I read That it can be also used in Ethercat with EK1100 for I/O commands even it looks so compact that I cannot imagine where these Beckhoff modules can be placed
i just installed a KRC5. The EK1100 is mounted in the top half of the enclosure. That part is empty when you only have just the 6-axis robot. if you have more axis i suppose the EK1100 has to be mounted externally, but i have no experience with that.
i switched from KRC2 directly to KRC5, i skipped the KRC4 completely. My biggest problem was workvisual, but that was all down to lack of knowledge. Since KRC4 is configured the same i don't think you will have much problems.
Did a couple of KRC5 past year, and I do like them.
Like:
- The dual/triple/quad cab, way less footprint for 3 robots.
- The option for the quad-KLI port, less need for external switches
- Less accu's/batteries
Less like:
- With the KRC5, all motor cables you have to bring into the cabinet and connect to the robot with the little connectors. We had issues that the Mastering Switch sensor was tripping due to elektrical interferance, caused by badly wiring the cables inside of the KRC5 cab. Not properly seperating power from data cables. That was no issue with KRC4, since you just plugged the big connectors into the controller baseplate, and did not have to bother with the internals of the cabinet.
- Recent project we needed the build-in transformer for France, was not ready/released yet. So we needed to add our own massive transformer in our control panel.
- Not sure if this was an issue with KRC4, i think not since i never encoutered the issue. With external axis, you need to connect the brake connector seperatly from the motor connector to the controller. So with 2 external axis, the mechanics cross-connected the brake and motor cables. Took some time to figure that out...
Attention points:
- The additional door on the side of the cabinet caused some issues at the beginning, since you need to be able to access it. So no placing fences, other stuff next to it where the door rotates.
- In the past we had 3 KRC4's, next to each other, all with smartpad holder. To store the smartpad, now with 3 robots in 1 cabinet. There are only mounting holes for 1 smartpad holder. So on some projects we had to make something to put the other smartpad holders, so the smartpads were fixed.
- In the beginning of the KRC5, we had a couple of robots coming from the KUKA factory, that were not properly configured, and could not be jogged in out-of-box state. Had to connect via WorkVisual and configure the robot type, since it had some Generic-x-axis robot type. Did not see this issue anymore last year.
- Not sure if this was an issue with KRC4, i think not since i never encoutered the issue. With external axis, you need to connect the brake connector seperatly from the motor connector to the controller.
Not anything I ever ran into on KRC4 -- the brake wiring was always part of the motor cable. The motor cable ran to the KRC, the resolver cable ran to the RDC.
- In the beginning of the KRC5, we had a couple of robots coming from the KUKA factory, that were not properly configured, and could not be jogged in out-of-box state. Had to connect via WorkVisual and configure the robot type, since it had some Generic-x-axis robot type. Did not see this issue anymore last year.
Ah, yeah. I have had that with KRC4s, generally on the first few robots after a major hardware or KSS version change. It seems like there's always a bit of lag before all the factory configurators get updated 100%.
- In the beginning of the KRC5, we had a couple of robots coming from the KUKA factory, that were not properly configured, and could not be jogged in out-of-box state. Had to connect via WorkVisual and configure the robot type, since it had some Generic-x-axis robot type. Did not see this issue anymore last year.
Last three times it was always like that, especially the systems with more axis
In general, krc5 are nice, required a bit more work with cabling, yes, and adding additional axis - one of them with 4 additional axis and it was a bit of a mess 
as you need one more RDC (two were provided) - of course not configured in the factory
Will be more expensive than krc4s aftermarket - that is for sure
No issues with them for about 2years i recall, so it will show in the future
You might want to visit the product presentation that lists all changes for C5 here or here.
In general, there are some older robots not available on the KR C5 and some newer ones not available on the older KR C4. However the KR C4 is not going to be around for much longer (as for new robots).
Pretty new, the next generation (KR C5-2) has already been revealed.
New OS, New Engineering (WoV Successor) and new Controllers (starting with micro)
