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Missouri | That may work most of the time. If you put a pressure gauge on the power beyond pressure line once, and watch the variations in pressure, you will see what I mean. I recently installed a system using power beyond on a late model deere (8245R IIRC). It had about 800 psi with no scv's in operation. With the fans operating, the system ran up to around 1500-1800psi. Operating other hydraulic functions (turning the steering wheel, raising/lowering planter/markers) caused the pressure to rise to 2800 psi. Momentary variations in drive speed occurred every time the controller had to compensate for pressure changes. The fluctuations were not dramatic, but they were noticeable. Installation of a load sense line brought it to a consistent 2800 psi, and eliminated flow variations when other hydraulic functions were utilized. On a tractor that's using PB because all 5 scv's are in use, usually it won't matter, because usually the load sense signal from one of those has already driven the pump to full pressure, but you're still talking about choosing what "usually" or "probably" works over the sure thing.
In another configuration, I omitted a load sense line, and did not have any problems. This particular tractor (8335R, IIRC) was operating a PWM controlled hydraulic drive motor on an SCV, and using power beyond with a Fasse valve to run a herbicide pump. In this particular instance, anytime the hydraulic drive SCV was engaged, the system was at full pressure. Lift circuits, and hydraulic drive circuits will typically drive a system to full pressure, but fan motors often times (but not always) will not.
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Can I run Hydraulic Planter Drives With Power Beyond?
