BEC wiring and Glitches

[prioret]

Guys,
I have added a CC BEC to my clod setup as diagramed below. I'm getting some glitches on both throttle and steering. I have read through some other posts, but have not seen a dual battery setup. Am I doing this right? Is there a better way?


ClodWireing by prioret, on Flickr

[Trubble]

I guess the only questions I'd have would be...


2.4 radio?
What ESC?
Which BEC?
Did you program the BEC to output the proper voltage?
Did you take a voltage reading at your BEC's connection point and make sure it's not getting the voltage doubled? And/or can your BEC handle the input if the batts are for some reason hooked in series?

Check out the lower left image at -this page- (all the way at the bottom, left side) you may need to look at maybe transferring your connection point to the other battery's leads.

[SMR 510RR]

I would say that if your are not using a 2.4 radio that you are having interference issues.

Try getting the receiver as far away from the BEC and ESC as possible, that should help but you really should upgrade to 2.4 if you dont already have it.

[prioret]

Its not 2.4 its a futaba 3pm
The esc is a Traxxas EVX2
The BEC is the CC BEC.
I dont have a programmer so the BEC is putting out the default voltage, which is I believe 6V
The BEC is only getting voltage from one battery pack. even if it got both, it would be under 25V so I would be safe.
Before I had the BEC I didn't have any glitches, I have tried the BEC in multiple locations and it hasn't helped.
I have it wired the same way as the diagram you pointed out.
The glitches occur both at speed and stationary, and get worse if the radio gets with in a couple of feet of the truck. Because of this I don't believe its due to a voltage drop to the RX.
I was thinking of changing it so that the RX is powered by the ESC, and I could power the servos with the BEC.

Originally Posted by Trubble

I guess the only questions I'd have would be...


2.4 radio?
What ESC?
Which BEC?
Did you program the BEC to output the proper voltage?
Did you take a voltage reading at your BEC's connection point and make sure it's not getting the voltage doubled? And/or can your BEC handle the input if the batts are for some reason hooked in series?

Check out the lower left image at -this page- (all the way at the bottom, left side) you may need to look at maybe transferring your connection point to the other battery's leads.

[MRCCRAWLER1.9]

i believe the default BEC voltage is 4.8v not 6v.

BTW did you take out the red wire from the ESC side? i accidently left mine in, and it caused very bad glitching.

How does your car glitch? does it shut off momentarily then come back on?

[rmdesignworks]

Originally Posted by prioret

Its not 2.4 its a futaba 3pm
The esc is a Traxxas EVX2
The BEC is the CC BEC.
I dont have a programmer so the BEC is putting out the default voltage, which is I believe 6V
The BEC is only getting voltage from one battery pack. even if it got both, it would be under 25V so I would be safe.
Before I had the BEC I didn't have any glitches, I have tried the BEC in multiple locations and it hasn't helped.
I have it wired the same way as the diagram you pointed out.
The glitches occur both at speed and stationary, and get worse if the radio gets with in a couple of feet of the truck. Because of this I don't believe its due to a voltage drop to the RX.
I was thinking of changing it so that the RX is powered by the ESC, and I could power the servos with the BEC.

thats the best way...default voltage for a CCBEC is 5.1vdc...program the bec and run it direct to the servo/s and power the Rx with the ESC

[reden]

Test ferite rings on the power wires at the BEC and ESC's
Some BEC's comes standard with it.

I've got a simmilar setup and problem.
Everything works fine until I plug in the steering servo signal wire.
The RX then looses it's bind but without the bec or esc and RX on battery nothing happens.
Lets say it's some resonance in the wires.
Had less problems with same setup on 27MHz.

[Trubble]

Originally Posted by prioret

The BEC is only getting voltage from one battery pack. even if it got both, it would be under 25V so I would be safe.
I have it wired the same way as the diagram you pointed out.

If it's wired as the diagram on the bottom left, you're getting the voltage of both batteries. While I agree you'd still be 'safe' on your input voltage, notice in their chart that the amount of amperage you get by going with higher voltages does go down. Still, I would think even 5 amps should be enough to feed two servos and a receiver.

Originally Posted by prioret

The glitches occur both at speed and stationary, and get worse if the radio gets with in a couple of feet of the truck. Because of this I don't believe its due to a voltage drop to the RX.

