of a rush are you in? You could wait for the MMPro. It will have a switching BEC, LVC, capable of 6s lipo, and pretty small (more so if you remove the fan).

The EZRUN has an LVC, but I assumed it would only work up to 3S. I do not have the esc in my hands yet to verify. Will the Sidewinder LVC work for 4S, even though that is not officially supported? I know, lot's of question...but I'm learning :)

That I'm not sure of, but I'd imagine it's based off the MM (just fewer FETs) and the MM works up to 4s (and over sometimes) if the BEC is disabled.

I think the 60A has LVC for 4s. I have one but don't remember the LVC settings as I haven't played with my esc in a while.

OK, I guess for now, I'll just worry about the BEC. Is the Castle BEC super overkill for this application? It will be running the receiver and one miro steering servo :smile:

Thanks again, for all the info.

I use the cheap BECs from hobbycity and they work fine. I think the CC one is a bit overkill but it can ne used for other things in the future.

Size-wise, the DimensionEngineering ParkBEC works well. I use one in my CRT.5, 4tec, and was using one in the Slash (now use an ESC with a UBEC built-in). So, plenty for 1/16 scale.

+1 on the ParkBEC, I run one in my 1/8th buggy with MM, spektrum, and Hitec 5645 MG digital servo!

You guys running the 6V version?

yep 6 volt, just be sure your servo can take 6 volts (some micro's can't).

Yes...

I'll be running the HS-5085MG, I think it should. So, if I have this hooked up and decide to do some bashing at 2S, do I have to remove the ParkBEC? The 6V ones says something about not working with 2S packs.

Yeah, pretty much any switching BEC needs at least 1.5v higher than the output to work right. If it has a 6v output, you'd need at least 7.5v all the time, which won't happen for very long on 2s.

The one nice thing about the DimensionEngineering BEC is that it has a throttle signal pass-through feature. When using 3s, you hook your throttle to one side of the UBEC and the other end goes to the receiver. Use something like a servo connector, mini Deans, etc for the BEC battery wires so you can remove it easily. So, when you want to run 2s, just remove the BEC and plug the throttle cable directly into the reciever.

OK, so I will wire it in with a quick disconnect of some sort. I'll be running this with a Ko Propo 2.4Ghz receiver (KR-407S). Can I mount the BEC right next to the receiver, to make it easy to swap the ESC from the BEC to the receiver quickly? Or will this cause interference?

Thanks again for all the help.

You should be ok. 2.4GHz is quite resistant to noise (at least at the frequency the BEC runs at), and the DimensionEngineering BEC is just about noise-free. But you never know. Try it and see. If you have range problems, or other odd things, let us know because there are things you can do to reduce/eliminate the noise depending on where the interference is coming from...

Alright, sounds good. I want to mount it right next to the receiver, just for packaging reasons. When I run 2S, I can swap the esc plug from the UBEC to the receiver and be all set.

BTW, I found somewhere else where somebody had mentioned the EZRUN LVC does work at 4S, so I should be all set.

Just gotta decide which Neu motor I need now, but that's another post...

Thanks again.

why should that matter? the ubec/external bec is providing 5v current, no matter what throttle the esc has.

Well no, the BEC doesn't matter, but the LVC part does. Aircraft throttle signal goes from 1ms (neutral) to 2ms (WOT), but cars go from 1ms (brake/reverse) to 1.5ms (neutral) to 2ms (WOT). When the LVC kicks in and goes to neutral, it would actually be sending a brake/reverse signal to the ESC if this was used on a car ESC.

aha. I used to have this indiv. lvc-thing (made by "robbe"), but never got it working properly on my cheapo-plane esc. or I am too stupid... it has a button, to do a setup and to "tell" it what to do when there is a lvc.
fortunately, the lvc of the esc works well.