Hi,

I bought s couple of sBrick plus some time ago, and used them in few MOCs. The last MOC was the Madoca's Avtoros Shaman. In that one I clearly see repeatedly the same two issues:

-after 1-2 min of continuous use, the power output drops. If I keep using it, it keeps reducing until completely stop. 

-sometimes, there's a lag. I mean, in the Avtoros, there are 2 servos to control The 2 front and the 2 rear axles. Sometimes, the front axles turn (or return to original position) but the other 2 axles don't turn until I stop the vehicle. 

In all cases, the power supply are 2 battery boxes with full charged 2400 mA AA batteries. 

Any idea? 

Thanks in advance!

Not experienced either of these.  Which app are you using to control it?  What temperature and voltage are the SBricks reporting when you're seeing the problem?

I'm using the sBrick app. Il check temp and voltage! What values should be ok?

Thanks!

Fully charged NiMH batteries should be around 7.2V, so if it's less than 7V fully charged you have a problem.  My SBricks generally seem to run at around 32C.  I can't remember if the SBrick app does it, but you can get the SBrick Pro beta app to give you a live voltage read out, which would be useful to see what the voltage is dropping to under load.

You say you have two batteries and two SBricks: do you see the same problem with both, or can you isolate the problem to one of them?

Lego motors have thermistors in them which will drop the power if they get too hot, which might explain the progressive power drop you're seeing, but I wouldn't expect that to have a knock on effect on the servo.

My first guess would be a problem with the power source, so I'd check the voltage you're seeing on the battery boxes, and if that's low, check each cell individually.

It may not be the SBrick. I run mine with an Apple device and there have been problems since Apple’s latest updates. I believe SBrick is working to fix this. I have 2 SBricks in a model with 6 drive motors and everything shuts down after 30 seconds. Reboot and I have another 30 seconds. It used to work well. If you’re using Android then I don’t know. There’s not much to go wrong with SBricks, it’s usually a system issue. Try contacting SBrick with your problem, they will get back with you. 

Edited January 17, 20214 yr by u118224

Many thanks for the replies! :)

I will try to test the sbricks with few extra models and check theit behaviour in terms of performance, temp and voltage. I think, although I am not sure, that runing the Avtoros, both sbricks worked at about 31-32ºC, which seems to be right.

@u118224, indeed, it may be a system issue. I run in Android, but similar problems may occur in both systems, i Guess. Once possible solution is to use BrickController, "bypassing" the problem of the issue, but let's see.