We tested our drive train today, the victor on one side blew immediately. We then tried blowing out our electronics and replaced the victor. Again as soon as power was sent through the victor it blew (nothing happened when power was on but the bot was disabled). Has anyone had this problem before or do you have ideas on what to check for or what could cause this? We have already checked to see if any power was running through the chassis.
Thanks
Are you talking magic smoke time or did the breaker just trip?
The Transistors blew, magic smoke and all. The breaker never tripped.
How are the Victors wired to the motors and to power? Which terminals are connected to what? Sometimes people don’t notice or understand the markings on the Victors and wire the wrong end to power, which causes things like this to happen.
Yes, Power and Ground are going to V+ and V- and the motor is connected to M+ and M-
Every so often my Fuse keeps popping even though the board is wired right. In years past I used the 20 amp auto reset breaker where the fuse is supposed to go. Not sure if it is legal this year but once again I’ve done it in years past
Is there any way you could get a picture?
I’d also check for a short between your M+ and M- leads. A problem on that side might not affect the robot while the Victor was in neutral.
What do you want the picture of? I know they were wired properly, they were identical to the other 3 that worked fine. We have multiple veterans who looked at it and we know that it is wired properly.
James
I believe you are confusing spikes and victors.
I know this is repetitive and somewhat rude, but what you describe (i.e. multiple failures of the same Victor) tell the tale of the primary wiring backwards. It may be correct at the Victor end and switched at the breaker panel and terminal block but this is classic failure mode for power lead reversal. Sorry, justs trying to help.
If it were wired properly, it wouldn’t be frying Victors repeatedly. Something is almost certainly not identical to the ones that work, and it’s obviously something…um…unobvious.
Try powering up the robot with no Victor installed, and measuring the voltage on the wires that you intend to connect to the V+ and V- terminals. Also test the motor that you intend to connect to the M+ and M- terminals.
The motors all seemed to have the same resistance between them, so there isn’t a short in the motors. We tested each motor individually on an older speed controller. They both worked going through a 20 AMP breaker (just in case there was a problem with too much current). We then wired it back up the same we had it (through the 40 AMPs) and its all working fine now. Although we’re still not positive what the problem was.
Thanks for everyones help.
Patrick, I don’t call it fixed until I have a “smoking gun”. Something was wrong, even if it was a broken Victor that was replaced with a broken Victor. Keep looking. Murphy’s law says it will go bad again on the final match on Einstein.
I never said it was fixed, just that it seems to be working fine now. We’re still going to investigate the problem, but we had to leave the shop today. We’re going to contact IFI and see if its possible it was a speed controller. We’re also going to check every crimp and connection, make sure that nothing could have shorted, etc.
We haven’t given up yet…
We agreed, the reason the circuit was reassembled is we were trying to reconstruct the problem in the lab(rather than when driving). We removed all of our drive electronics and then tested them one thing at a time. We checked for shorts to ground as well as abnormal resistances in motors, and victors. We then added our components together until the whole control system was rebuilt. We are hoping the issue was just with the victors (as Pat said we are contacting IFI). We will update if we find anything else.
I agree with Al Skierkiewicz, if there is a problem it should be addressed replacing the victor would be a good first start. If the problem occurs then the problem is with the circuit. One possibility could be a short in the Victor do to metal shavings. As a habit I use a can of air over the victors every time I drill or cut a piece of the robot when the board is mounted. That could have happened and yes I’m sorry I was confused between the spike and victor. Last night was a long night at the Robot Factory
Sorry I didn’t get back to you sooner, we were building a robot 
I just think that it’s helpful to take a few pictures of the wiring/electronics board so we can “look over your shoulder”. It is very difficult to diagnose someone else’s problems with only a short description of the situation. A picture is worth a thousand words…it may reassure us that you do indeed have everything wired up properly, or we may notice something that you didn’t.
Sounds like you may have fixed the problem, even if you don’t know what was wrong…I hope it was just some simple thing that you overlooked the first time.
Well it seems that it was a bad CIM motor. It happened once more a week ago. We changed out the motor and it has been fine since then. Most likely a short that occured only in certain positions.