I am about to do my first encoder battery replacement, on a Kawasaki BX130X. I have saved home positions and encoder values.
In the manual, it says to turn the controller off before replacing the battery. I just want to confirm that that is indeed the right thing to do, as for many other robots it says to keep the controller on when replacing the battery. How does it maintain the encoder values if the controller is off, and the battery is (temporarily) removed? Is there a backup battery?
I am about to do my first encoder battery replacement, on a Kawasaki BX130X. I have saved home positions and encoder values.
Always a wise move.........
In the manual, it says to turn the controller off before replacing the battery. I just want to confirm that that is indeed the right thing to do, as for many other robots it says to keep the controller on when replacing the battery. How does it maintain the encoder values if the controller is off, and the battery is (temporarily) removed? Is there a backup battery?
Each encoder has a large capacitor built in which remains charged for approx. 30 mins after power disconnection and battery removal.
So:
- Power down.
- Remove the battery cover (2 screws).
- Battery is zippy clipped to cover.
- Disconnect the old battery and connect the new one.
- Remove zippy for old battery and rezip the new battery to the cover.
- Re-attach the cover to rear plate again.
- Power up - Nothing should have changed,, no errors, should be ready to go again.
5 min job from start to finish.
So as long as you replace it within the recommend period of 30mins disconnection, you'll be golden.
The main reason for power off is due to older arms required the complete rear plate needed to be removed, exposing personnel to hazardous voltages and on very rare occasions some transients fly around and spike the encoders or mis alignment of the battery connector and ground the battery by accident.
Best follow and apply good electrical working practices though as 'you touched it last' remember.
It is generally recommended to replace the battery while the robot is powered on. If you know how to perform robot zeroing settings and there is no precise teaching data stored, it may not be a concern. However, if this is not the case, the encoder data could be lost at the moment of battery replacement. Therefore, it is advised to replace the battery with the power on.
It is generally recommended to replace the battery while the robot is powered on. If you know how to perform robot zeroing settings and there is no precise teaching data stored, it may not be a concern. However, if this is not the case, the encoder data could be lost at the moment of battery replacement. Therefore, it is advised to replace the battery with the power on.
Incorrect, where in the manual does it state this to recommend not to power off?
You are supplying an opinion based on your own working practices and NOT what is clearly stated in the manual AND posted at the top this thread.
If zeroing data is lost during replacement, then you are not following the procedures or there is an unknown issue within the encoder assembly.
Incorrect, where in the manual does it state this to recommend not to power off?
You are supplying an opinion based on your own working practices and NOT what is clearly stated in the manual AND posted at the top this thread.If zeroing data is lost during replacement, then you are not following the procedures or there is an unknown issue within the encoder assembly.
You're partially correct. The manual does indeed instruct to turn off the power. However, it also states that if the encoder data changes, you must perform zeroing again. If there is an engineer who fully understands the zeroing process, I also recommend turning off the power. But such engineers are not always present in the factory. The reason I suggested proceeding with the power on is to prevent potential data loss. I've carried out this method with many robots while keeping the power on, and it has never caused any issues. That's why I recommend this approach.
Well I'm not getting into a debate on who is right and wrong.
We have no idea about your cell safety measures, application or working environment and so following the OEM documentation is the correct and SAFE approach, even though it is a 5 min task, it carries risk.
Any maintenance works that require working within the robots working envelope should be suitably assessed and measures put in place to ensure robot motion is prohibited at all times.
When you are in a cell and behind a robot, you may not be visible to others.
Someone could accidently just start the system if suitable safety measures are not in place.
Just to further add to Kawasaki documentation if you are unsure of what to do now:
- Ask your company safety officer about your company policy regarding maintenance.
- Your company policy may have specific procedures regarding cell entry and LOTO.
- Usually a company has these procedures to safeguard employee safety for maintenance.
- If this is not applicable, inform a colleague where you are working at least.
- Ensure ALL safety interlocks are in place (LOTO) where you can.
- Double up and turn the controller into teach mode and take the key with you perhaps.
- Maybe take the teach pendant in so you have access to an emergency stop.
Whatever measures you can apply to prohibit motion whilst working inside the robot's working envelope is the safest way to work and gets you and your colleagues back home to your families after a successful day.
Stay safe out there people.
Here's a little tip for those who are worried about turning off the power while doing the procedure and want to take an extra precautionary step.
If your robot layout permits, kill the motion code and send the robot to it's HOME location where all joints are at zero before turning the power off and starting the procedure. Just remember the small robots usually stand up straight in the air and the bigger robots makes the L shape.
That way if anything goes wrong or doesn't go to plan it's super easy to check or set the robot zero since it's already on the witness marks.
Just note old robots might have a bit of brake wear and the robot might move a small amount when the brakes engage.
Here's a little tip for those who are worried about turning off the power while doing the procedure and want to take an extra precautionary step.
If your robot layout permits, kill the motion code and send the robot to it's HOME location where all joints are at zero before turning the power off and starting the procedure. Just remember the small robots usually stand up straight in the air and the bigger robots makes the L shape.
That way if anything goes wrong or doesn't go to plan it's super easy to check or set the robot zero since it's already on the witness marks.
Just note old robots might have a bit of brake wear and the robot might move a small amount when the brakes engage.
I agree with this method. Some small robots extend their arms upward rather than at a right angle.
