KRC4 Display in sleep mode

Why?

Hmm,

The SmartPad runs a version of Windows CE and there are some display and power settings that you can play with, but do so at your own risk. I'm not willing to play with them on any of the robots we have.

To access, hook a keyboard up to the SmartPad. Turn the mode select key switch and hit the 'Windows' key on the keyboard. The WinCE taskbar should pop up on the bottom of the window. Tap in the lower right corner and you should have the option to display the desktop. This will be the WinCE desktop running directly on the SmartPad, not the RDP'd display of the Win7 session running on the controller. You should be able to find the settings there. Let us know what you find out!

Panic,

For one reason, screen burn. I've seen it with robots after not running for very long at all (a matter of months...) I'm sure there are other reasons.

Glad it worked out for you! I'm not familiar enough with the WinCE settings to speak intelligently on how the backlight settings might affect your application.

energy eh?

definitely but .... this is just a drop in the sea. smartpad draws ~10W. rest of the system draws 500-1000x that. there are so much bigger saving to be made just about anywhere else such as robot motions etc.

You could always press the white button and remove the hand pendant, or leave it on the unlogged-in state when in external.

Hi,

You are talking about saving energy with robot movements. I would be interested to know how this can be done?

thanks

well, did you do any math? without numbers, it is all just garbage and worth nothing...

yes, you can unplug smartPad... since smartPad draws up to 10W of power, and there are 24h in a day, that will be up to 240Wh a day assuming 24/7 operation. that is less than 1/4 of a kWh which costs $0.13. so by removing smartPad you are saving $0.03 per smartPad per day or about $0.0221 per smartPad in 17h (your average day) and you can expect total saving per day $0.0221*80 = $1.77 saving if all 80 robots are running without smartPads. in a month you may save this way up to $38.8 or so.

But this is If smartPad really draws max power of 10W. Probably brightness is not maxed out so this may dop to $25-30 per month.

Question is if this is the most reasonable place to save energy. It does not matter where the savings come from as long as you reduce power consumption.

now take a look at your robot motors. most of them are couple of kW in size. and robot has usually six of them. then there may be external axes too. when robot is decelerating, motors are working as generators and they are pumping energy back into intermediate circuit rising bus voltage. when that voltage exceeds a threshold, energy is dumped into ballast resistors. They burn this energy into heat. you can replace ballast circuit with fancy option that takes this energy and puts it back into power grid. Kuka does have it but i have never seen it installed on controllers i worked on.

so when ever robot decelerates, energy is wasted. Some of it may be recycled and used to power other axes if they are accelerating. And after deceleration, robot needs to start moving again for next motion, This means consuming energy from the mains. the more frequent and aggressive stop and go motions are, the more energy is wasted. Btw. ballast resistors are in banks of 1600W or 3200W on standard KRC4. they are not continuously radiating heat but they do it in pulses and one pulse they endure is much more than puny 10W from smartPad.

Every time there is a motion that should be but it is not approximated, robot stops and this adds about 1 sec in cycle time. but robot programs are usually very repetitive and cycle times are short... maybe 5-30sec. so even one such stop per process sequence, will be repeated hundreds of times an hour. so one single not optimised motion can cost you easily in a day, what smartPad would consume in a year. but many programs i see are far from optimal, there is a lot of aggressive and jerky motions. then multiply that by 80 robots and you can see that focusing on energy consumption of smartPad was poor strategy. yes it can add to savings but this is probably last place to look. there are other low hanging fruits to pick.

next you can reduce velocity slightly (or acceleration, or both). this too will increase cycle time but you get energy saving since robot will use less current. of course you can leave some motions fast but

do more than a slight reduction on certain path segments where robot does not need to move fast.

it is like driving the car, washing car may improve fuel economy but this is nothing compared to savings possible by moderating how aggressively you drive.

Quote from panic mode

Kuka does have it but i have never seen it installed on controllers i worked on.

Do you have any additional info about this, a quick search failed to provide any useful results.

panic mode

Hi,
Thank you, the things you explain are very interesting.

1. Do you know how to demonstrate that lowering the speed of robots consume less energy?

2. Do you have information about what you explain about kuka, to take advantage of the deceleration to create energy and be used again

could you answer me

thanks

1. Motor torque is proportional to current. More current is more torque. More current is also more energy consumed. And KRC has built in oscilloscope which can be used as a very detailed study tool.

2. As mentioned i have seen the article number and description of it, but never saw one. Call KUKA and ask them to dig it out. if i had some time, i could try digging through my portable drives but this is not worth my effort and certainly it is not something i can do now. Just ask KUKA, how much effort is that. besides, they will give you more up-to-date info. if this thing is not selling, it may as well be discontinued too.

would be very interested in analyzing the process with an oscilloscope. Should we install any program on the robot?