Changing BEC voltage

[chrisansilver]

Only change I want to make to my helijive is the BEC voltage, what do I need just a program card or program disc? Thanks in advance..

[Slyster]

It only goes up to 6v... You will never notice the difference of .5v... and from what I've read, it only gets less reliable (needs the nimh backup)

[Vinger]

Progcard 2 or the ProgDisc, but leaving it at 5.6V is recommended as posted by Slyster. It just works even with HV servos.

[chrisansilver]

The reason for wanting to change is because I'm flying HC3SX just trying to eliminate and unwanted shut down of HC. Minimum voltage is 5.5v for the controller, thought I would bump it up to 6.0v. I ordered a program card II from RH will give it a shot and see how performs.

[Slyster]

Remember the stock setting is set to 5.6V. I can't imagine a .4v will make a difference even in your case...wow the HC's minimum voltage is really high. Concerning voltage sag, are you using power hungry servos like Align/Savox?

But if you do it, remember what the manual says... For BEC voltages exceeding 5.6V a redundant receiver DC current supply should be connected.

[chrisansilver]

I am running bls451's and a bls251 on the tail, very good serves. I'm running the same set up on my E7 and haven't had any issues to date. Just thinking, is it really recommended to run a back up dc supply for just bumping up .4v on the ESC?... .4V isn't much...

[Slyster]

Yeah .4v isn't much... but the manual does state you need backup as copy/pasted above. Maybe adding the redundant DC current supply will help in your case. I am unsure how power hungry the Futaba servos are.

[Magneto]

I have ran BLS 251,252,253 @5.8- 6v no problem on the Jive, so 451 and 251 combo can be ran higher than 5.6 . Futaba brushless servos doesn't draw much current compared to some other servos on the market.

[jhheli]

Originally Posted by Magneto

I have ran BLS 251,252,253 @5.8- 6v no problem on the Jive, so 451 and 251 combo can be ran higher than 5.6 . Futaba brushless servos doesn't draw much current compared to some other servos on the market.

+1

[CZorzella]

Originally Posted by Slyster

Remember the stock setting is set to 5.6V. I can't imagine a .4v will make a difference even in your case...wow the HC's minimum voltage is really high. Concerning voltage sag, are you using power hungry servos like Align/Savox?

But if you do it, remember what the manual says... For BEC voltages exceeding 5.6V a redundant receiver DC current supply should be connected.

Concerning the use of a redundant receiver DC current supply, IMO, the manual isn't clear enough about this matter.

I've contacted Kontronik support team and they have clarified that "The 4-cell NiMH battery can be connected additionally. Please make sure, that the JIVE BEC is set to 5.6v (default)."

The voltage of a fully charged 4-cell NiMH battery matches the voltage provided by the Jive BEC when set to 5.6V; My guess is that this is supposed to level the potential difference between both electric sources.

[Magneto]

A buffer pack is not needed for this application myself and others have ran Futaba servos @5.8-6v on the jive BEC.

[CZorzella]

Originally Posted by Magneto

A buffer pack is not needed for this application myself and others have ran Futaba servos @5.8-6v on the jive BEC.

Magneto,

Please clarify if your statement is made on behalf of Kontronik or not.

Are you saying that whatever is written in the Jive's manual and also that whatever the Kontronik support team instructed me to do isn't mandatory?

[Vinger]

If you are using servos with a high back EMF, then the chances are that the protection circuit will see more than 6.3V and shut down the BEC. With it set at 6V you are closer to the shut down point. Futaba BLS servos are known to have low back EMF, and can reliably be run at 6V. Align, Savox and a few other servos will shut down the BEC.

It has nothing to do with current, the buffer pack stabilizes the voltage for these servos. I have used Hitec 7940 TH and JR coreless servos and have logged above 10 A of current without a problem.

[Magneto]

Quote If you are using servos with a high back EMF, then the chances are that the protection circuit will see more than 6.3V and shut down the BEC. With it set at 6V you are closer to the shut down point. Futaba BLS servos are known to have low back EMF, and can reliably be run at 6V. Align, Savox and a few other servos will shut down the BEC.

It has nothing to do with current, the buffer pack stabilizes the voltage for these servos. I have used Hitec 7940 TH and JR coreless servos and have logged above 10 A of current without a problem. +1 Czorzella I am addressing the OP .

[CZorzella]

Originally Posted by Vinger

If you are using servos with a high back EMF, then the chances are that the protection circuit will see more than 6.3V and shut down the BEC. With it set at 6V you are closer to the shut down point. Futaba BLS servos are known to have low back EMF, and can reliably be run at 6V. Align, Savox and a few other servos will shut down the BEC.

It has nothing to do with current, the buffer pack stabilizes the voltage for these servos. I have used Hitec 7940 TH and JR coreless servos and have logged above 10 A of current without a problem.

Vinger, thanks for the clarification.

May I conclude then that if you are unsure about the EMF of your servos, that besides of the additional weight the model will have to carry, the 4-Cell NiMh pack may actually prevent BEC shutdown in situations you described. Is that correct?

[Magneto]

Yes if your unsure set the BEC to 5.6v and use a buffer pack . What servos do you have?

[Vinger]

My personal opinion, no buffer pack required with default voltage of 5.6V. Only if you want to use 6V and servos with high back EMF is the buffer pack required.

[Magneto]

More info here about the jive BEC and buffer packs http://jlog.hacknet.eu/jlog2/faq/art...bec-stutzakku/

[CZorzella]

Originally Posted by Magneto

Yes if your unsure set the BEC to 5.6v and use a buffer pack . What servos do you have?

Sailplane
4x MKS DS 6125 Mini
2x MKS DS 6100
Motor Kontronik Kira 600/22 6,7:1
ESC JIVE 100+LV

Heli
3x Align DS510M
1x Futaba gyro GY-401
1x Futaba S9257 with stepdown to 5.4V
ESC JIVE 100+LV

Do I need NiMh buffer pack in these cases?

[garyji]

So, if I'm running 4 RJX servos, and an AR7200BX at 5.6V, does anyone see a problem with using a Scorpion Backup Guard as extra insurance instead of the NiMh buffer pack. I know this has been hashed before, but wanted some updated opinions. (Also, I have the guard already in the shop).

Thanks,

G.