12v and 24v solenoid

[Mark McLeod]

You cannot hook both 12v and 24v solenoids to a single common solenoid breakout in one slot. The solenoid breakout can only be wired to one or the other, 12v or 24v. It's not dual voltage if that's what you are suggesting...

We do have two solenoid module slots (7 & 8) to use. You can make one 12v and the other slot 24v. Same as last year.

[Team#2057-Vegas]

hmm.. interesting.. thats what we did last year and it was just fine.. everything wired to the 24.. it all seemed to work just fine.

[Gdeaver]

Looking at the wiring diagrams the solenoid module is shown connected to the 24 volt connection on the PD. Absent is the alternative connection to the 12 volt connections of the PD that were shown last year. Strict interpretation would say 12 volt solenoids are not allowed unless connected to spikes.
I would rather not have solenoids switching on the power supply that also supplies the brain but, that is what FIRST has done.

[Mark McLeod]

In that power diagram they only demonstrate the solenoid module in slot 7.
In the data diagrams they only show the show the solenoid module in slot 8.

So, by strict interpretation we can either power one solenoid module from the 24v without connecting any solenoids to it.
Or we can connect solenoids to a different solenoid module, without connecting any power.
- adventures in reading the manual...

[Al Skierkiewicz]

You may have no more than one solenoid module connected to the 24 volt output on the PD if you are using 24 volt solenoids.
<R38> All electric power utilized by the ROBOT shall be distributed from the load terminals of the PD Board. Circuits may not bypass the PD Board to connect directly to the 120-amp loop.
A. The cRIO-FRC power input must be connected to the 24 Vdc supply terminals on the PD Board. With the exception of one Solenoid Breakout Board, no other electrical load can be connected to these terminals.

You can have another solenoid module connected to 12 volts and driving 12 volt solenoids. It appears that the wiring diagrams are demonstrating connections for specific devices not a generic wiring of all possible configurations.

[Abrakadabra]

Can someone please clarify the 24V power out pins on the PD? A close reading of all the Robot rules as well as the manuals for the PD and the Solenoid breakout* did not reveal their meaning to me:

The 24V output pins are labeled: V - C - NC - C

We wired cRio positive (red) to V and negative (black) to the C immediately to the right of V.

We wired solenoid breakout positive (red) to NC and negative (black) to the remaining C terminal.

Is this correct?


* In fact, the manual for the solenoid breakout only tells how to wire it for 12V, not 24V.

[Al Skierkiewicz]

Scott,
To be sure you are listing the wiring you performed at the PD end of the Crio cable? If so that is a correct way to provide power to a 24 volt solenoid module. Make sure before you insert the connector that you don't have any wire whiskers sticking out and touching adjacent wires. This is the most common failure for Crio power followed closely by wires pulling out of the connector.

[EricVanWyk]

Originally Posted by Team#2057-Vegas

hmm.. interesting.. thats what we did last year and it was just fine.. everything wired to the 24.. it all seemed to work just fine.

Yep... but if you had any 12V coils being powered by 24V, you were severely overpowering them. It could be that you never had them on long enough to release the smoke.

Can someone please clarify the 24V power out pins on the PD? A close reading of all the Robot rules as well as the manuals for the PD and the Solenoid breakout* did not reveal their meaning to me:

The 24V output pins are labeled: V - C - NC - C

It is labeled V - C - NC - C, but it is actually wired V - C - V - C, meaning +24V - GROUND - +24V - GROUND.

Sorry for the confusion. The history here is that the cRIO is wired as it is labeled, and we reused the connector. I thought we might need the extra 24V tap, so I wired up the NC pin.

[Mastonevich]

It appears to be the same rules as last year.

From what I am reading you can have two solenoid breakouts, one at 12V and one at 24V.

Can you have two at 12V? I read that rule to state you can only have ONE at 12V.

[Mark McLeod]

Up to (2) at 12v
Only (1) at 24v