Oh Dear! I Just Fried My Whole Truck!!!
 

This really really really really really really really really vacums:mad:1:035:! I was trying to wire in a fan so that if I turned on the main switch, the fan would turn on too. The fan would be powered from the main batteries. I also wanted another switch that would switch the fan from being powered from one 7-cell battery to both 7-cell batteries. Well, I wired everything up like in the pic.
http://img487.imageshack.us/img487/9...nmodvm8.th.png
When I turned switch 2 on, the fan turned on, my shifting servo went beserk and stripped itself, smoke came up from somewhere, I smelled that horrible smell of burning silicon, whether it be a circuit board or wire insulation or both, and a steady stream of curses issued from my mouth. That was yesterday. Today, I wanted to try and run my truck. I put everthing back together, only with no fan in the equation. Just all the servos, esc, and RX pack plugged in to the reciever. I turned on my transmitter, then the reciever. Nothing happened. The servos didn't even move like they do if you turn the reciever on without the transmitter on. I cursed. I checked the Rx pack. It read a little over 6v. My 7-cell GP3300s were freshly charged. I tried switching to a different Traxxas 3-channel reciever. Nothing. Once again, I cursed. I untwisted the programming wires(same as removing red programing jumper) to try and program the 9920. I turned it on again and plugged the batts in. Nothing. The ESC didn't even make the motor beep for programing:012:. I usually have a very clean mouth and don't curse or swear or cuss or anything like that. Today is different. Very different. I went and got out my EVX. I plugged a battery into it's BEC side and the little LED lit up. I plugged it into the channel 2 port on the new reciever. Then I plugged the steering servo from my Villain into channel one. I turned on the transmitter and the servo budged. I turned the steering wheel right. The servo turned right. Then I tried plugging in the steering servo in my E-Maxx in place of the boat's servo. Nothing. Didn't budge, didn't respond:012:. Right about now, I'm bawling my eyes out because I know what's comming. I plug the EVX into the battery slot on the new reciever and plug the shifting servo into channel 3. Nothing:012:. I take the plunge and plug my poor little 9920 into channel 2 on the new reciever with the EVX providing BEC in the battery port. I turned on the transmitter and squeezed the throttle. NOTHING!!!!!!!!!!!!!!!!!!!!!:012::012::012:

This is very, very, very, very, very, very bad. I can't afford another 9920, and even if I could, my parents wouldn't let me spend that much money. I have to save half of what I make, and right now I have about $10 of usable money. I'd have to make $360 to buy another one. That would take about a year or two.
My only hope is that one of you might come up with something I overlooked, or if my 9920 is under warrenty or that Mike has some way he could fix it.

Thank you for any effort you put into this,
Brijar...:012:

Ok, According to the diagram above.. It looks like you have fried your Reciever, not your ESC.

Ofcourse, since the reciever is attached to the ESC, there is a possibility for damage to the ESC.... But I would suggest replacing the RECIEVER first, as I believe what happened is that one of your 8.4v packs sent 8.4v through the reciever power circuit and to all of the attached servos...

-J

I don't like the looks of your wiring diagram. It looks almost as if you shorted some of your stuff out. I not sure what may have fried and what may not have. Is the receiver letting power go thru to other stuff. did you try internal bec on the esc to see if that helped. I would try it on one 8.4 pack or 12 cells.

That's what I thought. It may have sent the whole 16 volts through the system though. 8.4 is not that much more than the 6 it usually gets, but 16 will definately blow it.
Also, if the voltage was sent to the reciever and blew it, then went on to the servos, it would most likely have gone to the ESC as well:012:.
As I stated in my first post, I did try a different reciever. Same brand and model, but it was a different receiver. I know that that receiver works too, because it opperates the steering servo in my boat when my EVX is powering it. I also tried using different crystals too.
It seems to me that I have had rather bad luck lately. I just recieved a $70 order from RC-Monster and Tower. I had also just gotten my front CVDs from Ebay. I just found out my now fried steering servo just went out of warrenty:dft002:. I have almost bullet-proofed my drive line with full CVDs, Steel Idler in 1st, Aluminum diff cup in the rear, and 4-screw differential cases. Just when I get it all together, something else breaks:007::035:.
Why me:025:...

