We’re trying to fit an unusually large number of motor controllers into an unusually small space this year (as I imagine a lot of teams might be). We’re wondering if it’s allowed to leave the fans off of the speed controller and provide our own cooling by having a couple of side-mounted fans blowing across all the controllers.
Is it legal to remove the fans from Victors (either the old 884 or the new 888s)?
Is it legal to leave the fans off of the Talon speed controllers (since they already have a sizable heat sink)?
As the for the official ruling I am unsure. Many of our victor fan cables have ripped anyways that we took many fans off them, I believe we have passed inspection with the fans not even on (not certain though), We have I know passed inspection with none of our victor fans actually working. (I wish we got to FIRST Choice sooner, would have grabbed some of the talons.)
Remember even though the Talon user manual may say use is optional under 30 amps, it is not the FRC Game Manual and thus is not an official ruling for robot rules for 2013.
The only reference to cooling fans that I can find in the game rules is R65’s “Fans may be attached to motor controllers”. Is there something else that I’m overlooking?
There is no rule that explicitly requires you to install a fan on motor controllers. The only rules mentioning fans are R32 and R65, which simply permit the usage of such fans. Nevertheless, you should still raise this question on the Q&A.
Do, however, keep in mind that the Victors are designed to operate with the fans they ship with, not without. Talons are arguably more robust in this respect, as they are designed with a heat sink and the usage of a fan is, in comparison, only “recommended”. As Victors are generally used with fans and Talons are being introduced for the first time this year, there is no reliable precedent for doing what you propose.
Something to consider if it really is that much of a problem would be to use the 10mm fans (as opposed to the 20mm that the Victors come with), and then trim down the securing pins (in the case of the Victors) and use some manner of adhesive to secure them. If you do use this option, however, be sure to first pose this to the Q&A as well, as modifying motor controllers for mounting purposes is not explicitly discussed in the manual.
R65 Does prohibits disassembling/modification. I’m thinking that removing the fan from the victor counts as such but you can apparently attach more fans to it…
R65 would definitely apply, in terms of removing fans from Victors, as the Victors come with the fan pre-installed.
Please note, however, that item M does allow repair, “provided the performance and specifications of the component after the repair are identical to those before the repair.”
I would interpret this to mean you could “repair” a Victor by replacing the fan with one with identical performance specs (specifically airflow). If that fan happens to be half as thick, god for you.
Q81 Q. Is it legal to use either model of Victor speed controller or the new Talon speed controller without an attached fan, provided that adequate airflow is provided in some other way?
A. The only legal modifications to motor controllers are listed in [R65].
My interpretation is that since the Victor comes with fans, it’s not legal to remove the fans. Since the talons do not come with fans, it’s legal to add fans per R65-D.