clarification of rule <R44> on the "The Robot" section

[mobilegamer999]

<R44>The 12V battery, the main 120-amp circuit breaker, and the Power Distribution Board shall be connected as shown in Figure 8-6. In particular:
A. The battery must be connected to the ROBOT power system through the use of the Anderson Power Products (APP) connector.
B.The APP connector must be attached to the battery with either the copper lugs provided in the BURNDY Bag or appropriately-rated and -sized lug connectors.
C.The battery terminals and the connecting lugs must be insulated with shrink tubing and/or electrical tape.
D.The main 120-amp circuit breaker must be directly connected to the hot (+) leg of the ROBOT-side APP connector. Only one 120 amp main circuit breaker is allowed. This breaker must not be bypassed.
E.The Power Distribution Board must be directly connected to the APP connector and main 120-amp circuit breaker. No other loads may be connected to the main 120-amp circuit breaker.
F.Each primary power connection between the battery and Power Distribution Board must be made with 6 AWG red and black wire or larger
G.The 120-amp circuit breaker must be quickly accessible from the exterior of the ROBOT. It is recommended that the 120-amp circuit breaker location be clearly and obviously labeled to permit it to be easily found by field personnel during a MATCH.
H. The Power Distribution Board and all circuit breakers must be easily visible for inspection at each FRC event.

ok, i have a question on part H of that rule.
i don't know how "easily" visible our power distribution board would be. we have a 2 tiered component layout with our first layer containing our power distribution board but it isnt the most easily visible component we have. (Detailed pic will be provided an about a day or so). But basically theres about 4-5 inches of open space between the bottom and top level but sadly they are both made a black plastic material so seeing through them is not an option.

[Chris is me]

I would ask the FIRST Q&A for all non obvious rules interpretations, including this one.

[kevin.li.rit]

Originally Posted by mobilegamer999

ok, i have a question on part H of that rule.
i don't know how "easily" visible our power distribution board would be. we have a 2 tiered component layout with our first layer containing our power distribution board but it isnt the most easily visible component we have. (Detailed pic will be provided an about a day or so). But basically theres about 4-5 inches of open space between the bottom and top level but sadly they are both made a black plastic material so seeing through them is not an option.

It sounds like it's not visible enough. Usually easily visible means you can see it when standing up a couple of feet away. Switching to a clear plastic mateiral may do it for you depending on what it looks like now.

[apalrd]

After asking Q&A, think about what the intent of the rule is. The intent is to not bury the PD board so you can see the lights and read the breaker values on it. As long as you can see it without sticking your head in the robot, you should be fine. In 2009, ours was about 1' under a roller/conveyor, buried in 6" of folded sheet metal, meaning it was not easily visible from a few feet away but visible from a foot or so, enough to read the values on breakers and see the lights. A past robot (2006) had no place for the controller, and the rules dictated that the lights had to be visible. It was mounted on perforated aluminum hanging under the rotating ball sorter, of which the bottom was made out of polycarb and had an open top. You could see the lights if you looked directly over it with no balls in the sorter, and it passed. If you had to modify the wiring you probably would have had to remove the ball sorter.

Remember, my opinion dosen't count. Only that of the GDC does, ask them.

[Mike Betts]

Ben, et al,

Regardless of the GDC answer, the inspector will need to inspect the breaker values and wiring to insure that all rules are met.

We would appreciate it if you did not force us to ask you to dismantle your robot in order to accomplish this.

Regards,

Mike

[Al Skierkiewicz]

Mike is trying to tell you here, that the electrical wire size and breaker value rules are linked together. An inspector must be able to determine which breaker is feeding which wire in order to determine if the rules are met. We will try to make that determination with the robot assembled. If we cannot see the wiring and breakers, then you will have to disassemble to the point that you can demonstrate you are compliant.

As to being able to see indicators on control system components, that works in your favor as well as inspectors and field volunteers. When you are on the field and non-functional, we will try and diagnose and allow you to make changes to give you and your alliance a chance to play every match. If you take away the ability for us to help you through diagnosing, your alliance partners will be playing one robot short. This does not go unnoticed among participants and the result may be you watch instead of play on Saturday afternoon. Your decision.

[mobilegamer999]

heres a bad picture of the component system from a video(ill have a much more detailed picture tomorrow). the PDB is mounted roughly right under the cRio and from the backside you can see all the lights on it (5v/12v/24v) and you might be able to see all the breakers with a flashlight. and as far as the other side goes you can easily see the connections from the 120 amp breaker to the PDB.

[kevin.li.rit]

A clear sheet of Polycarb looks like it might do the trick.

[Mike Betts]

Ben,

Polycarbonate may help but I'm not sure that it will be good enough. It depends on the layout of what is below...

Mike

[Cascade]

Agree with Mike and Al. Having the board easily accessible is to your advantage, as well. You never know when you will need to check the board, breakers, or tighten something. Always good to be able to get to all your electrical components easily and quickly. Wires connected to Victors is another place you will want easy, good access to.

No doubt the need to do this will occur two minutes before the final match for the Regional Championship, as Mr. Murphy would say.

[mobilegamer999]

@Coffeeism
i dont think polycarb will work for us, we already had our components mounted on 3/8 plexiglass but we kinda broke that lol

@rest
the top layer of components is easily removed with 4 wing nuts so while getting inspected would it be allowed to remove the top layer for inspection or do you think we really need to go with a different layout or a clear substance on the top layer.

[kevin.li.rit]

Originally Posted by mobilegamer999

@Coffeeism
i dont think polycarb will work for us, we already had our components mounted on 3/8 plexiglass but we kinda broke that lol

Polycarbonate is much stronger than Plexiglass(Acrylic). If you're breaking it, you're doing something wrong...

[EricH]

The standard tests for what clear plastic is are as follows (choose one):

A) Drill a hole. Plexiglass cracks; Lexan (polycarb) doesn't. There are ways to avoid the cracks, but in general, this works.

B) Clamp one end to a solid surface and hit it with your biggest hammer. If it breaks, it's Plexiglass.

C) If it still has the backing on it, read that.

[Mike Betts]

Ben,

Please read this post.

Mike

[Al Skierkiewicz]

Originally Posted by mobilegamer999

the top layer of components is easily removed with 4 wing nuts so while getting inspected would it be allowed to remove the top layer for inspection or do you think we really need to go with a different layout or a clear substance on the top layer.

In many cases, a removable upper section would suffice. The decision is still up to your inspector. The ability to diagnose and repair quickly still remains.