Vex Powerpack (quick dying battery)

Hi everyone, I have a question about he vex power pack I bought from radio-shack about a month ago. I haven’t had much time time to toy with it until about a week ago. It seems like the battery dies within abut 5 minutes of playing with it. I find this odd behavior, especially after letting it charge for over 3 hours like instructions say. Is this normal behavior or is mine particularly defective. Here are my robots specs:

2 servos
underneath a

Box Metal Frame

attached to
4 wheels

Being a first timer I just followed the design from the binder.

Please reply to this if you have an answer. Thanks!

:slight_smile:

its possible your charger is not working. Do you have a meter? Can you measure the voltage on the battery, after its been charged?

No, the charger doesn’t come with a meter,sadly, but maybe my only choice is to by a new one. Thanks for your input though.

Have you tried asking Barry (from your team)? I know he tinkers around with Vex, and might be able to help you with the problem.

Oh man I forgot he had Vex! Thanks alot Ill call ASAP.

before you run out and buy a new battery or charger, check with RS. I dont know their return or warranty policy, but a month is not very long.

It may be the design of how you have your motors laid out. With my 2 speed vex bot, I cannot drive it in high gear that much because it acts like it has a dead battery, but it is actually the servos overheating. On the robot controller, when the battery is dead, the power light will turn red, or flash red if it’s almost dead. Maybe try to change your gear ratio. I’m not sure what my gear ratio is, but i know it goes really fast. A simple trick that might help is spraying WD-40 on the gears and bushings. If it is the charger, Radio Shack usually has a 90 day warranty. First try to check your gear ratio, then bring the charger and battery back to Radio Shack. Hopefully I left you some good advice.

OK… so this is the standard square bot that’s inside the binder, etc. etc. Should work without a problem as long as the battery is charged. So what I would first do is charge the battery again. If the light is blinking after a while, I know it might be risky but unplug, and charge again. Might be worth it, because I have had such a problem with my battery and doing that just ONCE has improved the battery life a considerable bit.

But if that doesn’t work, then look into the warranty thing. Just be sure to try everything

The highlight there is mine.

If the light on the charger is blinking then the charger is in “fault state”. The most likely cause of the problem is the way the battery is positioned in the charger, which confuses the charger because it doesn’t know if it has to charge the 9.6v transmitter or the 7.2v robot battery.

To fix the problem, unplug the battery, and take it out of the charger. On the bottom of the battery slots on the charger there are little buttons that are depressed when the 7.2v battery is in there. If you try charging a 7.2v battery and the battery is not properly in the slot, then the charger will freak out and give you the blinking LED fault state.

To fix this, always make sure you make sure the battery is fully seated in the battery holder, and then plug it into the connector directly in front of the battery. If you do this, you will never see the blinking LED again (fault state), and your batteries will charge fine.

Yeah, make sure you are properly seating your batteries, to avoid the fault state. Also, make sure that everything is connected properly on your robot, controller, and charger (always check when something goes wrong).
You might have a faulty battery or charger though. :confused: