installing a BEC

[vega856934]

Here is the two ways i know to install a BEC. If you see that I did not get it right let me know. If you like it you can share it if you want.

[SMR 510RR]

1. The writing should say that you need to "pull" the red wire rather than cutting it. Its a lot easier to put it back in the plug then solder it back up.
2. You are showing a ground from the servo to the RX in the second diagram. While it is sometimes necessary you should note that it is not typically needed.

[ZippoMan]

For me I pulled the red wire back then cut it!! I have no need to put it back to stock. I will get a different ESC. I have mine wired like your top diagram. It works!

[JohnRobHolmes]

Either way works well. If you keep the ground loop you are less likely to develop floating ground and glitching, although it is a rare occurance since servos use PCM control. It is still good electrical practice.

I prefer method one for general systems that aren't crazy on the servo power, IE systems with less than 400 ounce/ inch of servo power. I run all of my play rigs like this. Method two is good for comp crawlers that want the least electrical losses, and I would consider it absolutely necessary on today's modern super sized rigs that run four servos unless RX modification is done.

[vega856934]

sorry it took a long time to up date it but I think I have it done. I want to say thanks to JohnRobHolmes and SMR 510RR for help getting it right.

[t3yf5g]

I got a wraith by trade and the BEC is wired into the battery leads then a y-cable plugs the BEC and ESC into the receiver. Is that correct? When I get my MMP, is a BEC still necessary with the castle link?

[mammoth]

Rule of thumb you always need a bec!!!

[t3yf5g]

Originally Posted by mammoth

Rule of thumb you always need a bec!!!

It is definitely a cheap safety net for sure. Does the layout I described sound correct?

[mammoth]

Sounds correct. Just make sure you never have 2 things sending power to the receiver. That is #1 priorty when wiring up a bec. If your powering the servo direct form the battery then the esc powers the receiver. If your bec is plugged into your receiver then the red wire from your esc should be pulled form the connector bent back and taped up or shrink wrapped. The diagrams above are right and you should follow them.

A bec is NOT a saftey net more a requirement!!! Anytime you get to around 200oz of torque and above you will need a bec as the factory built-in bec is not designed for heavy amp draws that our trail and crawlers demand!!!! Not running a bec can fry your esc or even your servo!!!

If you have any worries post a pic or 2 and I or someone will walk ya thru it!!!

[chris78cj7]

Some of the bec are ordered with different volts. What do you suggest for volts?

Sent from a Galaxy far far away

[t3yf5g]

Originally Posted by mammoth

If you have any worries post a pic or 2 and I or someone will walk ya thru it!!!

Thanks, I will post up a photo tonight. I want to redo the wiring to make it nice and clean when I get my new esc and motor in.

[mammoth]

If your getting a castle bec then the programmer will be required to set the voltage as they come set to 5.5 volts. The voltage setting will be determined by the servo you are using. Most servos will run 6volts but several high voltage ones will run 2s so I set mine at 7 volts just under the 7.4 volts that a 2s is ( I also run overkill for servos so don't need full voltage). There is some discrepency if a 2s capable servo can run at 8.4 volts or should it be at 7.4 max. The only servo I have seen that has printed 8.4 is this one Hyperion Servo
It is a grey area that I wish the manufactures would just let us know!!!

Also you should not run more then 6 volts to your receiver as most are only rated for that.

Just to see what Hitec is going to say I sent an email asking for the highest voltage I use a 7950 at as the package says 2s capable which to me means 8.4 volts. I will post the results of the email once I get it.

[ik632]

Originally Posted by mammoth

Rule of thumb you always need a bec!!!

The first rule of rock crawler club is: you always need a BEC
The second rule of rock crawler club is: you always need a BEC

[t3yf5g]

I have a Savox 1256tg and looks like 6v is it's max. I only have a 3s lipo so I know I am pushing a lot of power through. I will need it when I get my pro4 in

[Solitaire]

Diagram two is necessary if you're running Spektrum gear. I've tried diagram one on two separate builds and it didn't work with a DX3C and SR300.

[mammoth]

By far the simplest way to add a bec No Brainer BEC dosen't get any easier and just let him know what voltage you want and it will come that way!!! I have one and find myself constantly using it to test servos besides being used in my kids honcho!!!

[ik632]

I do diagram 2 on my trucks. I like to run all 3 wires of BEC to servo, then ground and signal from servo back to receiver. Then, let ESC BEC run receiver and lights on my Wraith.

[t3yf5g]

Originally Posted by mammoth

If you have any worries post a pic or 2 and I or someone will walk ya thru it!!!

Here is how the BEC is wired in

[RusT808]

Here is how I did mine, works fine. Same as the 'No Brainer' style.

[Tonysmini]

I've got a couple of these Y harnesses, I never thought of pulling the red wire from the RX end. You just saved me ordering a couple of the HH harnesses and getting stung by customs in the UK too.