cRIO fuse??? 20 or 30?

[mynameisbob]

Im probably an idiot and not reading the right part of the manual, but what fuse should I use for the cRIO 180 pwm thingey? I know I have the wiring and everything right, but ive no clue of the right fuse to use.

[EricVanWyk]

I do not know what you mean by "cRIO 180 PWM thingey". What does the label on the module say?

[LeadCoreWarrior]

The cRIO does not need a fuse. At the end of the Power Distribution Board (PDB) opposite the main + and - terminals there is a place for dedicated 5 volts and 12 volts which are to be used for the camera and gaming adapter and a dedicated 24 volt plug that fits the same plug that also plugs into the cRIO for power. This is where you should be powering your cRIO from and it does not need a fuse. The wiring instructions for the cRIO as well as the rest of the control system can be found on usfirst.org under Control System Documentation, not under the game rules.

[seanl]

are you talking about the sidecar?

[keen101]

"cRIO 180 PWM thingey"

is not very descriptive. The cRIO itself goes to 24v without a fuse as i can tell.

http://usfirst.org/uploadedFiles/200...%20diargam.pdf

http://usfirst.org/uploadedFiles/200...%20diagram.pdf

[EricVanWyk]

Keen, Sean, and Lead -

Thank you for trying to help bob.

However, I must ask you to be careful in this instance. There is a very good chance that bob has not read the appropriate materials, and is therefore much more likely to damage his control system. In the future, please answer questions of this nature with direct hyperlinks to the appropriate section of the manual, with a page number or range included.

Thanks!

[Racer26]

Your cRIO definitely should be plugged into the fuseless (well, I believe its internal to the PD board, but that's irrelevant) 24V port. The sidecars, and breakout boards should be fed a 12V supply from one of the PD board's many other outputs, through a 20A Snap Action circuit breaker. Other than that, you should not be applying 12V to anything attached to the cRIO. I suspect you're referring to the Digital Sidecar (it attaches to the cRIO with a large DB-37 cable). It provides the familiar PWM outputs to connect to speed controllers. It should be fed 12V from a 20A circuit breaker.

[mynameisbob]

Thank you guys for helping me, and yes, i am talking about the sidecar. I knew everything but the right fuse to use.

[seanl]

i don't think that the manual says anything about the fuse on the side car, but i would use the 20 amp because the sidecar probably wont pull that much amps, and in the past we have used 20 amps on the old contollers. so you should be fine with a 20 amp.

[Jon Stratis]

From the data sheet, available in chapter 3 here: http://usfirst.org/community/frc/content.aspx?id=10934

3.5.2 Typical Application
** Always refer to FIRST rules for using this module in competition robots. The following sequence
describes an example application that may not fully comply with FIRST rules.
1) apply power to the DSC via J22 from a 5A (or larger) breaker on the PD
2)[...]

This typical application uses a 5A breaker... i doubt you'll need 30A for a FIRST robot.

Also, the worst that can happen if you use too small of a breaker - the breaker pops, and you put a bigger one in, after determining that it didn't pop due to a short or other hazardous electrical condition. The worst that can happen if you use to big of a breaker - your digital side car, and possibly anything attached to it, could go up in smoke.

[Alan Anderson]

Originally Posted by eagle33199

The worst that can happen if you use to big of a breaker - your digital side car, and possibly anything attached to it, could go up in smoke.

Try to keep in mind that circuit breakers are intended to protect the wires, not the components. If the Digital Sidecar itself pulled enough current to smoke something, it was probably already broken.