And now... electric problems

[Xylotica]

At last, I got Wall-E on a proper pedestal, made accessories to move it around with a Fenwick, and welded the mill fitting :

But now, as soon as I try to move the arm, it activates the breaker of the power outlet.
I already had similar trouble on another outlet, but at least I was able to move the arm.

I can hear the breaker shut off the power outlet as soon as I press one of the enabling switches on the back of the control panel.

Could it be the outlet's breaker which is too weak ?
I really hope it's not a nasty short-circuit hidden deep in the innards of the robot or the console...

Cheers,

[Johannes @ Robots in Architecture]

Hello,

We had the same thing happening when the circuit breaker was not properly dimensioned. I believe it has to be for 300mA while most common ones are 30mA.

Hope that helps!
Best,
Johannes

[Xylotica]

Thanks Johannes.

A 40€ breaker instead of a trip to the KUKA service center.... deal !

Cheers,

[Xylotica]

Oh boy... It turned out that I can't just replace the breaker because then the plug would not be suitable for other types of equipment in terms of human protection.
We are in the process of drawing a separate line from the counter, and we will wire the controller directly to that dedicated line with a 300 mA breaker.

I really wish that I had gotten this kind of information sooner ; it would have saved me a whole lot of time.
Maybe that would be something to add in a "Robot operator startup guide", or "Kuka for dummies".

I also noticed that there is a bolt with a grounding symbol on the robot base plate.
Should I connect this to the ground ? It feels awkward to have a tiny wire running next to those huge power lines...

Cheers,

[Johannes @ Robots in Architecture]

Hello,

I'm sorry to hear that - as I mentioned, the same happened to our (actually really good, electrician) if that is any consolation.
Generally I try to avoid giving any advice regarding the electrical or safety installation outside the robot, as that is not really my area of expertise and I don't want to endanger anyone with bad advise...!

Best,
Johannes

[Xylotica]

Now that I am on a 300mA breaker, it will not shut the juice down when I activate the robot motors, but occasionnaly, it does when I switch the controller on or off.
I even managed to activate the main breaker the other evening when shutting down the system.
It's a huge switch which is activated via a "pump" system to avoid arcs....Scary.

How can such a small robot give so much electric trouble ?
The electrician said something about induced currents ; I'm sure there are specific breakers out there who can handle and filter them out.

I know all this is a little mundane, but I'm sure that if we get to the bottom of this, it will help out other poor souls like me.

Cheers,

[Johannes @ Robots in Architecture]

Hello,

That is totally out of my area of expertise, but I find it very strange that the robot would trip the breaker when it is shutdown. Usually these problems occur when the motors are switched on and more power is drawn.
When you shut down the robot, it is decoupled from the entire power supply and uses the integrated buffer battery to safely power down the PC. From my limited understanding I don't really see how that could trip a breaker (unless maybe the power switch is mechanically faulty, shortening the wires).

Maybe try getting an electrician from a larger company that deals with commercial installations and machines. That makes a large difference compared to electricians who deal with residential installations.

Best,
Johannes

[Xylotica]

Thanks Johannes,

You are right, I need to find an electrician who is used to dealing with this type of machines.
The workshop where I installed the robot has huge machines and many welding machines, but there is no CNC at all.
Maybe this makes a big difference...

Cheers,