Drive with tallons

[bbradf44]

I wasn't sure if this should go here or under motors but here it goes. Tonight my team took inventory on all our parts in prep for kickoff and realized were almost out of usable jaguars. Usually we use jags for drive motors and victors for other motors. Online we noticed that tallons are cheaper than jags so is it a bad idea to use them for drivetrains?

[cgmv123]

Talons are an excellent choice for speed controllers. I'd argue they're better than Jaguars if you aren't using CAN.

[z_beeblebrox]

Their compactness, linearity and reliability make them some of the best drivetrain speed controllers. 10/10 would use again.

[MetalJacket]

Definitely agree with the above posts. We used talons for the first time last year (on just about every motor) and loved them, especially after having used all jags the previous year - the small footprint was amazing and they worked just as well as the jaguars.

[protoserge]

Look at the VEX Product Donation Voucher for this year. I believe there were some options for Jaguars in it. http://www.vexrobotics.com/vexpro/pdv-group.html

My opinion is to get Talons if you are not already invested in CAN with the Jags.

[bbradf44]

Thanks guys. I wasn't sure if they were only usable on lower power motors like window motors

[bbradf44]

Here's another question. Would talons also replace victors? Or just jags? I'm not sure of we use can I'll have to ask a programmer

[cgmv123]

Originally Posted by bbradf44

Here's another question. Would talons also replace victors? Or just jags? I'm not sure of we use can I'll have to ask a programmer

You can use Talons with every motor except Window motors. The switching frequency will disrupt the window motor's locking pins (just like the Jaguar's similar switching frequency also messes with the locking pins.)

[magnets]

Originally Posted by cgmv123

You can use Talons with every motor except Window motors. The switching frequency will disrupt the window motor's locking pins (just like the Jaguar's similar switching frequency also messes with the locking pins.)

I've heard this a bunch on CD, but I have yet to see it actually happen. We ran 3 window motors on jags last year on our practice bot, and 2 this year on victor 888's with no problem. We didn't remove the locking pins.

[MaxMax161]

Originally Posted by bbradf44

Here's another question. Would talons also replace victors? Or just jags? I'm not sure of we use can I'll have to ask a programmer

All three can replace all three (Except for window motors, I learned that today). The only thing you need to be aware of is that to change from jags/victors to tallons you need to change the initialization in your code as well otherwise the output will get doubled. (40% --> 80%, 70% --> 100%). Jags and victors can be swapped without code changes.

Here's the 1 paragraph summary of the different speed controllers. Talons and jags are more linear, meaning that when you say "Speed controller give me 20%" it gives you closer to 20% than a victor would. This is only at low speeds though, above about 40% the difference is negligible. Talons are sealed so no peaky metal shavings get in them and fry them, however they will fry if you hook them up backwards because they have no reverse current protection. (on the plus side you can charge your batteries like this!) Jags can do CAN which can be used for cool features.

[cgmv123]

Originally Posted by MaxMax161

however they will fry if you hook them up backwards because they have no reverse current protection.

Note that all 3 speed controllers lack reverse current protection.

[yash101]

Talons are sealed, so you can give a high five to the face with an arc-welder to metal dust and other debris that will murder your speed controllers so easily. Those small particles, though they seem harmless, will gather up, and work together to produce magic smoke! With the talons, you can say Bye-Bye to that!

Also, talons are passively cooled, because they have a shiny heat sink atop themselves.

Oh yeah. I forgot to mention that the talons are a much newer model, so the designers must have taken the flaws of the previous controllers and fix them in this. Otherwise, talons more-or-less behave like victors! I think that that is how you program them too!


---So the short answer is, Go for them! They will eradicate some of the team's headaches!

Quite some fluff in there^^

[Joe Ross]

Originally Posted by MaxMax161

All three can replace all three (Except for window motors, I learned that today). The only thing you need to be aware of is that to change from jags/victors to tallons you need to change the initialization in your code as well otherwise the output will get doubled. (40% --> 80%, 70% --> 100%). Jags and victors can be swapped without code changes.

I'm not sure what you're referring to by initialization. There are two relevant differences.

Both Talons and Jaguars are linear. If you calibrated a certain output with one, you should be able to swap to the other with no changes. Victor 888 are not quite as linear, and Victor 884 are not very linear. A value calibrated for a 884 or an 888 might need to change if you switched to another motor controller. See http://www.chiefdelphi.com/media/papers/2720

Both Victors and Talons use a hobby PWM range (1ms to 2ms). The Jaguar uses a larger range to gain more resolution. If you use a Jaguar, but program it with the Talon or Victor class, you will not get to full speed. Alternately, if you use a Talon or a Victor, but program it with the Jaguar class, you will only get partial range. There are less changes between the Talon and Victor classes, but you should always use the class that corresponds to the motor controller you are using. It should only be one line of code or one VI to switch.

[Chadfrom308]

We used talons for OCCRA and they worked without issue. We did put a fan on the drive motor talons for extra protection (although we didn't need them at all)

[yash101]

A little off topic, but how many MOSFETS are in parallel? #MOSFETS/4. Also, what are the rating for each MOSFET, not the Talon? I'm just wondering how much overload can the transistors take without breaking! If anyone has the info, it would be nice, and I could look at the datasheet if I had the model numbers.