Pneumatic Regulators from Automation Direct

[Al Skierkiewicz]

Paul,
I am simply referring to a part that has been either recommended or required for many years (at least to 2010). Why is everyone so opposed to using a tried and true device? The rules have not changed that much, using nearly identical language...

R82 “Working” air pressure on the ROBOT must be no greater than 60 psi and must be provided through a single primary adjustable, relieving, pressure regulator.

Norgren regulator P/N: R07-100-RNEA or Monnier P/N: 101-3002-1 recommended.

Not "required".

[AllenGregoryIV]

Originally Posted by Al Skierkiewicz

Not "required".

Al, I think Paul wants a clear cut answer on weather a regulator like this one (http://www.automationdirect.com/adc/...Series)/AR-213) is legal. I don't think anyone is trying to prevent teams from using the Norgen regulator.

[Aren_Hill]

As Paul stated, we are currently competing with the tiny regulator from automation direct, we used it because it is very small, light, and cheap.

My brother Kellen used these last year as well with 1746, they are a proven technology and I enjoy the benefits and do not see why anyone would use anything else.

Actually, pulled the catapult off yesterday, so there are no pneumatics on the Bot, but it did pass inspection.
-Aren

[Chris_Elston]

Originally Posted by Al Skierkiewicz

Why is everyone so opposed to using a tried and true device?

We chose the Automation Direct one because it has an integrated gauge. In the beginning of the season, you could not get the white gauge from AndyMark, so we went looking somewhere else. Now that gauge is in stock. Also, it seems the gauge needle breaks for some reason in the white or norgen gauge, we've had several problems with the gauges not the regulator. So, like about 1/2 the people on this thread is seemed to us it was a legal device, didn't even think twice about it, we printed the spec sheet and have it in the same book as the robot bag and tag form ready to show the inspectors. That was why we went looking at something else.

[Paul Copioli]

Al,

You asked a direct question about the Norgren valve and I will answer it.

we have had terrible hysteresis problems with that valve and it is mostly related to it being used at the extreme of its working envelope.

Also, for this season the fact that the Automation Direct valve is so small is a huge bonus.

Paul

[Tristan Lall]

I'm inclined to continue using the past interpretation of the rule to resolve the Norgren issue in favour of legality. Since a Norgren R07-100-RNEA regulator can frequently¹ be adjusted above 50 lb/in² (the manufacturer's operating limit²) and even above 60 lb/in² (the R77-I limit) using the provided control knob, and FIRST should know this, I would interpret the "maximum outlet pressure" to mean the maximum non-transient pressure at the outlet given a certain user-adjusted setting, rather than the manufacturer's published operating limits or proof limits. This also permits R75 to be read without conflict: the "working pressure" referenced there should be interpreted in terms of the possible range of input pressures, not the adjustment range of the outlet.

Using that logic, the AutomationDirect valve, the Nitra AR-213 is also legal. For R77-I, you must adjust its outlet to 60 lb/in² or less, and the datasheet states this is possible. For R75, the "working pressure" at the inlet should be no more than 145 lb/in² if like the Norgren, you may operate it in excess of recommendations, or no more than 130 lb/in² if you must stay within the manufacturer's range. Either figure satisfies R75.

Also, for anyone concerned about unsafe failure of the regulator, Nitra conveniently provides proof limits: below 215 lb/in², you should not expect the regulator to fail catastrophically.

For better or worse, guidance provided to LRIs is not inherently a rule, and cannot be enforced.

¹I don't know what the production variation is on the physical limit of adjustment, so perhaps I'm relying on outliers to reach that impression.
² For regular customers at least. I seem to recall, but can't document, a Q&A from the early 2000s alluding to Norgren telling FIRST that operating this regulator up to 60 lb/in² was acceptable.

[martin417]

Has anybody submitted a Q&A on this topic? Would be nice to get clarification before the next event.

[Holtzman]

Originally Posted by martin417

Has anybody submitted a Q&A on this topic? Would be nice to get clarification before the next event.

Yes.

[FrankJ]

Originally Posted by Holtzman

Yes.

It might be good to point out to the Q&A people that the recommended regulator can be adjusted to above 60 PSI.

[Holtzman]

Originally Posted by FrankJ

It might be good to point out to the Q&A people that the recommended regulator can be adjusted to above 60 PSI.

Ya, the original question was quite a bit longer and pointed out all the important details touched on in this thread. There is a character limit on q and a's that made adding more details impossible though.

I could have linked this thread, but I suspect the deciding parties are already aware of whats been stated here.

[AllenGregoryIV]

Originally Posted by Holtzman

Ya, the original question was quite a bit longer and pointed out all the important details touched on in this thread. There is a character limit on q and a's that made adding more details impossible though.

I could have linked this thread, but I suspect the deciding parties are already aware of whats been stated here.

Yeah I've been trying to get them to remove or at least liberally increase the character limit for a couple years. I think they made it a bit larger last year but still not good enough. VEX Q&A forum is still better at this, they can post photos and things to help communicate their questions.

[FrankJ]

Q & A has spoken with much appreciated clarity.

Q. Is the intent of R77I to limit teams to only using Pressure regulators with a published operating range of less than 60 PSI, or is this meant to allow regulators with an operating range above 60 PSI provided they are adjusted such that the working pressure is at or below 60PSI?
2016-02-27 by FRC2056
A. The meaning of R77-I was unclear, sorry about that. It will be revised in Team Update 14 to allow pressure regulators with the outlet pressure adjusted to 60 psi or less. Regulators with an operating range above 60 psi will be allowed provided they are adjusted to no more than 60 psi.

[Jon Stratis]

And that just made inspecting pneumatic systems a lot easier than it was looking over the past week!

[Karthik]

Originally Posted by Jon Stratis

And that just made inspecting pneumatic systems a lot easier than it was looking over the past week!

Indeed. This was a smart answer fueled by common sense on the part of the GDC. Definitely helpful to teams and volunteers alike.

[Paul Copioli]

Once again the GDC under Frank Merrick's leadership is the most professional and most reasonable during all my years of participating in FRC.

The practical and team centric approach that FRC has been taking during the "Frank Era" of FRC is very much appreciated.

What a courteous and professional response.

Paul