Do I have to install a BEC ?

[PSH72]

Hi to all, Im new on the crawler world, I bouth a secand hand Maverick Scout, motor and ESC are stock, the receiver and radio is a Ansmann W3 2.4, I have a hacked GT3C but Im running the Ansmann w3 on the crawler at the moment so my dougther could play a little with it at home next to me, she will only turn the direction since shes a year and half but loves car just like dady

Well Im not and expert in electonics, so my douth is I have a absima servo S150MH on it, and Im going to use at the moment a 2s 30C 1020mha lipo that I have at home, do I have to use a BEC, and if so how many amp should I have?

I have this Ubec in the draw, is it the same as a BEC, its 3amp I think its to low as I seen most of you say 10amp.

Best regards

Sorry for my bad Inglesh

[JokersWild]

Yes, castle creations external 10 amp bec is your best bet. There is a sticky up at the top of this list. Having the external bec will save you trouble with glitches in the future if you do not have thrm now. For 20 $ its a good idea.

[TacoCrawler]

IMO... no you don't need an external BEC for your current set up.

But if you change to a 3s LiPo battery,
run a high torque servo 350+ oz/in,
utilize a low wind, high power demand motor,
need additional for power lighting or other gizmos...

You'll likely want one then.

If you get a BEC...
I would recommend getting one that allows for voltage adjustment.
Some are a pre-set voltage only.

The Castle Creations 10 amp BEC is voltage adjustable...
But an additional link purchase is required...
so that adjustments can be made via your PC/Laptop.

Voltage adjustment to the CCBEC
cannot be made without purchasing the CC link.

Combined purchase... about $ 40. US

[PSH72]

Well Im from Portugal, the bad thing is that here there arent a lot of stores of Rc like there is there in the USA our in UK, most of the staff that they sell here are more expensive that if I buy from your stores, even with the shipment.

The problem is that most shipment cost are nearly the price of the produts, I have a Maverick scout, it has some mods done from the last owner, the nihm pack isent that good I have some 2s lipos here at home from my planes I used to have, I can use them in my crawler, and since I have a new Ubec never used laying arround I coul put in, its this one

Turnigy 3A UBEC with Low Voltage Buzzer

I now it isnt near the castle and there isnt no comparison, but if it would do the job, it was needless spending money.

[redsawacs]

Lets start with this......a BEC is what is used to drive the servo and is a seperate circuit inside the ESC, when you add an external BEC you eliminate the internal servo drive circuit from the ESC power so the ESC can concentrate on driving the motor. If you over power the internal with a strong servo or a servo that is working harder than the BEC can handle, your ESC will start glitching.

Ok, so....I agree with Tacocrawler that you do not need a BEC UNLESS you're glitching when you turn the steering. I do not know anything about the ESC (amps, voltage input, internal BEC etc) so it is hard to determine if you need one for your current set up. However, I can offer this...Most ESCs have an internal BEC around 3 amps which is just enough to run a normal servo - not a crawler servo. A crawler servo is absolutely the most abused piece of electronics in the RC world - they draw TONS of power (anywhere from 5-10 amps and higher on the bigger servos) and heat up rather quickly. The bigger servo you have the better for handling the weight of the rig without too much isue. Of course that means you will need more power as well. Typically in the form of voltage and available amperage to handle that. The only way you will get that is if you run an External BEC. BUT, don't run a higher voltage than your servo can handle....unless you like to see it burn up.

If I did the conversion correctly, your servo is around 208in/oz which is considered the "gateway" for using an External BEC. Again, if you are not having issues, you don't necessarily need one. But keep in mind, you're on the edge of needing one.

I do not think the UBEC you have will do you any good - it has about the same amperage as a normal ESC internal BEC.

[PSH72]

Ok, so I should have a minimum 5v ubec our 10v ubec for safty

[redsawacs]

Your servo is only rated for 5v....any more voltage and it will burn up. A 10 AMP BEC would do just fine - amperage not voltage!

[PSH72]

Originally Posted by redsawacs

Your servo is only rated for 5v....any more voltage and it will burn up. A 10 AMP BEC would do just fine - amperage not voltage!

But it says 4,8v-6,6v

Absima AB-2030005 - Absima Servo S150MH 15kg 25T/JR Metal Gear

[redsawacs]

Then you can run a BEC at that voltage. Again, you only NEED one if you are experiencing issues. If you're looking to spend money, buy a 10 amp BEC and set it to 6.5 volts

[PSH72]

Thank you all for the help, this forum is great

[Olle P]

10A BEC is way overkill!
A high power servo will draw no more than 5A peak and typically below 1A. (I've measured my servo's consumption, so there's no guessing here.)
The Absima servo can be expected to pull up to about 2A at 6.0V. (If it's anywhere near my old PowerHD HD-1501MG.)

The only reason for spending $15 extra to get a CCBEC instead of the alternatives is to get the ability to tune the output voltage.
For me it's fine to use 6.0V, so I don't spend that extra money...