maszti

What does BEC offer to you?

mashimarowu

iTrader: (8)

Allows you to give more power to the servo if for example your ESC doesn't have high enough voltage to provide to a servo such as the high voltage servo's from Savox. If not, your system will twitch in and out causing the shutoff known as a brown out.

Genebaby

iTrader: (7)

I updated my ESC FW so it now pushes out 7v, which runs most servos fine. I also don't use Savox, with them an external BEC is recommended.

mashimarowu

iTrader: (8)

Yea just make sure you don't put too much voltage or you can burn up the servo. As for Savox, it is required to have an external BEC when it comes to the high voltage ones.

nofxnz

iTrader: (11)

What is a BEC?
BEC stands for Battery Elimination Circuit and that is exactly what it is.

What does a BEC do?
Before lipos and advances in battery technology, the normal method of powering a receiver was through a seperate NiCd battery pack providing 4.8v to the receiver and servos. As battery technology progressed the BEC was introduced to replace the 4.8V receiver pack (making the model lighter) by drawing power from the higher voltage main pack and dropping it down to 4.8V for the rx and servos. So quite simply the BEC eliminates the need for a seperate power supply for your receiver and servos.

What is the difference between built in and external BEC's?

Generally the BEC found in an ESC is a linear voltage regulator (or linear mode bec), quite simply the way these work is to take the input voltage (11.1V on a 3S lipo) and outputs 5V to the rx. The problem is that it has to dispose of the excess 6.1V and to do this it converts it to heat. Generally these linear mode BEC's are rated at 2-3 Amps, however what the manufacturers do not tell you is that this rating is only true with a 6V input. Using a 3S (11.1V) input the BEC will only deliver around 0.5A before it starts to overheat. Linear BEC's rarely reach more than 50% efficiency and can run as low as 10-15% efficiency.

Generally external BEC's are switching voltage regulators (or switched mode bec), these do not care about input voltage and can run up to around 30V+ input. A switching regulator works by taking small chunks of energy, bit by bit, from the input voltage source, and moving them to the output. This is accomplished with the help of an electrical switch and a controller which regulates the rate at which energy is transferred to the output (hence the term “switching regulator”).

The energy losses involved in moving chunks of energy around in this way are relatively small, and the result is that a switching regulator can typically have 85% efficiency. Since their efficiency is less dependent on input voltage, they can power useful loads from higher voltage sources.

nofxnz

iTrader: (11)

These are good too to fix servo brown outs

http://www.amainhobbies.com/product_...iver-Capacitor

maszti

Folks sorry for late reply. I am amazed your knowledge is so impressing. Thx for explanation.

I am using hitec 7955 servo, do I get any benefit thx to adding BEC to my setup? I am using standard hpi esc in my vorza.

BR
Tomas

nofxnz

iTrader: (11)

You could just use one of these http://www.amainhobbies.com/product_...iver-Capacitor it builds up the power to make sure theres enough power available for the servo etc so you wont get brown outs with your high power servos

Or you could go all the way and get a Castle Creations 10amp Bec http://www.amainhobbies.com/product_...Adjustable-BEC you can adjust it with a Castle Link http://www.amainhobbies.com/product_...rammer-Adapter
Running a Capacitor takes the load off your ESC's on-board BEC, running a external BEC does away with the ESC's on-board BEC all together both give you a more reliable system.

goatsblood666

iTrader: (3)

Honestly Man, if you have decent soldering skills, and the 15 minutes it takes to install, in the long run you will alot happier with the castle bec. I think the speed control puts out 5 volts, with bec you can set it to 6.0 volts. You would be amazed at what that extra volt gets you in speed, and torque. Plus you esc should run a little cooler temp wise! If you have the castle field link, it doubles up as a straight up castle link. Way more bang for your buck! Let me know if you need some pics of the install! I have them for my vorza!

Cadman1981

iTrader: (1)

Hey Guys, i have a HPI Vorza, and it's awesome, i started reading this thread, but at nearly 600 pages, it's going to take a while to get through...

I am looking to reduce the weight of the car. i found this link with many parts http://www.competitionx.com/project-...i-vorza-build/

but is there a lighter chassis? the D8 has a lightweight chassis option, does that fit? any suggestions would be great!

Thanks

mashimarowu

iTrader: (8)

Problem with running just a cap is that if you have a power hungry servo your servo may still twitch or be slow. It takes time for a cap to recharge so if you keep steering, you won't get the full potential of the servo. Bec is prob the best way to go.

maszti

Hey 666 goat bloodgive me what you got. If my solder skill is not enogh I willask myfolks who works for me. I am pleasured work withbest folks all over the world who can repair any electronic equipment you wish. Just let me know what should I do and I will thanks to them. If thereis any chance to improve I will do.

Happy Easter! Thirst time with a plenty snow outside... I am still amaised...

nofxnz

iTrader: (11)

The thing is its only a hitec 7955 you dont need to run anything with it the onboard bec will power it just fine, so cap is just there for back up and a bec would be way over kill. Like Genebaby said you can also bump up the onboard ESC bec voltage with a castle link if using a castle ESC. Caps charge within micro seconds! For instance, if you have a 1 microfarad capacitor and a source that can pump 1 ampere through it, it will charge up 1 volt every microsecond.

I own 2x novak caps, 2x castle 10a bec, castle link, hitech 7955 and 2x HPI SF-32TT, The SF-32TT needs a cap or bec the 7955 does not need anything, I have tested (with tekin rx8) and own these things not just guessing, but yer spend the $43 and make it bullet proof

Buy these 2 parts mazti

Bec setup: $42.98
http://www.amainhobbies.com/product_...=Product-Feeds
http://www.amainhobbies.com/product_...rammer-Adapter

nofxnz

iTrader: (11)

The Tekno V4 D8 Brushless Kit is the best light weight option http://www.amainhobbies.com/product_...D8-42mm-Motors

The standard vorza chassis is a tank, its a whole different car with a Tekno chassis waaaayy better!!!

mashimarowu

iTrader: (8)

Thats what I said "if you have a power hungry servo"...