Spektrum receivers require separate llow-voltage failsafe unit..?
 

Pretty sure they do, but can someone confirm?

Can someone suggest any low voltage failsafes? Something that cuts off at 4v for use with 6v hump packs?

Thanks!

errr.. I guess Spektrum recommends receiver voltage alerts at 5.5v: "5-cell 6.0-volt pack = 5.5 volts".

So... any recommendations on good micro failsafe for 6v humpty hump action?

Would this one work? https://www.hobbyking.com/hobbyking/..._function.html

I am thinking it won't work, because 4.2V is too low for a 6V pack. For 6V pack it should trigger failsafe around 5.4V, right? Holla

What application are you going to be using this on?
What is you idea behind running a fail safe? Spektrum has a built in fail safe system in it. Surface anyway, not sure about aircraft.

And a 5 cell hump pack should not discharge below 54ish volts unless one of the cells goes bad.

Using it to power the Rx on my 8ight 2.0 nitro. The Rx is sr201 and twice now my setup has gone rogue and twitchy from low battery. Perks right up again with a fresh one. So I am looking for better low voltage protection.

Savox 1258tg's.

Thanks for the reply!

Got a couple possible solutions for you.

First is the free one. Re-bind you RX and TX. When you bind them, set the fail safe for full brakes so if the issue happens, you wont have a runaway car. Make sure both you RX pack and TX batteries are fully charged also.

Second. Go buy a RX cap for about $8. Spekturm/ Novak and some other companies make them. Pug it into another port on the RX. This will help keep constant voltage on the RX. Savox are known for being power hungry and this has help a lot of people in gas and electric cars.

3rd. Get another RX. It could be as simple as just being bad. Dont know how or why they crap out but they do. Before you trash it, make sure there isnt any dirt in it and try it in another car. Who knows.

And last. Get new servos. Like I said before, Savox are power hungry. I personnaly didnt like them and switched to another brand. But I know people who swear by them.

Good luck.Le us know

As I understand it Spektrum failsafe only protects against loss of radio signal, not loss of receiver pack power. A receiver cap won’t help a dead receiver pack much.

Lower power draw servos as mentioned would help. Or perhaps a larger receiver pack and/or be more diligent in tracking run time and changing out packs.

Failsafe on the SR201 is set, works great for signal loss.

As Dave H says, I have also read Spektrum rx's do not have low voltage protection and thus they recommend micro failsafes. My problem is most micro failsafes I find that specify what voltage they kick in at say around 4.2v, which is too low for 6v hump which would need failsafe to kick in at around 5.4v.

And, yea, can't use a cap since its a SR201 and no available ports.

I am hoping to not have to learn the subtle emotions of my hump packs to be able to tell when they *may* be low.

I guess going LiPo with regulator for rx would solve all this, but.... $$$. And I stumbled into some new 6v humps for free I'd like to use as long as I can.

I feel like I am missing something... this should not be this complicated.

I'm in the same boat really. My failsafe for some reason is set to full throttle. Tons o fun in the park, street, house, backyard with a pool, etc. I'm going to re-bind it tonight and reset the failseafes to neutral as CC told me. Sucks to know I can't use a BEC as the only open port is the bind. Going to try a cap just for chance as well. Also have to figure out how to move my rx further away from the engine and esc which takes up the majority of room in my m8.

you can use a Y connector to essentially get you another port.

Actually I think we have different issues. As you said, you should be able to re-bind with proper failsafe settings easily (just have your radio at full brake when binding, or if your system has a reverse have the throttle at neutral while binding).

My issue is erratic throttle and servo behavior when rx battery gets low. For now I have set a low voltage alert in my dx2s using telemetry. But failsafe settings don't really apply once your rx battery is dying, they are only for loss of radio signal. How could it go into full brake if it doesn't have the juice :)

My Spektrum SR201 seems that it has fail safe for low voltage. At least it did cut off and applied brakes when my Rx battery (that I forgot to charge) was at about 5.5 Volts.
And that's one of the cheapest receivers.
It wasn't due to lost signal.
I would call Spektrum or rather Horizon and check on that with them.