HI! Thank you for sharing this video, it is a very useful lesson, I like it a lot. I also have a question and if you could answer it that would be awesome, but if you don't feel like answering that's good too. So my question is: I've worked with several different machines, and I have an access to service manuals, them machines would have a very similar hydraulic system with LS signal relief, and to actually test the pump load sense differential and cut off pressure the manual would state something like "The hydraulic pump cut-off pressure is set higher than a function control load sense pressure reducing valve. A function control load sense pressure must be adjusted higher than hydraulic pump cut-off pressure to perform this test" so why is that, why the LS pressure has to be adjusted higher than cut off? Thank you
You have to override the load sense system and it's relief (load sense pressure reducing valve) so you can get the system up to the pump cutoff (pressure compensator spool adjustment) so you can set this. It's easily done by turning in the load sense spool all the way and deadheading a function. The pressure on the pump output will be the pressure compensating spool value. Set this, and then adjust your load sense spool back to low standby value. Deadhead a function again and adjust the load sense relief until you reach your max system pressure (based on LS relief value) and then you're done. Don't forget to go back an double check your pressures if you need to do a dynamic pressure adjustment on the LS spool for a delta pressure spec.
