Due to an oversight while doing some initial wiring, we accidentally hooked a Victor up red to black and vice versa. From all that I’ve heard and seen, it’s now fried, right?
So a mentor was there, and he mentioned they could be repaired. Now, I’m just wondering. How would one go about repairing these? Is it worth the effort, or should we just buy another?
Have you tested the victor to make sure it’s “fried”? You might have gotten off easy.
Either way I wouldn’t use a repaired victor on the robot; there’s too much potential for something to go wrong.
if you find out how to repair a BBQ’d victor that smells like burnt **** let me know, theres a pile of them building up. most of the time you will have not had any permanent damage because the breaker that you hopefully hooked up will have popped almost instantly and remain clicking until you disconnect power. if you didn’t have a breaker, then lots of people will be unhappy with you for blowing out a relatively expensive component by not taking the time to follow the rules as far as electrical wiring on the robot goes. also a thing with the victors, if you have a screw that is too long holding the wire on, and it touches the bottom, something similar will happen and it will short.
Not necessarily. We did that a couple of years ago, and all it did was pull enough current to continually trip the 40A breaker protecting it. After we realized the mistake and corrected it, the Victor worked fine. I don’t know the internal circuitry well enough to be sure, but I suspect there’s a diode across the power pins to prevent a backwards connection from destroying the Victor.
So a mentor was there, and he mentioned they could be repaired. Now, I’m just wondering. How would one go about repairing these? Is it worth the effort, or should we just buy another?
The usual repair for a “fried” Victor is simply to replace the FETs. It’s definitely worth the effort – you save a hundred dollars doing it that way instead of buying a new one.
Repaired circuits are excellent for experiments and training new electrical people. Also, one fried CIM that we have was more useful as a model for welding than it had ever been as a working motor. And always have someone else check your circuit before you add in the power element. Remember, a bad circuit still won’t fry anything if there is no electricity with which to fry!
We had it running through the Maxi breaker, and it remained clicking.
Our mentor said the wires’ reversal should cause it to be fried, so we simply replaced it and didn’t check. We still have it, so when I get a chance, I think I’ll see if it may still work.
There’s no chance that if it is broken the motor or robot controller could be damaged, is there?
And yeah, we checked the circuit, but we’ll most definitely be checking them more thoroughly now.
the clicking is what I was talking about in my earlier post. that clicking noise is the snap-action breaker overheating and cutting power. which is a good thing for it to do. if it did that and you didn’t see the magic smoke escape from the controller, you are probably fine. also, the fans don’t like being reversed for some reason, so check to make sure its spinning after you reconnect it.
also, there isn’t any way I can think of right now that would damage any component other than the speed controller itself.
the thing that blows up the speed controllers most is when you drill into the robot and pieces of metal fall into the speed controller. it often makes an audible crackling sound and almost always results in the speed controller failing catastrophically, and letting out the magic smoke.
:rolleyes: remember, the speed controller operates on magic smoke and if you let it out, it wont go back in and you have to buy a new one. :rolleyes:
I belive it would just be easyer to replace the victor, if its truly “fried” then i would think best not to cry over spilt milk but if you can repair it, all the power to ya!
That’s a $120 glass of milk! If anyone manages to repair these then please let me know, I have a pile of them that we burned out from hooking up the PWM cables backwards. (We didn’t read the victor manual until the start of our third year, which suddenly explained why these things kept burning out)
OK,
The Victors do not have much in the way of reverse voltage protection. There are a variety of things that can go bad when you don’t watch the wiring. To mangle a “This Old House” phrase check twice, power once. Of the conponents that can go bad we start with the power input. Just like the IR board this year, a 5 volt regulator does exist here as well. There also is a rather large electrolytic cap which you can see hiding in the center of the FETs under the fan. Finally, all the FETS have a diode across them that will likely be forward biased with a voltage reversal. Now it is entirely possible that you got lucky and none of these things has died. You need to check operation to be sure. If it all works then great. Just be advised that the parts have already been stressed. If I needed to use said device, I would be more inclined to use it on a low current motor than a drive motor. Some teams have found that Victor failures usually are just FET problems and have had some success with replacing them. If you Victor is truly dead, get in touch with IFI, they might just repair it for minimal cost. There is a warning in the 884 Victor manual,
WARNING: BEFORE APPLYING POWER:
We’ll hook it up and see if it still works on Thursday. If not, I’ll see if I can troubleshoot it using Al’s suggestions. The 40 amp breaker was clicking continuously for at least a couple of minutes, so there was a lot of current going through something inside. I suspect the 5v regulator is toast. The electrolytic cap had not popped as far as I could tell without taking the fan off, but the top looked good and there was none of the usual smell.
I did recommend not turning the robot on until someone had double checked the wiring…
And shouldn’t you be studying for finals?
Yeah, yeah, finals.
Gibby and I checked em over, but it seems that somehow got overlooked by us both. Anyway, it doesn’t hurt to try it out again. If it doesn’t work, we’re back where we thought, if it does work, so much the better.
Here is my experience in applying reverse voltage to a Victor. It happened in about 2004 so they were Victor 883s not 884s.
A student was building a small test electrical panel for a drive prototype. He wired all 4 Victors backwards and applied power to it before asking any one to check his work. It obviously didn’t work on his power on test, so he turned it off and sought help. We fixed the problem and tested the board again. Everything worked for a few seconds then one FETs in one of the Victor 833s blew out. The rest of the Victor’s were fine.
We disassembled the broken Victor and noticed damage components other than the FET so we didnt try to repair the Victor. We desoldered the broken FET and screwed it to our workbench as a reminder to check your work.
That is my experience, take from it what you will. Only 1 of the 4 Victor 883 failed so there is a chance your Victor still works, but I wouldn’t trust it.