Brijar...



Edit: Coolhand, the reciever won't do anything. None of the channels work, no matter what I do. But I'm more worried about the 9920. I've tried using a new and working reciever on it with external BEC supplied from a working EVX, and it won't do anything. I'm going to go try the ESC again with the new Rx and a 6v reciever pack.

Well the esc may be fixed under warranty. Hard to say. You can strap the shifting to one gear and play. As for the steering. You may have to go back to a stock servo if you have it to play. Email mike with the like to this thread and see what he says. I hope you the best.

Thanks a lot. I'll see if I can E-Mail Mike. I probably have a spare servo somewhere that I could use for shifting, and I can take my 2055 out of my boat and use it for steering.

Thanx for the quick replies,
Brijar...

Sounds like the esc is holding up the run now. I would try the internal bec to see. I would think you could do much else to it. :D I would not have it hooked to nothing when plug it up for the first time.

I just tried the internal BEC, and it works. I used a jumper on the spare main power plug, used one 8.4v battery and put the little black jumper back on the two prongs farthest toward the center of the ESC. I plugged it to the steering servo of my boat, and it works. I removed the Rx pack from the reciever and only had the ESC and the servo plugged into the receiver. The servo moved, but the ESC wouldn't do anything.

Brijar!!!

my suggestion would be to contact Mike or even BK, I know I had my 1895 Micro replaced for $150.00 wich is way below hte $425.00 it cost me new, and it was 4 yrs old.....and I fried it by sending 123 amps thru it, and htey even upgraded it for me to a 2095....just a thought...

The wiring diagram is perplexing. I don't know how the wires are connected on Switch #1, but it's very possible that you shorted out the battery through the switch. I'm curious why there's a wire going from one of the main batteries' positive wire to the positive wire of the receiver.

I would make sure it's wired correctly and try it again. I don't think the switches are a very good idea, they might not even hold up to the current. With the fans and ubec in there the wiring seems pretty hairy to me as it is, no need to make it even more complicated!

I've had escs that worked ok with jumpers and adapters on the battery, but on my 9920 I had to wire it up directly and use 2 batteries all the time, otherwise the speed control part didn't work right, one time I even smoked it! It still works now (knock on wood), so if your steering/bec works maybe it's still ok.

Try it with no fan or ubec at first, and make sure your solder joints are nice and solid. If it works, then you can add in the fan and ubec and sigh relief!

Good luck ~ I've once burnt 3 escs, 2 motors, and a set of lipos in one month, I feel your pain!!

Its certainly your wiring. I'll try and make a diagram if you still want a similar setup...Given the ESC is still ok.

This is what my switches look like. Switch one has one wire connected to both center terminals going up, one wire connected to both left terminals going down and one wire connected to both right terminals also going down.
Switch two has a positive wire from the battery connected to the left center terminal and a negative wire from the battery connected to the right center terminal. Switch two also has a positive receiver wire connected to the left side of the left terminal and a negative reciever wire connected to the right side of the left terminal. Here's a revised picture:
http://img96.imageshack.us/img96/4271/fanmodsd9.th.png
There is a bigger version of switch two on the right side.
Originally, I just connected the positive fan wire to the positive battery lead of the ESC. Then I put the negative fan wire to the yellow bridge wire. But then the fan would run when I had one battery plugged in. I was just too lazy to simply unplug the batteries.

If I make it out of this alive, I'm simply going to run the system without a fan and just change my gearing if it runs too hot. I'm trying really hard to get my parent(s) to help me E-Mail Mike. I'm also going to see if Tower will give me a couple of months extra on the warrenty of my steering servo, as I have spent around $1220:dft002::eek::confused: on them alone:013:.

I still can't get anything to work. I stuck an old motor and esc in my Rustler and took it for a quick spin, just to take my mind off things. I really don't like the look in my parents' face when I told them how much this costs:013:. If I can't get the ESC fixed for really cheap, like less than $50, then I might have to give up brushless:012:. I WON'T LET THE BRUSHED PEOPLE TAKE ME ALIVE!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!:035:

Brijar...

