What will it take to overheat A victor?

[DonRotolo]

Fluffy,

I agree with the advice above, and you'd be well served to heed it.

Thinking a bit outside the box, this sounds to me like a perfect pre-season experiment: What, exactly, does it take to overhat a victor? And, does it go into shutdown or thermal liquidity (i.e., melt) when it passes the safe point?

Start with some research with the IFI folks, I am sure they'll take your phone call and shower you with data. Next, take a Victor, and associated items to simulate various current loads, along with an accurate temperature probe (like a thermocouple). Measure the temperature at steady-state under variuos loads and both with and without the fan, and also in different kinds of restricted areas (a small box, for example).

Then, the important part: Publish your findings in a white paper for the rest of us to see. In this way, not only do you really learn the answer to your question, even the part about "it depends", but so do all of us...

Don

[popo308]

Originally Posted by Al Skierkiewicz

Only the 885 is rated for 48 volts and this model is not available for use on FIRST robots.

Ok, sorry i was thinking of the wrong model. I knew one of them was rated at 48 volts.

Originally Posted by Al Skierkiewicz

Not specifically called out as such but... IFI lists the fan as an integral part of the Victor and as such, electrical parts provided in the KOP may not be modified.

I would have to agree with Al hear. It does not just come out and say it but it is implied. I highly doubt you would make it through an inspection with no victor fan on.

All in all its not needed unless there is a lot of current draw i suppose. But FIRST does want them on. Its better to be safe then sorry with victors anyways considering they aren't exactly "cheap".

[eshteyn]

Personally i have taken off the cooling fan and run 2 cim motors at 40 amps each off of the victor. The victor ran for about 15 minutes before the heat overwhelmed it.

[popo308]

Originally Posted by eshteyn

Personally i have taken off the cooling fan and run 2 cim motors at 40 amps each off of the victor. The victor ran for about 15 minutes before the heat overwhelmed it.

Were the sims stalling at all by chance??
40amps is quite a load

[Richard Wallace]

Originally Posted by popo308

Were the sims stalling at all by chance??
40amps is quite a load

40A is about 50% above the specified normal load for a CIM motor, per its data sheet. CIM motors can operate at 40A for quite a while before they will overheat -- much longer than a 2 minute FRC match. Stall current for a CIM is much higher, around 130A.

[Mike Betts]

To continue Richard's point, peak power on a CIM is at almost 70A. Most "competitive" teams will design so that the 70A point is reached several time in a match (maximum acceleration, et cetera).

[popo308]

On our 06' bot we had a basic 2 sim drive with omni wheels in the front and they went not much more than 6-8 min of constant driving before they were stalling out because of heat. In a actual match this wasn't an issue but in finals or practice they would overheat and cut out.

Are 07' bot had a 4 cim swerve drive and when we were in are low gear and were in a pushing match with another team the motors would sometimes stall out which was causing them to heat up very fast. At ARC we were very lucky that we got enough time between finals that they could cool down.