Thanks for the helpful replies. I never thought the so small servos could need so much energy. This is really amazing. Unbelievable, what a small battery makes. At 20 amp I leave the fingers of a DC jack. I know this from the flight model building and is too dangerous. Lipoakkus are too sensitive to short circuits. JD is too expensive. I have found a power supply of Graupner with 20A and 5-15V for model building. I hope this will work. How long can I run JD on the power supply? When should I give him a break? Can overheat if the duration is too long?thank you cool

The servos can overheat from too much use in short duration, particularly very quick back and forth. The EZ-B itself is unlikely to overheat even if powered on forever.

I don't think there are any hard and fast rules about how long you can run the servos before giving them a break, depends too much on what they are doing and the load being placed in them. Balancing on one leg or holding the arms out straight will cause more strain then just walking around. You'll need to do some trial and error. If the servos feel warm, give them a break.

Alan

Thank you for your time and help.

Thanks