Yeah, once you put this in, I don't know that I can hold the BEC under much scrutiny anymore. May need to look for power leads and/or motor wires running too close to the rx and/or antenna. Someone mentioned the ferrite rings, I notice on Castle's site the BEC Pro has them pictured. Might be onto something. Sorry I can't be of any more assistance, but if you find out how to fix it, we'd certainly appreciate hearing about it.

Originally Posted by prioret

I was thinking of changing it so that the RX is powered by the ESC, and I could power the servos with the BEC.

Okay, (I apologize for the tread hijack, sorry), I have a question on how you'd wire that up. Red & black from BEC to servo (or brown and orange, whichever), and white (yellow) (signal) to the reciver, got that much...... Does the black (or brown whichever) also need to go to the reciver to complete the signal circuit? (assumes all three wires from ESC are connected to the receiver)

[SMR 510RR]

Originally Posted by Trubble

Okay, (I apologize for the tread hijack, sorry), I have a question on how you'd wire that up. Red & black from BEC to servo (or brown and orange, whichever), and white (yellow) (signal) to the reciver, got that much...... Does the black (or brown whichever) also need to go to the reciver to complete the signal circuit? (assumes all three wires from ESC are connected to the receiver)

No, all you need is the power wires from the BEC (red and black) to the servo and signal wire from the servo to the receiver. You can ditch everything else.

Its definitely the best way to wire a BEC for a crawler.

[Trubble]

Okay, thank you.

[Charlie-III]

Originally Posted by SMR 510RR

No, all you need is the power wires from the BEC (red and black) to the servo and signal wire from the servo to the receiver. You can ditch everything else.

Its definitely the best way to wire a BEC for a crawler.

Side note: some radios don't like this setup (our Futaba 4PL & 3PM-x don't mind), they really want the BEC red to the servo, BEC black to servo & RX, servo signal (yellow or white) to RX. The black is the ground and is needed in some situations.

I just run the BEC red & black direct to the servo.

[Rok Krawl]

I had same glitching issues with my setup. My CC BEC has 2 outputs. Each were hooked to a servo via a y-harness. I had only the signal wire going to the RX. After having issues I was told to try to also include the ground wire to the RX. This took care of my problems. Radio sys I use is Airtronics m11 FM.

I myself didnt have any issues until I hooked up the BEC. But try ground wire to the RX. My BEC is mounted on top of battery tray. ESC and RX mounted behind battery tray. Servo rear motor wires run right by RX and I do not have any glitching issues. And I can drive it 100+ feet away and still have full control with no problems.

I too thought with the extra electronics I had more radio static and interference with added BEC and myself tried to move components around to get the cleanest signal.

[JeremyH]

Originally Posted by Rok Krawl

After having issues I was told to try to also include the ground wire to the RX. This took care of my problems. Radio sys I use is Airtronics m11 FM.

That is very strange. I havent had any issues with my setup using the y harness. Maybe those Airtronics RXs are more sensitive to interference than what I am using...

[Charlie-III]

Originally Posted by JeremyH

That is very strange. I havent had any issues with my setup using the y harness. Maybe those Airtronics RXs are more sensitive to interference than what I am using...

Like I stated in post 11, some radios don't like a 2 wire direct to the servo, they want a ground to the RX as well.

Seems like Futaba doesn't care, others are picky. It's not a good/bad thing, just how they work.

[prioret]

Originally Posted by Charlie-III

Like I stated in post 11, some radios don't like a 2 wire direct to the servo, they want a ground to the RX as well.

Seems like Futaba doesn't care, others are picky. It's not a good/bad thing, just how they work.

My guess is that is to the rx having some kind of ground loop through the esc. Meaning the there was a voltage potnential between the bec ground and the esc ground to the rx. One would assume that the bec ground would be directly to the battery negitive wire and the esc would have its ground plane to the neg battery wire too. It is possible though that the ground to the rx from the esc is on a seperate filtered ground plane meant to reject noise from the esc itself.

If that were the case then the servos would be at a different ground thne the rx, so you could have a bias on the signal wire and possible clip some of the pulses.

[prioret]

Yep that fixed it. The RX is now powered by the ESC, and the servos by the BEC.

Originally Posted by rmdesignworks

thats the best way...default voltage for a CCBEC is 5.1vdc...program the bec and run it direct to the servo/s and power the Rx with the ESC

[Charlie-III]

Originally Posted by prioret

Yep that fixed it. The RX is now powered by the ESC, and the servos by the BEC.

Great! Glad it worked & thanks for closing this out for the next guy.