"CLICK" SOUND OF THE ROBOT

dhyan

Dear All,

By the end of year 2010 the ABB Robot has a new "feature" that I didn't find on the older Robot:
If the execution status is running and the motor status is Motor ON, but Robot doesn't do anything movement for few minutes,
then there is a "click" sound on the Robot.
Can you tell me, what it is?
I just think that the sound is occured because the main breaker of the motor servo becomes turning off although the motor status that showed on TPU is still on "Motor ON".
May be it is for saving the life time of the motor servo.

When I use the Robot (IRB 4600) for Pick and Place application,

Case-1:
Robot waits the "bottle is ready to be picked" above the bottle conveyor for more than 5 minutes,
so there is a "click" sound.
When the bottle is ready, Robot will move to pick the bottle, then suddenly "The Error 50204 Motion Supervision" is occured.

Case-2:
Robot waits the "bottle is ready to be picked" above the bottle conveyor for about 2 minutes (less than 5 minutes),
so there is no "click" sound.
When the bottle is ready, Robot will move to pick the bottle, then Robot can pick the bottle successfully and "The Error 50204 Motion Supervision" is not occured.

By comparing that 2 cases above, I conclude that when the "click" sound has been occured,
then it means that the torque limitation of the robot becomes decrease.

is my conclution right?

Best Regard

Dhyan

osku

Hi

 

The click sound comes when the brakes in the servo motors are activated. The brake feature has been there for many years, but the activation time has been longer before. As you wrote, end of year 2010 (maybe a bit earlier) this time has been reduced by default and now it's 120 seconds. So if there is no movement in 120 seconds the brakes will be activated to save some energy and also to increase the motor life time. This value can be changed under the Motion parameters - Motion Planner - (Used motion planner) - Brake On Time.

 

It sounds to me that in your case you might have some problems with releasing the brake. If the brake is not released properly, it will cause extra load to the motor and therefore cause the motion supervision error. I suggest you to contact your local ABB service representative and they could check the motor and the brake. Also I think it would be good to check if the brake on time value could be optimized. If the robot usually waits new job for 5 minutes, then it would be good to set the brake on time value for example to 10 minutes. This way you could avoid unnecessary brake activations.

 

-Osku 

dhyan

Dear Osku

        Wow, you give me clearly explanation, wonderful.
I appreciate it to much. Thank you for your answer. Now i have a solution for my problem.

Regards

Dhyan Wicaksono

irobot

Hi, osku

I have a question:

while the brakes activated , whether  the power of the motors are cut off at the same time ?
dhyan said that "although the motor status that showed on TPU is still on "Motor ON"."

thanks

osku

Hi

 

Yes the power of the motors are cut off at the same time. This is done to increase the motor life time and to save energy. MotorOn system output stays high and also Motor On status is visible on the TPU. This is because robot is able to "recover" from this situation automatically - robot will energize the motors automatically when next move instruction is executed.

 

-Osku