Just took another look at your NEW diagram.

Don't do it that way either, you'll blow up even more components. I'd suggest you let someone figure the wiring diagram out for you, because as of now, it's not even close. (No offense)

Someone with a little bit more electronics experience might be able to get this going the way you want it to.

First of all, what is the fans rated voltage? Are you trying to achieve dual speed with switch 1?

Switch 2 is hooked up very oddly. It's not obvious, but if switch 1 is in the left position and switch 2 in the left position, you are sending 16.8v to the fan, and are sending that same 16.8v to the Rx and Rx pack. Very bad. You can't forget that the throttle lead of the ESC has a ground in it and hooks to the Rx creating a common ground path through the Rx.

I will draw up a new diagram for you if you like. But first, I'll need to know the answer to my first question.

I don't completely understand the purpose of using switches. You can use a 12v regulator if the fan is a 12v fan, or if it's a 5v fan you just plug it into the receiver. Then you can use a switch on the receiver battery.

I think what he is trying to do is send either 16.8v or 8.4v to the fan depending on the switch position. I agree; a regulator would be in order, but makes the circuit a little more complex to achieve a dual voltage. 16.8v is just too much for a 12v fan if that is what he has.

Personally, I would just get a 6v fan and hook it to the Rx pack. If he still wants a slower speed, I'd put a few diodes in series to bring the voltage down. It's crude, but very simple and easy to wire up.

Heres a diagram. You can run your RX voltage or your total pack voltage (or 8.4 if you want. It all depends on the fan voltage). Switch 2 is optional, switch 1MUST be OFF if you turn 3 on and 3 MUST be off if you turn 1 on.

Why have switch one if it has to be off? The connection point right there isn't necessary (RX to fan).

HOW the switches are wired in, not correct. And i think someone here(can't read back that far) said they may not be able to handle the current anyway. So, with that said, REMOVE the switches completely, run your fan from your rx so you know it's only getting 6V, if you fry your fan when it's hooked to your batteries, it will create a dead circuit sort of speak. And, you may already know this, but your servo is GONE by now, and it so being, will also create problems.Run your fan with a Y connector with the batt, remove the switches completely, i think that's tha main problem or was...most importantly, when you rewire it up, draw it out first and then do it, TAKE YOUR TIME, you'll get it. Wire one thing at a time!

PS. I just got my 12020 wired tonight...IT WAS A PAIN IN THE ARS!!! TOO MANY WIRES!

Yup, like newuser said, I would just plug it into the REC....However, if you want to do it that way, theres my diagram above...

Metalman, who are you refering to?? I had a other diagram on there but had a problem with the wiring :p....

Hey Squee, not that it matters, but i notice you always do this. And I'm only saying this because someone asked me if my name was a typo, but it is suppose to be new-e-user! lol, you always put newuser! it's ok, i'll take it as a nickname!

Ooops! sorry :p....Don't feel bad...Serum always mixes up Ncazbnmaster's letters....On purpose though :p.

I don't feel bad, i thought it was funny actually, and to be honest, i see more than just you do it! It's like there is no e half the time! But, i am new sooo.....And the name i'm not even going there it's so long, i can see why with that in a sense....i can't even roll it off my damn tongue! NBo offense dude, in fact, what does it mean?

Anyways, back to business.....if i were him, i would remove the switches, check one piece at a time, and install with care...

Here is a different diagram using two switches and it's pretty simple. The diode pack is just 6 diodes in series to drop about 4v so the fan will be safer. The switches only need to handle no more than 3-5A, so they should be fine - they aren't carrying high currents.

BTW: Sorry for the crude drawing.

Good job BrianG - but squee has you beat in the area of artistic ways! Great diagram though, very simple...I think i'll print it! But you did forget wires to the rx...but i suppose you really don't need those cuz they are self expanitory

NewEuser, his name is actually nbcaznmaster. Which nbc is his schoo, and azn for Asian, and master for well, master..... Oh, and thanks for the compliment...I kinda like paint :p.

