Originally Posted by sanelss (Post 1354450)

that's only a recommendation and the safety guidelines aren't really competition rules, they are just that, guidelines. We may not win a safety award but this doesn't seem illegal. Esp considering the chargers state automatic charge current setting with no specification for capacity rating so we believe we are working well within the design constraints of both the battery and charger. Worst case we use a 6A charger for bulk charge then these for top off and consistency guarantee.

Originally Posted by Safety Manual

This manual applies to anyone involved with the FIRST Robotics Competition including all student team members, Mentors, and support personnel.

Originally Posted by Steve W (Post 1354443)

I am sorry to disagree with those that state there is no rule about chargers. It is found in the safety manual and as LRI's we have been told to enforce it. The highlight is mine but a direct quote. From the safety manual:

"Charging and Handling
 Keep the battery-charging area clean and orderly.
 Place your battery charger in an area where cooling air can freely circulate around
the charger. Battery chargers can fail without proper ventilation.
 Do not short out the battery terminals. If metal tools/parts contact the terminals
simultaneously, it will create a direct short circuit. This may cause high heat to
develop in the battery terminal/part/tool area and the battery could explode.
 If a quick disconnect is not available and you must use tools to disconnect the
battery, make sure metal tools don’t contact both terminals at the same time.
 Do not charge battery at greater than the manufacturer’s maximum recommended
rate."

Originally Posted by BigJ (Post 1354454)

You can argue however much you want about how it isn't really a rule, but when the LRI tells you that it's not allowed to be used on your robot batteries, you aren't going to win. :rolleyes:

Originally Posted by sanelss (Post 1354459)

We consider the safety manual as guidelines not competition rules. If everything stated in that manual were enforced then every single team would be disqualified for one reason or another. Also the chargers state they automatically set he charge current. Even if they do deliver more than 7A it's not for a very long time either. Worst case is we do bulk charge on old 6A chargers then top off with these. That way they never do get charged higher than 6A but this is just playing around a technicality and more or less on a guideline rather than a competition rule anyway. Either way it won't really be an issue if that's all we have to adhere to.

Originally Posted by luckof13 (Post 1354458)

Except that the Safety Manual is not just guidelines.

The spec sheet for the battery that I linked to in my post above states that the maximum charging rate for these batteries is 5.4A. You will damage you batteries if charge them above this rate.

Originally Posted by sanelss (Post 1354460)

then we'll just play around it. do bulk charge on old 6A and top off with these, win-win?

Originally Posted by sanelss (Post 1354466)

From other online documentation I found there is no danger at charging up to 1C other than shortening the battery life, which you may consider damage I suppose though. Honestly i'm no worried since we can work around it by bulk charging on 6A then cycling to these for top off

Originally Posted by luckof13 (Post 1354463)

The charger you linked to is meant for car batteries, not FRC batteries. The charger does not know that the battery connected to it is not what it is designed for.
The safety rules are rules, and you will be told to follow them.

Originally Posted by GearsOfFury (Post 1354467)

At the week 1 event I inspected at, our LRI (Al) specifically asked us to look for chargers that operate above 6A, and instructed that they WOULD NOT be allowed, regardless of how you told us you would "program" or use them. OP there is no way for us to enforce that you are following what you are suggesting. I would highly recommend you bring other (i.e. legal) chargers to your event and consider leaving these at home.

Originally Posted by sanelss (Post 1354473)

Even so we can easily adhere to the rules by bulk charging on old 6A then cycling to these for the top off

Originally Posted by efoote868 (Post 1354470)

1C for a 40AH car battery is different and bigger than 1C for a 17AH FRC battery.

Originally Posted by sanelss (Post 1354448)

It's not that we limit it, it's that they simply aren't sufficiently usable. We have batteries going back a few years and 2012's and back simply don't perform as required

Originally Posted by tim-tim (Post 1354492)

How is "cycling to these for the top off" adhering to the rules? If you can't use them, you can't use them.

Adhering to the rules would mean to use (and only use) LEGAL chargers at ALL times, while at the event. This would mean that the batteries never see the charger you are suggesting.

Save yourself the headache and space by leaving the charger at home when you compete.

Originally Posted by sanelss (Post 1354473)

actually it makes no claim as to what types of batteries it can and can't/shouldn't charge. The only indicator is: "automatically selects charge rate from 0 to 15 AMPS to maximize battery life, charge speed and maintenance"