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Old 06-03-2015, 05:11 PM   #1
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Default Electronic Problems? You probably need an External BEC

Having problems with your rig? Steering shutting it off? Want more steering power, any strange glitching, radio, servo, ESC, or motor problems? If you don't have an external BEC (such as the Castle Creations 10 amp BEC) and are driving a truck off road and experiencing any problems, you probably need to get one.


You may also consider a BEC to servo connector or bypass adapter that lets you route power direct to the servo but not through the RX, for better power to servo and also reduction of brownouts by separate RX power.

BEC to Servo connector

Last edited by JohnRobHolmes; 06-05-2015 at 10:52 PM.
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Old 01-08-2016, 09:48 AM   #2
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Default Re: Electronic Problems? You probably need an External BEC

So how exactly do I decide when I will need a BEC? I'm new to the hobby and planning on getting a Twin Hammers and running your BLE Pro (side note: when are you going to have more of the waterproof ones in stock?) For a steering servo I am thinking of running a Hitec 7950. I think I'm going to run your 3500kv Puller Pro BL on 3s and maybe 2s on occasion.

That servo says it can do 7.4V and 3s is obviously more than that, but there is no amp rating listed. Your BLE ESC says it has an internal BEC, but to use an external one for high current servos, but doesn't specify a current limit for that either. But then on 2s could I just hook the servo straight to the battery pack skipping a BEC?
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Old 01-08-2016, 10:10 AM   #3
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Default Re: Electronic Problems? You probably need an External BEC

We will have waterproof BLEs back in stock within a few days, they are just going through the WP process and we don't allow purchases unless items are ready to ship. It is always best to contact us direct with stock questions, as I cannot always respond through RCC or social medias.


I have found the break point around 300 ounce inches for needing an external BEC. Servos rated for 8.4v can use 2s lipo power direct. Current rating on an internal BEC is very tricky, as temperature changes affect output. And being hidden inside an ESC means it has to deal with the temperature swings of the ESC. So get an external one and there is no worries.
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Old 01-17-2016, 02:44 PM   #4
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Default Re: Electronic Problems? You probably need an External BEC

John or anyone for that matter,
I'm running a BLE WP ESC in my wraith. It has a CC 10A BEC set to 7.4v powering the steering servo. My question is regarding the internal BEC, from what I can discern it is only powering my lighting circuit.

How high can I safely set the internal BEC to brighten my lights without damaging either the ESC or the receiver?
I have a 10 led light bar, 2 "fog" lights and an array of SMC5630 rock lights, all rated for 12v.

Thanks,
Jeff
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Old 01-17-2016, 02:59 PM   #5
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Default Re: Electronic Problems? You probably need an External BEC

Cancel my prior question. I've ordered a couple step up transformers off eBay. After reading a few more posts I believe this may be the way to go.
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Old 06-18-2016, 12:57 PM   #6
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Default Re: Electronic Problems? You probably need an External BEC

So I have always had a BEC in my trucks, but I'm thinking about the castle mamba monster x. It claims to have a strong enough internal BEC, at 8A, up to 8v, the MMP has a 3A rating, and the regular external BEC is rated to 10A. I am not running any other electronics other than the RX and the servo (HH500). Will I need an external BEC?

Last edited by Turtlejon; 06-18-2016 at 07:40 PM.
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Old 06-19-2016, 07:56 AM   #7
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Default Re: Electronic Problems? You probably need an External BEC

Depends on how clean your rx power is. Best to power the radio and servo from separate digital supplies. Any load on the servo will interrupt whatever power feeds it.
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Old 06-28-2016, 12:04 PM   #8
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Default Re: Electronic Problems? You probably need an External BEC

Quote:
Originally Posted by JohnRobHolmes View Post
Depends on how clean your rx power is. Best to power the radio and servo from separate digital supplies. Any load on the servo will interrupt whatever power feeds it.
Hey John , Thanks for supporting OUR insane addiction man
I am at the point where im installing the electronics in my XLX..
I'm building a multipurpose 1/8 mountain basher
My Yeti XLX should be a beast in crawl mode HC IFS/IRS, 9" rock loc comp tires, 4 wheel steer, 2 speed , 9/68 , T8 sensored 1700k.v + MMX, 7950TH front and back...

