Asked — Edited
Resolved Resolved by Niek!

Another Question For Josh Or Anyone


On the two 12V batteries that you order from Ebay, Which charger can I use? I have a Large Car battery charger and a small Motorcycle Battery charger. Does these batteries require a certain charger to use?

Thanks in Advance, mel :)


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You can use either charger, just double check that the motorcycle charger is for 12V batteries ;)


If it helped, please mark the question as resolved :)


Hello Mel , check the charge rate for the motorcycle charger. And seen if it matches the specs for the battery. Some motorcycle chargers are reffered to as "battery tenders" and can have charge rates lower than one amp. That would never charge the battery so make sure your charger can do a minimum of 1.5 amps or higher. Batteries slowly loose charge over time and these battery tenders just keep it topped off at a very low rate. The car/motorcycle chargers that are rated 5 to 6 amps or 5000mah to 6000mah are going to be best for charging two batteries at once. Schumacher makes descent chargers that are sold at walmart I like to use. Moral of the story is make sure the charge rate meets the minimum requirements of the battery then remember to double the requirements because your charging two.


the motor cycle battery charger is 1.5Amp.

My car battery charger is 12volts ,10Amp, except start engine which is 55Amp. It also has a 2Amp setting. So, I guess I will put it on 10Amp.


Check your battery specs to see if each battery is recommended to charge at 5 amps. For bigger sealed lead acid batteries it's fine.


The battery is the same Exact ones that you got for $37.50 a pair.


As long as your are charging 2 or three batteries in parralel that will work. It may get warm if you charge one at 10 amps by itself


The question is: How am I going to operate the arms and the hbridge on a different power source when i have them both in parallel to charge?

I was originally going to use two 6v one for each EZB and 12v for the arms and another 12v for the wheels. But, everyone said use all the same voltage. So, I took the 6v out of the circuit and I am trying to decide HOW to wire the rest of it. It is very confusing.

Thanks for your help, Josh!



Ok I can see your confusion. Let me illustrate it.


It's easiest to wire the batteries parallel meaning all pos and all neg together. It makes two batteries combined into one. There is no reason to not do this. When charging you connect to the pos and neg of that battery bank you have created. The ezb and all other equipment can connect to this 12 volt battery bank. If anything like a servo needs lower voltage use a regulator to drop the voltage to that particular device. Usb runs on 12 volt just fine. Here's a drawing.... User-inserted image


Don't bother using a separate 6 volt battery just use a regulator like the ones you see everyone else using. There's no reason to complicate your setup.


Thanks, Josh. I have since ordered two more 12volt batteries. I will be adding one of these to the group. One for EZB, one for Arms, one for Motors. I will put 7.2reg on the ezbs, 7.2regulators on the arms and 12vRegulators on the wheels. Is this right? I will add them in parallel also. so, I will have 3 batteries to charge at once from my 10amp charger. Is this correct? It will just have the new battery added to the stack. But, with this configuration, will the EZB try to regulate 5volts to the servos? Will that waste a lot of power? I really need to make the separate with them in PAR to charge only. What do you think?

sorry to be so dense.




Yes three 12 volt batteries all parallel will charge well on a 10 amp charger. There is not need for a regulator for ezb there is already two 5 volt regulators on the board. You only need a regulator for other devices like servos if you use external power. The power pins on the ezb board yes are 5 volts but I would save that for sensors. Any motors or servos use their own seperate regulator.If you are using high torque servos external power is the best way to go. With a 12 volt supply you can charge the batteries without disconnecting anything or even turning ezb off. I think with three batteries like mine you will have plenty of juice. That's 27 ah at 12 volts or 324 watt hours of power. Take in mind those batteries are 6 pounds each that's 24 pounds of batteries so just make sure whatever you mount them to is sturdy and tie them down with Velcro straps.


I will be using three 12volt batteries from the PowerSonic two pack. This was the ones that you suggested. I also have the servo cable adapter so that you can use separate power to the servos directly. It supports 8 servos. This will be my arms. The 12volts will go through the regulator to the H-Bridge. I am not going to use 6volt at all just 12vdc. and three batteries total. So, don't regulate and hook 12 directly to EZB?

I got the charger thing down with the three 12volt batteries in PAR. I understand that. But, when I need an external source, that is where I am having a problem. I was going to regulate to 7.2 so the ezb had the Ideal voltage on them.

would you say those Powersonic twin packs were sealed acid batteries, or gel?

Sorry for all the questions. I am suffering from a Brain DisOrder called ADD. I have to repeat and parrot thing back so I will understand. It takes a while for it to seep in. My ADD gets worse with age.

Josh, Thanks for being so kind and understanding.


Yes hook Ezb directly to 12 volt

Use the external power not the EZB

Hook 12v to a Regulator and drop it to 7.2 volts . use that 12 volts from the regulator to power the servo

The batteries are probably sealed lead acid , and if they are like mine they are Gel filled but that just means they resist vibration.

User-inserted image


OK, now I have it. I am a little dense. But, finally, I understand. I have that servo pc with the 8 servos on it. That will work well.



Great! , what I would do is take notes as you go so that when it comes time for you to wire things up you are confident and have something to quickly reference as you go. Just a spiral notebook and even make your own drawings. Every scientist has to take notes. Like they say at my job here in the wireless industry " if you can not reference your documentation to confirm your answer you are just making an educated guess and guessing is not for sure"