Castle 10amp BEC FIRE

[johnnyh66]

Halfway through yesterdays comp, I noticed a slight drop in power and then smoke!
I unplugged everything asap...
I need to sit down with this stuff tonight and trouble shoot to see what is burnt up and what works but after trying an off course repair yesterday I think I lost:
1. Castle 10amp BEC for front servo, it causght on fire.
2. Castle 10amp BEC for rear servo, was packaged next to the one that caught on fire. Some of the shrink wrap is scorched but didn't look melted but it does not seem to be working.
3. Savox SC-1256TG (277oz @ 6v)was front servo. This servo was connected to the BEC that caught fire. It does not seem to be working.

I was running:
BR-XL
HH 14T Puller
6s (x2 3s)
Futuba 4PL
Castle 10amp BEC for front servo (stock setting)
CreationFab rx bypass adaptor
Savox SC-1256TG (277oz @ 6v)
Castle 10amp BEC for rear servo (stock setting)
CreationFab rx bypass adaptor
Savox SC-0251 (222oz @ 6v)

Anyone know what I did wrong... or just a faulty CC BEC?

My burned up BEC



the harness I made so I didn't have to cut up all the wires:


The diagram I followed:


WarTrader's BEC harness that I used as a guide for my harness:


the rx bypass from CreationFab


A demo of what happened when I tried to stuff 6s through the CC BEC:

[JohnRobHolmes]

Both were set to 5.1v? Did you double check the outputs with a voltmeter?

We may have to start installing blocking diodes, I have a feeling one BEC may have been pumping current into the other.

[johnnyh66]

No, I didn't check with a voltmeter... I assumed they were set to factory default.

[Charlie-III]

Originally Posted by JohnRobHolmes

Both were set to 5.1v? Did you double check the outputs with a voltmeter?

We may have to start installing blocking diodes, I have a feeling one BEC may have been pumping current into the other.

How?
Sounds like they had a common power input, but separate servos to go to, not sure how one would pump the other?

J66, sucks to hear. Those are the newer ones with the large cap in them, they seem to be a lot better than the older version.

[johnnyh66]

Originally Posted by Charlie-III

How?
Sounds like they had a common power input, but separate servos to go to, not sure how one would pump the other?

that's what I thought... you can see in the pic of my harness they share the same powersource and you are right Charlie, they then go off to seperate servos.

Originally Posted by Charlie-III

J66, sucks to hear. Those are the newer ones with the large cap in them, they seem to be a lot better than the older version.

You ain't kidding!
I was finally going to buy a good soldering station but now it looks like I have to buy a new servo and BEC's...

What do you guys think about the 20amp BEC Pro to power 2 servos?

[JohnRobHolmes]

it is safer to use one BEC pro than two smaller units.

If the voltage of one unit was slightly off the other (component variance, different resistance solder joints) it would make the higher voltage unit feed some current to the lower voltage unit, particularly as the load got higher. Unless I'm missing where they were electrically isolated. Probably just me missing that part. Both servos were powered independently?

[SMR 510RR]

Originally Posted by JohnRobHolmes

it is safer to use one BEC pro than two smaller units.

If the voltage of one unit was slightly off the other (component variance, different resistance solder joints) it would make the higher voltage unit feed some current to the lower voltage unit, particularly as the load got higher. Unless I'm missing where they were electrically isolated. Probably just me missing that part. Both servos were powered independently?

Yea sounds like he had each of the BEC's going directly to one servo while bypassing the RX and everything else.

[johnnyh66]

Originally Posted by JohnRobHolmes

Both servos were powered independently?

I'm pretty new to this stuff but I think so...
I had one power source going into 2 BEC's.
Each BEC was plugged into the rx bypass for it's Servo
Each Servo was plugged into the rx bypass for it's BEC

So, doesn't that mean the each servo was powered independently through the the rx bypass/bec?


ok, so the CC BEC Pro should handle both servos without a problem?
I was thinking about getting that one too... wish I would have.

[johnnyh66]

Originally Posted by SMR 510RR

Yea sounds like he had each of the BEC's going directly to one servo while bypassing the RX and everything else.

I had two bypass adapters... one for each bec/servo combo.

[JohnRobHolmes]

Yeah, with two adapters they were isolated. That would be decently safe with no need for blocking caps.

Give Castle a buzz if it is in warranty.

[johnnyh66]

They are both new, bought them a few weeks ago, first time run but I never filled out any warranty info or anything.
Can I show them Date of Purchase from an email receipt or something?

[JohnRobHolmes]

Yep. You may want to call or email for an RMA number.

[johnnyh66]

Castle said to send them both in
In the meantime, I now have a CC 20amp BEC on the way

[Jstall7543]

That sucks bro! Ive been there! What are the home electrical connectors your using? Not a good idea could have been a faulty connection. Solder and shrink wrap everything next time. That was a cool setup though! Could have been a bad bec, it does happen if the cap fails.

[SINister]

Does my fire need a BEC?

Sorry to here this man. I'm always afraid I'm gonna burn my truck to the ground when I first hook up a new setup. Hopefully cc will take care of you and get you backup and running.

[Jstall7543]

I'm always afraid I missed something myself. Yesterday I wired up two fxr esc's and a bec direct to the servo. I hate that felling right before I plug the battery in for the first time.