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Unread 24-03-2011, 23:38
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Lightbulb Re: 2011 Lone Star Regional

Quote:
Originally Posted by Kevin Sevcik View Post
I'm calling BS on both sides here without some sort of verifiable data. First, the Jaguar isn't going to be terribly more "powerful" than the Victor. The FETS in the Jaguar have slightly lower on resistance, which means slightly lower power lost to heat, but it's pretty minimal and the Jag's current sense resistor probably makes the whole thing even.

Similarly, the Victor isn't going to have any quicker response than the Jaguar to a specified output voltage. They both use the same PWM rate, processing time is minimal, and I'm not going to get into whether the Jag's 15kHz chop rate would react any faster than the Victor's 120Hz chop, because you guys aren't capable of noticing that difference.

And both speed controllers are just as easy to drop metal shavings in. In case you didn't notice, the FETs on the Victor are right under that fan. The leads are exposed and just waiting for a chance aluminum shard to vaporize them.

There's only a few actual differences between the two:
1. The Victor is smaller, lighter, and more expensive.
2. The Jaguar has a more linear response curve. Meaning 20% input actually gives you 20% output. The Victors ramp up the output rather quicker than the input and then level off, so 20% input gives you something like 30% output. This may account for Paul's "quicker response".
3. The Jaguars have built in voltage rate control, which prevents you from rapidly switching between positive and negative outputs. The Grey Jaguar was likely to blow a FET driver under these conditions, which is apparently what gave the entire line a bad rep for reliability.
4. The Grey Jaguars had captive screws that were never meant to be fully removed. They left metal shavings inside the case if you DID force them to unscrew, which added to the number of failures. Which is rather more operator error than lack of robustness. Black Jaguars have fully removable screws.
5. The Jaguars have current and temperature limiting features which kick in to protect the speed controller from damage under high load conditions. The Victors will let you beat them till the breaker or the Victor blows.

And that's it until you get into the laundry list of features the Jag has that the Victor doesn't. So as far as I'm concerned the robustness of the Black Jaguar is still in the proving stage but looking good and there's little performance difference between the two aside from the linearity of the output. I think anything else is hearsay and confirmation bias unless someone's got some actual test data to back it up.

Based on the above information, I also believe it depends on the application of the device. It would be interesting to see if a team or a group of teams would test the JAGs and Victors under similar conditions and collect data to be posted on CD as a white paper for all to reference for future use. Let's not favor on device over another unless it can be backed up with data. This is how engineers determine which device should be use over another, not by individual gut feeling. This could cause issue as was seen in the past without data to back up claims of problems. Think about it.
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