Spektrum Firma 100A ESC doesn't work with Savox SB-2274SG

[bukshypro]

I sent back one of these servos, modelsport said it worked well for them but they still sent me a new one. now the new one does the same thing, it lags and just falls behind when testing. I already set my ESC to 7.4A BEC voltage, but it still can't work with the servo.
any ideas?
link to Spektrum Firma 100A ESC https://www.spektrumrc.com/product/firma-100a-brushless-smart-esc-3s/SPMXSE1100.html
link to Savox SB2274SG https://www.savoxusa.com/products/savsb2274sg-high-voltage-brushless-digital#technical-details
any hacks or anything I can do to make this work? I can't see any technical details or specs on neither of the above to say that these 2 wouldn't work together :/


Link to vid, see how sometimes it lags behind. Its exact same behaviour as the previous servo. So its not the servo, its probably the ESC

 

[Xpress..]

Do any other servos exhibit this characteristic when plugged into the same components?

 

[bukshypro]

Do any other servos exhibit this characteristic when plugged into the same components?

I only have the stock Vorteks servo, the Spektrum S651, which works fine.
Older video, but recorded how the Spektrum S651 works just fine

Older vid w the first Savox servo:

 

[RadioHacktive]

Here's something that might help:

"*NOTE: Certain combinations of receiver and ESC have been found to cause "Brown Out" issues when combined with Savox servos. An external BEC, or BEC stabilizing receiver capacitor may be needed for efficient, glitch free operation in low voltage electric applications."

I wonder if this is the case.

 

[Tex Koder]

Here's something that might help:

"*NOTE: Certain combinations of receiver and ESC have been found to cause "Brown Out" issues when combined with Savox servos. An external BEC, or BEC stabilizing receiver capacitor may be needed for efficient, glitch free operation in low voltage electric applications."

I wonder if this is the case.

I think you're right..

Something like this >

 

[bukshypro]

I think you're right..

Something like this >

View attachment 264554

Whats the name of this and where do I plug it?

 

[RadioHacktive]

Whats the name of this and where do I plug it?

That picture is this. According to the description, it plugs into any open receiver slot.

 

[Tex Koder]

That picture is this. According to the description, it plugs into any open receiver slot.

That one is Out of Stock..

Perhaps try this one >

https://www.amainhobbies.com/protek-rc-glitch-buster-receiver-voltage-stabilizer-ptk-2950/p450146

 

[bukshypro]

Sorry people. I live in UK so no amain for me. I am ordering it from modelsport, they got 1

 

[Tex Koder]

Sorry people. I live in UK so no amain for me. I am ordering it from modelsport, they got 1

You could easily DIY yourself a couple of them..

Just need some JR connectors
and
10V 4500uf capacitors

 

[Xpress..]

I would be leery of running a servo that shows signs of browning out with no load on it. You may have to run an external BEC with this.

 

[Tex Koder]

I would be leery of running a servo that shows signs of browning out with no load on it. You may have to run an external BEC with this.

And just to offer a counter viewpoint on that matter..

Some ESC offers better BEC circuitry and could provide more voltage to higher performance servos.. (since that servo is spec-ed as High Voltage..)
The only way for OP to test now would be to connect his new Savox to another ESC (preferably a 150A or 185A unit?) to see if he's getting the similar issues.

 

[RCbuzz]

Something here seems off, unloaded you would think that receiver and ESC could handle some basic movement....

EDIT:

https://www.savoxusa.com/products/savsb2274sg-high-voltage-brushless-digital#technical-details

• Running Current (no load): 180mA @6.0V, 220mA @7.4V
• Stall Current (at locked): 6000mA @6.0V, 7400mA @7.4V
• Operating Travel: 100° (1000 → 2000 µ second)

Stall current at 6amps is too much for that receiver and ESC. You need an external BEC.

You could retest with a proper external BEC to confirm. Servo does sound a bit raspy though.

 

[dk10438]

that ESC can only provide 4 amps....

 

[Tex Koder]

Something here seems off, unloaded you would think that receiver and ESC could handle some basic movement....

Well maybe..
Either the servo itself just naturally draws/demands more voltage to begin with ,or the BEC is not able to keep up with this servo.

Granted this New replacement servo 'could' be faulty too.

 

[bukshypro]

Well maybe..
Either the servo itself just naturally draws/demands more voltage to begin with ,or the BEC is not able to keep up with this servo.

Granted this New replacement servo 'could' be faulty too.

The servo is not faulty tho, since even the previous one I sent back was tested and worked just fine.

So now my question is, does that BEC glitch buster is the thing you call external BEC ? So will that fix ?

 

[RCbuzz]

You are going to need an external BEC for a 6Amp Servo

 

[bukshypro]

You are going to need an external BEC for a 6Amp Servo

Im quite new to this, what is an external BEC ? also is that smth so expensive that it would worth buying another servo instead? This was £90

 

[RCbuzz]

I finally picked up one of those JX servo's that Kevin Talbot likes, not bad and works on stock components. An external BEC allows you run higher amperage devices like this particular servo. It will essentially provide power to the device while allow control from the receiver. Let me try to find one for you as an example.

 

[dk10438]

pro modeler actually lists amp draw at stall
I have the DS630 and it's awesome. I only moved to futaba because I'm running a full futaba set up
Savox are known to be power hogs
https://www.promodeler.com/DS630BLHV