Yeah, I didn't want to spend much time - at least the idea comes through. :)

I didn't add in the other Rx wires because they weren't in the orginal drawing and I wanted to keep the power path clear.

BTW: The diodes can be generic 1N4001/1N4002 components available at RadioShack. 1A should be PLENTY for a fan.

How do you solder them would be good info to pass. i would but never used them, but may help him too. And thanks Squee for the E!:018:

I always wondered what that meant. I just thought he jammed on a bunch of keys and then added "master" to the end when creating his username! :005:

See! That's why your version is pretty; using that complex Paint program! I used crappy Paint Shop Pro. :dft012:

Diodes look like this. See how one end has a little silver band? That's the cathode, or negative side. You just hook them up like you would batteries; end to end.

+- +- +- +- +- +- +-

The power input would come in on the left and the load hooks to the right. Each one drops about .7v. There are other better ways to drop some voltage, but this is easiest IMO. Another simple way is to use a resistor, but the amount of voltage dropped depends on the current draw of the fan.

Cool, that shold help him. Never had the need. So do you use them really when your running too many Volts?

Actually, diodes are intended to be used like a one-way valve; they only allow current to flow in one direction. However, they drop .7v each, and I use that fact to reduce the voltage. Only do this when the load current is small (<= 1A).

There are other better ways to drop voltage, but they are generally more complex and not as simple to wire up for those who have no electronics knowledge.

Hey NEWUSER.........hows the 12020 coming.......also the fan info was good guys.....I hope you get it fixed man.....

Thanks for all the fan info guys, but I have decided to just not use a fan if I get a new controller. I was trying to keep this whole fan deal cheap and just use a 12v fan I had lying around. What I should have done was asked if a 12v fan could take 16.8v. I ended up know that in the end.
I haven't e-mailed Mike yet, but it's Saturday here, so there is a good chance I will get to.

LOL, I started this thread to find out if there is any hope of getting my controller fixed, but you guys took off about how to wire a fan:D. Thanks for the info anyway. I will most likely ask you people before I go and try to wire something custom/different/weird/stupid up:007:.

Thanx a lot,
Brijar!!!

Sure a 12 volt fan can take 16,8 volt, it can take even more if you want to. It's just not going to live as long as normal.

I run a small 5 volt fan off of a six cell pack without any problem. Also no weird switches, just on 1 side of the dean plug(both + and -)

Sorry about your loss there, really suck's to loose every bit of electronic's in just a few second's.

Yup, its not that the fan can't take the voltage, but the fact that you sent 16.8 volts to the reciever as well as possible grounded out the ESC.

And sent 16.8v to the receiver pack...

Eh, I still don't like that diagram, at least I would test it first beofre I put it with the rest of the electronics. What I don't see is a resistor in line with the fan. The fan and diodes should have some small resistance, but really it looks like you will just short out the fan/batts again. Maybe fans don't need R's? Not sure, but I wouldn't bet my esc on it.

What I would do it just tap a line right off the ESC where the input voltages go in (solder on top of the batt wire connection) and run it to the fan with a resistor (and diodes if needed.)

Here is a 12V 40mm fan It needs 120ma. So for 16.8V: (R=V/I) ~16.8V/0.12A=140 ohm. (150 ohm closest iirc.) If you use diodes to drop voltage you will need a lower R.

Note also that P=I^2*R. P=(.12^2)(150)=2.16W. You need at least that high-rated a resistor, or at least a combo of smaller resistors to do it. Ratshack has mini-resistors upto .5W, then bigger sandbar resistors.

If you do it this way, you don't need a switch to the fan, or long wires going everywhere. It will only turn on when esc is plugged in. You may switch your RX, but don't leave batts plugged in anyway.

Useful link with calcs

I would first do this with just the batts and fan. If you don't blow anything up, then integrate w/ $$$ escs. Or just get a 5v fan and a y-cable and tap off the rx and leave it easy...

G/L

I would just get this and a y-cable into a RX. Easy, no fires, crying, etc..