Upgrade to ARC Pro

Your robot can be more than a simple automated machine with the power of ARC Pro!

United Kingdom

That will depend entirely on the servo you choose, check it's datasheet to find out it's stall current.

It'll also depend on the sensors you use, there are many "ping sensors" available. The HCSR04 is the one EZ-Robot stock, it's current draw is in it's datasheet which is available all over the internet but also in the datasheet repository I'm slowly putting together.

The current draw of the EZ-B V4 is going to be an unknown to all but EZ-Robot and I am sure they have had more important things to do than measure the current draw. It wont be much.

All of this you should already know, I have deliberately not given the current draw of the HCSR04 despite having the users manual open in front of me. The more you can learn to do yourself the better your experience will be :)


Love it Rich! Teach a man how to be dependent and he starves. Teach him how to farm and fish and he can feed an entire village. ;)

United Kingdom

I'm starting my new years resolution early:) Not that I mind spoon feeding but teach him how to build a robot that can fish and he's a wealthy man :D


Lol , I imagine this resolution is going to have some growing pains. It's funny how "do it your selfers" don't like being told to "do it yourself". :: rolls over laughing::


@ techno pro , it is not listed but looking at the specs and gears it appears to be a variety of tower 995 servo. They use 300 to 500 ma working current and 1-2 amps of current under heavy load- stalled. It looks like it would be a phenomenal idea to test the free turning current , 3/4 load current and stall current. That way the customer has a realistic idea of the power usage from the servos in the store.

United Kingdom

Ping Sensor you want working current which is 15mA. 2mA is idle or "quiescent"

With servos, if heavy duty I always allow for 2.5A stall current if I can't find anything on the servo, that should cover you.

One thing you could do, which is something I've started to do is throw in a current monitor. Adafruit make some which go in line with whatever you want to measure. I put mine between the battery and everything else. Hook it up to an ADC, run the bot on a temporary supply to measure the max current. I'll post a link when I get chance but have loads to do now, someone just left a load of presents under my tree!..

Run a script which records the highest value...

$maxcurrent = 0
$current = GetADC(ADC0)
IF($current > $maxcurrent)
  $maxcurrent = $current

Not to bring back a dead thread but the ez-b v4 Setup im using would be 3 ping sensors, and a heavy duty servo (on separate voltage). If the ez-b is getting 2 Amps, and the heavy duty servo is separate power will it work?

United Kingdom

Well technical it's still an unresolved question - don't forget to mark it as resolved once it is.

Check the datasheet for the ping sensors, they are 15mA each. 3 x 15mA = 45mA. So yes, it should work off of a 2A supply.

United Kingdom

You need a steady 5v for the ping sensors. I expect the EZ-B will run on 5v (it has been posted previously).