Battery Question?
 

Is there anything in the rule book that I might have overread that says you cannot lay a battery on its side? Id appreciate some answers :D

Re: Battery Question?
 

It should be ok. Our teams rookie year we put the battery in sideways. It could have changed since then though.
Joey

Re: Battery Question?
 

Nothing against it this year--or in recent memory.

Re: Battery Question?
 

It's fine :cool:

Re: Battery Question?
 

Thanks for the help!:)

Re: Battery Question?
 

the sealed lead acid batteries used in FIRST can be used in any orientation and are generally a very forgiving battery in terms of how much abuse it can take before it is no longer useful. almost all the conditions it goes through in a FIRST regional are far outside of what the battery is intended to be used for, such as draining it to 9 volts in 4 minutes. only thing I really have against these batteries is the rules about not being able to use other brands of batteries and this business about using only 6amp automotive chargers in the rules, which I don't recall being in previous years.

Re: Battery Question?
 

This has been in the rules all the way back to at least 2002. It is really unsafe charging these batteries faster then 6 amps.

Re: Battery Question?
 

its not that which I'm unhappy about. its the problem of having several other very nice battery chargers that are under, not over, 6 amps. the 6amp chargers they give us are for automotive batteries, and I cant use any of the POWERSONIC SLA chargers because they are 4 amps, not 6. the rules are pretty specific about it being 6amps and only 6amps. I would much rather use a temperature compensated SLA charger designed for SLA's than some random automotive chager with a software glitch that prevents it from charging if only the red light comes on untill I plug in a battery, wait, unplug, wait, and plug back in then set the charging rate by pressing a button until the setting I want lights up. (if you cant tell, Im not impressed by the current KOP battery charger.)

afterthought: it isn't safe charging them faster than 6 amps, yet its safe to discharge them at 80amps? I'm not attacking your post or you in any way, I'm just generally unhappy about the battery rules and for some reason extra unhappy right now.

Re: Battery Question?
 

In the past the rule...
<R48> The ES17-12 shall only be charged between MATCHES by a 6-ampere rated automatic
battery charger. When recharging the Kit Of Parts batteries, either the charger provided by
FIRST or an automatic charger with an equivalent charging current rating may be used.

has been interpreted as to allow the lesser current. First provided 4 amp chargers many years ago when we first started using the 12 volt gel cell batteries. If you are concerned, please ask the Q&A. Yes we are stressing the batteries at the load we place on them, but it is for only two minutes. A high current charger left on for several hours is likely to produce excessive heat in the battery which can produce some nasty venting of gas and damage to the internal assembly.
Yes, I have seen teams bring in fifty amp chargers and hook them up with aligator clips in the pit. I hate the smell of sulpheric acid and burning plastic in the morning.

Re: Battery Question?
 

Lead acid batteries when charged can generate quite a bit of heat when charged at a fast rate, and actually charging a 17Ah battery at 6 amps is rather fast (C/3), where it is deep cylce you won't run into the problems like you would with an automotive battery if you "cook" it with a very fast charge, with the automotive batteries you can actually "sluff" of plates of the battery and possibly cause it to vent, especially with the increased temperature and also with the gases that are generated during charging, which in a side note is also flamable...

Those are just some of the reasons that you dont want to charge especially a sealed lead acid battery at more than C/3

Tim
Batteries Plus
New Hampshire

Loooking for extra batteries, check out my white paper !

Re: Battery Question?
 

i read that the battery terminals have to be at least 4 inches form the ground

Re: Battery Question?
 

No rules about that...Or can you quote one?

Re: Battery Question?
 

There are advantages and disadvantages of putting your battery upright or laying down. You must determine which one suits your robot the best.

Re: Battery Question?
 

That's a new one. I have never seen a battery rule about height above ground. However, if the battery falls out of your robot and is being dragged around, you will be disabled.

Re: Battery Question?
 

I only see 2 robot rules that include the phrase "4 inches":

"<R15> The judges, referees, and announcers must be able to easily identify ROBOTS by team
number. Teams shall display their team number in four locations at approximately 90-
degree intervals around the perimeter of the ROBOT. The numerals must be at least 4
inches high, at least in 3/4 inch stroke width and in a contrasting color from its
background. Team Numbers must be clearly visible from a distance of not less than 100
feet."

"<R18> ROBOTS must use the LAP INDICATOR provided by the field personnel during all official
tournament MATCHES. The LAP INDICATOR is attached to the stopper on the flag pole.
When the FLAG is placed in the flag holder, the stopper will insert into the top of the holder.
To accommodate the LAP INDICATOR, the area within a minimum 180—degree horizontal
arc around the top of the flag holder must be kept clear of any obstructions within a 2-inch
radius. This region must be kept uncovered and visible from above. To ensure that every
FINISH LINE CROSSING is properly recorded, the LAP INDICATOR must be visible to the
Lap Detectors when the ROBOT passes under the OVERPASS. The LAP INDICATOR is
powered via a standard three-wire PWM cable. An easily accessible, powered, male PWM
connector must be located within 4 inches of the LAP INDICATOR mounting location. The
port may be either a direct connection to an analog or digital port on the Robot Controller, or
a remote “pigtail” connection to the Robot Controller port."