3-Point Hitch Deere 110 TLB "power beyond" connection?

mert2828 · Oct 3, 2014

Longtime reader, first time question asker. Normally, I can find the answers to my questions thru searching this great site, but I've not found a clear answer as most power beyond questions deal with the loader.

Got a Deere 110, looking to add a 3 point hitch. If I'm going to do it, figure I might as well do TnT. Problem is, no rear remotes. But with the backhoe off, I assume I've got over 10gpm (I realize this number is debatable) of flow thru the "power beyond" quick couplers. So I should be able to connect a valve inline with these couplers. My question is deciding what type. Many times I've heard this referred to as a "power beyond" connection on this machine. So I tried to do my homework on power beyond vs open center. I think I have a pretty good understanding of the difference between the two, but one difference that I've noticed is that the power beyond will have a "return to tank" connection. I believe I've noticed 3 lines connecting the backhoe on an M59, but the 110 only has two lines, which makes me think the valve needs to be an open center instead of the power beyond, as it's normally referred. I assume the valve stack for the backhoe controls is a stack of open center valves, which is basically what I'm trying to accomplish, except 3 spools instead of 6/ 7, and ag couplers instead of backhoe cylinders. I prefer the open center valve because it doesn't require it's own return to tank. Could the backhoe stack be considered the last in the loop, which would allow for the use of an open center valve? Is this truely a power beyond connection?

This information will also be helpful when I finally make the time to add a log splitter to my collection, tapping into the same "power beyond" connection.

For what it's worth, looking to add this valve-
<http://www.surpluscenter.com/Hydraulics/Hydraulic-Valves/Directional-Control-Valves/3-SPOOL-25-GPM-JOYSTICK-LOADER-VALVE-W-GRAPPLE-9-8217.axd>
Control the Tnt with the joysitck, implement cylinders with the remaining spool. Seems like an ideal setup.

Zebrafive · Oct 3, 2014

First your tractor has an open center system, not closed, so you need open center valves.
VERY basically an open center system; the pump is fixed, constant displacement, so valves MUST have an open center.
A two hose system has the valves in SERIES. Pressure IN (inlet) to the first valve. OUT from first valve to inlet second valve. Repeats as many valves as the system has. OUT from last valve to tank.
With three hoses you have a PARALLEL system. BASICALLY; each valve has series and parallel connection for pressure IN and two OUTS to tank port. One OUT is the same a series and goes to the next valve. The other OUT goes back to tank. This way if one valve is used it's return full is directed to tank rather than the next valve. The last valve will have it OUT connection return to tank just like a series system, plus it will have OUT for just that valve. There could be extra passages in a stacked valve set rather than individual returns from each valve. So one hose would be pressure, second hose would be return to tank (same as series) from last valve, third hose would be return(s) from each valve to tank (from first or last valve depending how they are internally plumbed).

With a series system when a valve is operated ALL flow goes to that valve, then its return flow goes to the down stream valves.
With a parallel system all valves have flow even when another valve is operated. If more than one valve is operated the valve that has the lightest load will operate first, until it's load equals any other valve's (being used) load, then both will operate together.

mert2828 · Oct 3, 2014

Thanks Zebra. For the most part, you've confirmed what I was thinking....but for clarification, you're saying there are two different forms of open center plumbling, series and parallel. I understand how the two work, but the parallel version sounds a lot like a power beyond circuit.

With that said, since there are only two connections for the backhoe, it sounds like the 110's plumbing is a series plumbed, open center system. And if that's true, then the rear hydraulic connection is actually a simple connection point for open center valve(s). Which would mean this is not a "power beyond" connection as it has been called. Would you agree?

kennyd · Oct 3, 2014

mert2828 said:
Thanks Zebra. For the most part, you've confirmed what I was thinking....but for clarification, you're saying there are two different forms of open center plumbling, series and parallel. I understand how the two work, but the parallel version sounds a lot like a power beyond circuit.

With that said, since there are only two connections for the backhoe, it sounds like the 110's plumbing is a series plumbed, open center system. And if that's true, then the rear hydraulic connection is actually a simple connection point for open center valve(s). Which would mean this is not a "power beyond" connection as it has been called. Would you agree?

Since the BH valve is the last the chain when attached, it does not have the PB connection. So while technically you are correct, for simplicity sake the lines are just called power beyond. You can certainly plumb in a open center valve set there to operate your TnT setup.