Welcome to Synthiam!

The easiest way to program the most powerful robots. Use technologies by leading industry experts. ARC is a free-to-use robot programming software that makes servo automation, computer vision, autonomous navigation, and artificial intelligence easy.

Get Started
Asked — Edited
Resolved Resolved by thetechguru!

Power Supply For Jd

First, apologize for my english.
I want to run my robot without battery.
Has ever tried someone?
Can an adapter be tinkered and connected to a universal power supply?
If someone has already built,
I would look over pictures.
thank you


Upgrade to ARC Pro

Get access to the latest features and updates with ARC Early Access edition. You'll have everything that's needed to unleash your robot's potential!

Hi Stiko.
I use a switching power supply 6-12v 5000mA that i had for my rc charger and i have set it at 7.5V.
The model is MW7H50GS if you want to make a google search.
Your English are much better than mine!:)
Thanks for your friendly and fast answer.
Can you show me a picture of the adapter to the Lipoakku plug?
The pole coverage interests me.
Is the battery disconnected from the system during this time?
Or have you installed a changeover switch?

Thanks a lot of.
I must apologize for not reading correctly your post.
I gave you a solution to power up your EZ-B stand alone.
It possible to power up your robot by power supply but you must do some mods at the electrical circuit inside the main body (battery case).
As i don't have the original jd robot (mine is 3d printed) if you can post a photo of the body inside i will give you the way to make the modification. Don't forget that you must have some basic soldering skills.
If you open the body, all you need to do is disconnect the adapter from the ez-b and connect the power supply to it. I dont think there is any issues.
You must use a 3 pole dc female jack so when you connect the power supply, your battery will disconnect from circuit.
Then when you unplug the power supply you can use the battery to power up the robot.
The way MazeHorizonTech describe is the easiest but you don't have the choice to use your battery.
Yes, if you want to be able to remove the plug and quickly change to battery power, you need a dc jack that interrupts the battery and allows the power supply to flow. That could require some modification.
I don't believe a 5000 mAh supply is sufficient for a JD due to the inrush current when a bunch of servos start to move. You will want a 20 amp supply or you will get brownouts. You can also help prevent brownouts, possibly staying with a lower cost 5 amp supply by doing the "super-cap" modification.

See post 15 of this thread: http://www.ez-robot.com/Community/Forum/Thread?threadId=8686&page=2

There are a number of threads on the forum with recommendations for power supplies. I suggest searching on the term "inrush" rather than power supply for better results since the issue being solved is inrush current.

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.

Thank you for your time and help.