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pogenestpogenest Posts: 2 Recruit
Hi Pros,

I haven’t found any topic where this question could fit in – I’m seeking contact with someone who has successfully rebuilt a UR control box for battery-powered operation.

We have build a UR-5 CB3.1 robot onto a MiR-100 mobile robot platform.

I used a SD-1000L-48 Power Supply and a  from Meanwell. on a CB3 .1 robot hardware.

After i made some modifications on the safety configuration, i reboot the UR and this error code:

C50A26: Voltage present on unpowered 48V power supply

I need to know the cause of this issue.


  • matthewd92matthewd92 Founding Pro, Tactile Sensor Beta Testers Posts: 1,267 Handy
    I have never done this so may be off base, but did you use the power relay from the robot?  It sounds like you are providing power to the 48V power supply before it is ready to receive it.  With the 120/220V installation there is a relay that is activated when you "power on" the controller, that turns on the 48V and starts sending voltage out to the arm and other ancillary systems.  For instance when you hit the e-stop the 48V power supply is killed thereby powering off the arm itself.

    I'm referring to this component.

    This was taken on a UR10 so you can see the lines feeding the two 48V power supplies, a UR5 would only have 1 set of wires going out to the power supply.  There is a 48V relay that is fed off of this power distribution block.

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