Problems with victor blowing

[JamesBrown]

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

[vhcook]

Are you talking magic smoke time or did the breaker just trip?

[JamesBrown]

Originally Posted by vhcook

Are you talking magic smoke time or did the breaker just trip?

The Transistors blew, magic smoke and all. The breaker never tripped.

[MrForbes]

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.

[JamesBrown]

Originally Posted by squirrel

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-

[EduardoVemny]

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

[MrForbes]

Is there any way you could get a picture?

[vhcook]

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.

[JamesBrown]

Originally Posted by squirrel

Is there any way you could get a picture?

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

[JamesBrown]

Originally Posted by EduardoVemny

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

I believe you are confusing spikes and victors.

[Al Skierkiewicz]

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.

[Alan Anderson]

Originally Posted by JamesBrown

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.

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.

[DarkJedi613]

Originally Posted by Alan Anderson

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.

[Al Skierkiewicz]

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.

[DarkJedi613]

Originally Posted by Al Skierkiewicz

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...