Let's go to the article now. Repairmen who have worked through KOMATSU excavators are probably familiar with these acronyms. O.L.S.S stands for O pen Center L oad S ensing S ystem C.L.S.S stands for C losed Central L oad S ensing S ystem. Previously, I thought that C.L.S.S was a more advanced method because it came after O.L.S.S. Specifically, PC200-5 uses O.L.S.S and PC200-6 and later switches to C.L.S.S. But when it comes to "big machines" like PC600-7, PC600-8 or even most recently with PC650LC-11 .... they still use the O.L.S.S system!! Then what is the difference between the two hydraulic control methods O.L.S.S and C.L.S.S of Mr. KOMATSU? And which one is better???
You get an A+, a steak and seafood dinner, and all the drinks you can handle if you and I ever meet.
Thanks for your goodness. Soon, when I have the opportunity to come to the United States. I will definitely call you.
I always thought the OLSS was a far better system. Far easier to understand, tune to operator preference and easier to troubleshoot. Only one orifice per pump to get plugged and cause issues and no leaky compensator valves. I suspect that to be one reason why it stayed in use on the big machines. The CLSS did give greater adaptability in that it used stack valve blocks. Want to run another implement, just add another valve section. All the correct passages were in place and you didn't have to try to engineer a way to stroke the pumps and maintain proportionality so everything else would work. Swiss Army knife for small to mid sized machines.
First, let's hear Mr. Komatsu himself talk about OLSS and CLSS. Of course, this is just a general statement, not a deeper one about the difference between these two hydraulic systems.
Isn't is odd that they are showing the compensators on the outlet flows of the valves when on the last job I did on an PC78, the compensators were on the inlet sides of the valves. I don't agree with their statements on the function and precise control for CLSS over OLSS either. When the Dash Six line came out, most of the operators complained that they didn't feel the power being put on the bucket. We had to put the two machines together and pull against each other with a scale in between to show the digging power was the same even though they couldn't feel it. It was also my feeling that all the different modes on the Dash 5 could make the machine work anyway you wanted. Problem in this country was that no one would even try to use them. Start the engine put the machine in top mode and go to work. Set a piece of pipe or a man hole and leave the setting where they were for digging and then complain about the machine not having the control they want. Most operators just went to slowing the engine down when needing really fine control. The last set of complaints I heard was that the Dash 8 and 10 models were too jerky and operators were liking the Deere/Hitachi line better.