Asked — Edited

V4 - My Batteries Are Low, My Batteries Are Low

After whole weekend of working with the new V4 EZB I've been able to get two installed and working over my home network. It was a learning experience and had it's challenges but more on all that in another post, another time.

What I'd like to say here is this;

I'm powering the EZB with a power converter from wall voltage. I don't use batteries so I have a continuous power feed and can supply almost any voltage needed within EZB's power range of operation.

The data sheet for V4 says the voltage for the V4 is between 4.5 & 16vdc. This may be true but if the voltage gets below somewhere between 6 & 7 vdc the board will stop responding and I get a irritating voice loop saying ""My batteries are low, My batteries are low".......... This goes on and on till the voltage is raised and the board is power cycled.

So the bottom line is you cannot power EZB V4 with anything lower then 7vdc or it just stops and nags you for more power. Sounds like my 3rd wife, :P

This also means we cant power the V4 with less then 7 volts and get a lower output voltage on the digital I/O pins. We for sure need voltage regulators for devices needing lower voltages.


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You can adjust or disable the power warning in the Connection Control of ARC.


With all the comments regarding "read the manual" if I may inject a little humor at Daves expense but I know he will love the attention:D .......perhaps the voice should say......"read the manual, read the manual........" (will be waiting for payback Dave:) )


lol, the reason it repeats the batteries are low is to annoy you - on purpose. This is because we sell and recommend LiPo batteries. If you kill a LiPo battery, they don't charge again and need to be thrown out. So having the EZ-B v4 repeat the warning is for your own good:)

However, the battery monitor can be disabled in the Connection Control Configuration - it's a checkbox. Otherwise you can specify the minimum voltage for the battery saver.


I updated the Data Sheet to include information about the low battery warning. I also added the default minimum voltage to the voltage reference chart.

View Data Sheet


This is excellent news! Thanks so much! This makes things a lot EZ'er for me and others using power supplies.


Note that I am getting the "my batteries are low" repeated when the voltage is below 7.2 volts DC.


DJ, you said, "Otherwise you can specify the minimum voltage for the battery saver."

Note that the Low Battery Warning only has two options of either Disabled or Enabled after clicking on the "Connection Control" button, with no settings for adjusting the voltage level. Just to be sure of the voltage actually present, I am measuring the voltage right at the back of the DC plug with load with a digital volt meter.

Is there now another place to adjust the low voltage level setting for when the message of low battery warning comes on?

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Yes there is, no need to do what you did... You can adjust the low voltage warning for your EZB4 in the Connection Control settings in ARC (the first control that you see on your desktop when you first open ARC)... It will set the Low voltage warnings for any or all of the 5 boards.. The TCP settings is also in there...

Your battery may be reading 7.2 (but that is probably without a load on it)... Your battery could still be low, however. As soon as you put a load on it like the EZB4 and servos it will quickly drag the voltage down to and below 6.6v.... This is the default low voltage setting for each of the 5 EZBs in the connection control.... Charge your battery...


Thank you Richard. Okay, I was able to find where to adjust the low voltage setting. And yes, under load the battery voltage was dropping to below 6.4 volts. So, that clears that up.


If you're drawing more current than the ezb v4 can handle, it may also complain about the low battery voltage. At that point, I recommend an alternative power supply or alternative power wires.


Is there a way to get an MP3 file to play at a specified battery level? I've got a file for K-9 where he says "power supply failing":).


lol, that would be really neat - there is no way to replace the audio file. However, you can disable the battery saver and write your own code instead.

Keep in mind that with my example below, you lose the battery saving features of the EZ-B v4. If you drain your LiPo battery too far, it will be damaged.

Something like...

$minBatteryVoltage = 6.6


  if (GetVoltage() < $minBatteryVoltage)

    # Put your audio file soundboard trigger here with controlCommand
    SayEZB("My power supply is failing")

  # pause for 30 seconds between battery checks


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I wrote a lipo monitor script a while ago which had 3 voltage levels which could be adapted from checking the ADC ports to checking the variable.

Check my started topics, it's in there somewhere.



Is there a way to play an mp3 kept on an iphone?

I'm guessing that the Soundboard command will only play files that are on the PC and you'd have to use an MP3 trigger board if you wanted to store the sound filies on the robot itself.



One more question-- if I have to use the MP3 trigger, is there an easy way to get the eye LEDs to blink with the voice? I presume the soundservo method of doing this would also force you to be tied to a PC. I do have a hardware work around (I found a tiny board that uses its microphone to blink an LED, if necessary.



Lol. i open my ezb to see if there was battery inside.


@ftlum.... There are in fact 2 sound boards. One to play out through your PC speakers and the other to play out through the EZB4 speaker....


Do the sound files need to reside on the PC for soundboard and soundservo to work?



All of the files remain on the PC... the difference is the sound would be played out through the PC speakers or the EZB speaker depending on what sound board you are using... There is no Apple software available (yet)....

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The sound files are saved to the project file. I.e. if you added helloworld.mp3 to the soundboard and saved the project you could, in theory, delete the file helloworld.mp3 from the PC or transfer the project to a different PC and the soundboard would still work.

If using the EZB Sound servo and Soundboard the files do not require the PC. In fact, I believe that may work while running from an android device (however I don't use the mobile app so don't know what's currently supported and what isn't).