I'm a nubb .. but I have a variety of life experience that helps understand the mechanics/electronics..
This is what I was planning to do..
Install the E.S.C in the (REAR) receiver box with a fan under the E.S.C to keep it cool . This will shorten my power supply wires tremendously which Thomas from c.c said will help with ripple flow ?... My E.S.C will power just my RX .. What is the optimal power for a TX ? I'm using the traxxas TQi TSM blue t.. for the 2 speed transmission, duel steering ports, and tsm/telemetry .. I'm sure its not the best but I'm a nubb... I plan on running 2 separate battery sources (nano turnigy 2200 4s) for my two 7950th, led bar, headlight buckets, shifting servo, Traxxas OBA, and 5 c.c cooling fans... Im using my 2 smaller battery boxes on my XLX chassis to house the power source .. I also plan on running 2 becks for adjusting individual power in side of my (Front) receiver box . One of the fans is used to cool the B.E.C's because it said they should be exposed to 5 m.p.h wind.. I want to keep them dry yet cool ... I seen some b.e.c burn-ups that I've think were related to the C.c warning... Is this overkill?
I also was planning on running just the signal wire from the RX to the servos.. Will this work or could voltage from my separate power source back feed?
Am I also able to use my 2 way toggle 5 ch. for a signal wire for my lights and OBA sound ? Yet still maintaining a separate power source ? I've decided to run the XT 150 instead of deans. I like how the series wire connects directly ..I was also wondering .. will I have a need to run parallel when I'm crawling with the sensored set-up?
And my biggest question.. Will you ever move into the 1/8 ~ 1/5 market ... I'd like to be your first customer
Feel free to tear it apart and give your .." This is what I'd do "
Thanks again !! I'll understand your busy so when ever you get time I'd greatly appreciate it !!






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Old 09-21-2016, 12:13 PM   #9
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Default Re: Electronic Problems? You probably need an External BEC

Hey guys, im sure this has been asked 1million times. A buddy convinced me to install a castle bec on my bomber. we fought with the bec trying to get it working but to no avail. The truck went down to half power and wouldn't get out of its own way. After some research he said that we needed to "Program" the bec but didn't know how. does anyone have any advice on how to or a link to the instructions because im defeated. I removed the bec until I could re-install it properly.

Thanks


I broke rule number one by making adjustments to my truck before a comp.

I broke rule number 2 by listening to a buddy that "says" he knows how to do it.
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Old 09-21-2016, 01:00 PM   #10
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Default Re: Electronic Problems? You probably need an External BEC

All you can "program" is the output voltage, I believe they ship set to 5V? That's most likely the same voltage that your ESC was providing from it's internal BEC.

You hooked something up wrong. The BEC has nothing to do with powering the motor.
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Old 11-17-2016, 05:19 PM   #11
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Default Re: Electronic Problems? You probably need an External BEC

Can someone elaborate on how to either power the servo directly or power it first ?

I have a Baja that the steering servo quivers like crazy - I just bought a Racers Edge Glitch buster to see if that will work???
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Old 11-17-2016, 05:55 PM   #12
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Default Re: Electronic Problems? You probably need an External BEC

Get a Holmes fix..... I run this on all single servos, also a double for dual servos.
Bec powers servo directly, no power to rx as esc provides its power




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Old 07-04-2017, 11:18 AM   #13
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Default Electronic Problems? You probably need an External BEC

I run an external Castle bec on all my rigs. I use Hitec, Holmes, and ProModeler servos , all run at 8.4 volts. I am happy ! Then I read this and learned more. Good read!

http://www.promodeler.com/blog/The-case-against-BECs


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Old 07-06-2017, 07:37 PM   #14
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Default Re: Electronic Problems? You probably need an External BEC

Hi, love the Holmes electronics!

I'm at an impasse. I just bought your BLS HV500. Love it on 6 volts. The problem is, my 2 speed shift servo maxes out at 6 volts but I'd like to set my BEC (castle 2.0) at 8.4 to power the hungry beast..

What do I do?

Thanks!

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Old 07-06-2017, 07:53 PM   #15
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Default Re: Electronic Problems? You probably need an External BEC

Use the bypass to power the steering servo directly from the BEC then let your ESC power the shift servo thru the receiver.
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Old 07-06-2017, 08:02 PM   #16
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Default Re: Electronic Problems? You probably need an External BEC

Quote:
Originally Posted by calcagno45 View Post
Use the bypass to power the steering servo directly from the BEC then let your ESC power the shift servo thru the receiver.


Worst case you might need to run a cap for the shift servo, set EPs carefully


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Old 10-27-2017, 09:09 PM   #17
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Default Re: Electronic Problems? You probably need an External BEC

Having issues with HH BLE, CC BEC, savox servo. Almost seems like the BEC is cutting out? Full left or right turn, touch throttle and the steering servo “backs off “ starts to turn slightly the other way? BEC light is on.


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Old 10-30-2017, 10:36 AM   #18
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Default Re: Electronic Problems? You probably need an External BEC

savox servos are really really dirty EMF emitters and can brown out CC BECs if stalled too long. Be sure your endpoints are set so the servo isn't stalling at the ends, that is the biggest issue to look out for.

Is the BLE powering your radio, and CCBEC powering only the servo?
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Old 03-19-2018, 12:10 PM   #19
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Default Re: Electronic Problems? You probably need an External BEC

I have a mks hbl 380 servo and run 2s with the mamba max pro. Do I need a bec for this servo to run at full power. Seems like it use to run my stronger then it does now. I use to able to move rocks with this thing
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Old 03-19-2018, 01:28 PM   #20
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Default Re: Electronic Problems? You probably need an External BEC

Do you have a crawler? Is your servo more than 125 ounce inches? The answer is that yes, you need an external BEC. Your servo might also be giving out too. Or you might be slowly destroying the internal BEC on your MMP. Unless you are running an ESC like the mamba X with a HUGE internal bec or running the servo direct from the battery, the answer is always yes.
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