Rich,

Thanks for the info...and btw: for those reading this thread....just go through the lessons. (I hadn't done that when I made my first comment) They have the information embedded in them for certain things as they apply to all robots...like scripting and power...etc.

Also, should I be looking for a way to step the voltage down to 7.4vdc for the main input voltage before connecting power to EZB controller? In other words, DO NOT CONNECT 12vDC to EZB at all?

BobJ

@Bobjacon

if your are connecting the servos to the EZ-B to power them, then yes. DO NOT run 12v through it using standard hobby servos. It'll fry them. You can easily get a wall plug that'll supply 7v from just about anywhere

Thanks everyone for all the comments. I have already learned a lot more by following your suggestions. I am trying to build a medium sized robot that can do the things the little robots do. I am using two 12 v 9 amp batteries in parallel. For the EZ-B i am using a 14 amp voltage regulator turning the 12 v to 7.2 v. Voltage and amps have so far not been a problem.

I am totally convinced that I will get it but i will have to also some assistance from time to time. It is good to know that it is so readily available.

I know how busy you must be with all the things going on at EZ-Robot. When you find time I agree that there needs to be a good getting starting with EZ-Script to help understand how to put all the scripts in the right places and order.

Thanks again everyone. It is good to have such knowledgeable and helpful people in the community. Ellis

Bob J,

Here's a section of a long personal letter I just sent you. Hope this isn't seen as a continued hijacking of this thread but I think it answers some of the questions Bob raised.

Now as far as power feeds; This can be completed and could take time.  However I'll try to explain. The best way to start with any electric circuit design is to look at each device you have and see what it's voltage requirements are and how many amps it will draw. Add up all the amp draw and you will know how much current your power supply will need to be rated for. Then look at the voltage needs of each device and you will know where you will need to boost or buck the voltage. A lot of electronic devices have a voltage range they can operate in. Try to buy devices that match the power supply you have chosen. In your case 12 vdc is good because there are lots of devices that run at that voltage. If I have to change the power down line of the main power supply I like to buck (decrease) the voltage with a DC to DC power converter.  Make sure you get a power converter that is rated for the peek amp draw of the device your converting to. The best kind if converter is a switching power converter because they are a lot more efficient and produce very little heat (your main power supply should be this kind). However  when you start converting these smaller loads they are hard to find and expensive. With these smaller loads it's OK to use linear power converters. They waist a lot of energy and make a lot of heat but if they are quality and sized to your load you shouldn't have problems. 

With all that said and as I said above you need to design your power grid starting at a main power supply that can handle the load your going to apply to it. Then from there you need to branch off to the different devices (loads) your going to power. You should also fuse each branch line (circuit) at what the amp draw of the devices on each line will add up to. Make the fuse size a little higher then the load. If it blows and you know there are no shorts or problems then up the fuse size a little more. Also place large motors and sensitive equipment on their own circuits. Buy and learn how to use a multi meter and a AC and DC amp probe. They will save your ass some day. 

Here's a good tester I use: http://www.amazon.com/gp/product/B009CNYJG2/ref=oh_aui_detailpage_o04_s00?ie=UTF8&psc=1

When you sectionalize like this it makes it easier to troubleshoot problems and better protects devices from shorts and power surges. This method also helps you balance the total load across your system. You also may find it best to use several main power converters and daisy chain the AC side feed of them together (place them in series).  This will also help isolate any electronic and keep it out of your sound system. Put noisy lights and control boards on one supply and the sound system on another. 

Here's an example of a good adjustable DC to DC linear converter I'm using to decrease voltage from 12 vdc to what ever I need and is rated for 8 amps:
http://www.amazon.com/gp/product/B00C4QVTNU/ref=oh_aui_detailpage_o08_s01?ie=UTF8&psc=1

Now, the EZB will accept anyware from 4 to 17 vdc. It has a power converter on board that will give 3.3 vdc to the power pins on the ADC and i2c ports at a very low amp rating. This is for powering sensors like pots only. The power pins of the digital ports are pass through voltage of exactly the same voltage your powering the EZB with. If you power the unit at 12vdc then you'll get 12vdc at these pins. The amp rating is exactly what your power supply is rated fro because the power is coming from there. EZB has a 20 amp fuse onboard so they say the unit can have 20 amps pulled through it. I dont advise powering any large loads through thi EZB. I've had it brown out while powering a HD servo through it that only was pulling a few amps. Feed all your large loads around the EZB. However make sure they all have the ground wires interconnected. 

You wont need to match the amp protection on the AC side with what your pulling on the DC side of the converters. While your AC amperage will raise a little as you add DC devices beyond the converters it wont be that significant. I have a 6 amp main fuse where the AC power enters my B9. I have many, many more amps then that being used past the DC converters. The converters will take on the extra DC current. 

I hope this helps clear some things up. I gotta go now and watch for Santa. I hear he's bringing me some parts for my B9! 

Have a great holiday!
Dave