UR5 CB3 Turns On, But Won't Start

Hey all,

I am a teacher in Wisconsin using a UR5 with my machining and automation classes. I’ve had the robot for over three years now with no issues.

Today during my 1st hour class, the robot ran fine. The students shut it down when they were done with their project. I was supervising and everything seemed to be normal during operation.

I had a group of students during 2nd hour that wanted a demonstration on how to start their robot projects, so I powered on the robot at the pendant, took the e-stop off, and went to the initialization screen. I pressed the “on” button, but the “start” button remains greyed out. I have never seen this happen before.

I tried a restart, I checked to make sure the installation program is set to be the default program, and everything appears to be good there.

I am stumped, and figured I would make a post here while waiting to hear back from tech support.

Thanks for any advice!

Were you able to figure anything out on this?

This just happened to me with a CB3 UR3. I have tried everything. Some days it goes past the start up and initializes. Next power down and restart, it will not initialize?

Can you monitor the 48V supply from the Log tab right after initializing? Could be a faulty 48V power supply.
Alternatively, you can monitor all voltages and joints from the Low Level section.

I believe there’s a mechanical/electrical fault in the robot somewhere, and you could contact a distributor for fault-finding and repairing, if you’re not up for it yourself. :slight_smile:

Hello,
have you checked all the bus connections in the joints?
I had that issue with a UR3
Unplugging and plugging in could solve the issue with failed initiaisation.