WTF is Power beyond?
- Thread starter Flat 10
- Start date
Simon Chiles
DD Moderator
- Location
- Surrey/ Kent Border, UK
Modern hydraulic systems have a pressure and load sensing pump. Basically the hydraulic system is kept at continuous low pressure until the pump is told by the load sensing (LS) hydraulic line that it needs more pressure and flow, then it ramps them up to meet demand. As the pump only pumps oil on demand it saves power and stops the oil getting so hot and therefore it lasts longer before it's molecules break down.
Power beyond is just an extension of this on an implement. Again it allows the implement system to be at a low pressure until demand is sensed by the LS line.
he man
- Location
- Welshpool Powys
auld 3350s could do that with out all the kerfuffle,
- Location
- Huntingdon, UK
Very basically:
Imagine a system with lots of functions I.E. a bale chaser or something.
Normally you have a pressure pipe, a return pipe, and leave the spool in constant pumping. Then press a button on the implements control panel, and it'll work the spools on the implement and move a ram.
Now this uses quite a bit of power - when chasing, if you knock the spool out when accelerating you can feel the difference) it also heats up the oil. To overcome this you can manually flip the lever back to neutral when the implement doesnt need oil.
Power beyond uses a 3rd pipe, and effectively automates this process, so the tractor is only pumping when it needs too.
Imagine a system with lots of functions I.E. a bale chaser or something.
Normally you have a pressure pipe, a return pipe, and leave the spool in constant pumping. Then press a button on the implements control panel, and it'll work the spools on the implement and move a ram.
Now this uses quite a bit of power - when chasing, if you knock the spool out when accelerating you can feel the difference) it also heats up the oil. To overcome this you can manually flip the lever back to neutral when the implement doesnt need oil.
Power beyond uses a 3rd pipe, and effectively automates this process, so the tractor is only pumping when it needs too.
Simon Chiles
DD Moderator
- Location
- Surrey/ Kent Border, UK
Except the hydraulic system was kept at a constant high pressure. This is more sophisticated.
more to its detriment and the 3350s oil was perfectly cool and just sitting waiting for the action to happen.you will never under stand how jd achieved this master piece unless you have stripped a jd hydraulic pump.
- Location
- Hampshire
I have PB on my Deutz, but where do you connect the sensing pipe on the spool block?
Pint
Member
- Location
- East Sussex
Damn handy power beyond
Most 6400 masseys have the plumbing ready for this. My fergie has 4 spools which is not enough. So we fitted an extra two spools using the power beyond plumbing fitted to the tractor. The semi mounted plough I use needs four spools and if I'm using the stone graip on the front I need the other two, so it gives me six all together
Most 6400 masseys have the plumbing ready for this. My fergie has 4 spools which is not enough. So we fitted an extra two spools using the power beyond plumbing fitted to the tractor. The semi mounted plough I use needs four spools and if I'm using the stone graip on the front I need the other two, so it gives me six all together
- Location
- Huntingdon, UK
It may be blanked off.
Thanks @Andrew and @Simon Chiles. So power beyond is a name for load sensing spool valves? Or not quite that simple?
- Location
- South Devon
Its just a modern version of constant pumping and return.
Only modern hydraulic pumps have load sensing and only pump when oil is needed, so a L.S pipe is also needed.
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They use a closed centre pump I think same as my 6270 which is different to LS
Cowabunga
Member
- Location
- Ceredigion,Wales
Power Beyond is just a fancy name for a group of three dedicated coupling for implements that are to be used with remote spool valves or remote controlled flow of oil when both tractor and implement are equipped for use with Closed Centre, Load Sensing [CCLS] hydraulics. The two big couplings are self explanatory, one being the main flow and the other being a free-flow return to tank or sump. The third line, the smaller of the three, is the control or sensing line. All this does is convey a message through pressure and flow, so as to control the tractor pump. The tractor has a variable displacement, swash-plate, type pump where the full flow can be achieved at nearly idle speed if the control plate is commanded to do so by the sensing line. Or it can pump no oil, or any amount of oil that is needed, at any revs including flat out.
Open centre systems with fixed displacement pumps, on the other hand, displace [pump] a fixed volume of oil for every revolution of the pump, regardless of need. It follows therefore that full volume of oil pumped can only be achieved at full throttle, so that only half the volume of oil is pumped at 1000 engine revs as at 2000 engine revs.
I know the question was only about 'power-beyond' but I feel it is important to know how these systems work and the differences between them, in order to understand anything at all about them.
Open centre systems with fixed displacement pumps, on the other hand, displace [pump] a fixed volume of oil for every revolution of the pump, regardless of need. It follows therefore that full volume of oil pumped can only be achieved at full throttle, so that only half the volume of oil is pumped at 1000 engine revs as at 2000 engine revs.
I know the question was only about 'power-beyond' but I feel it is important to know how these systems work and the differences between them, in order to understand anything at all about them.
Cowabunga
Member
- Location
- Ceredigion,Wales
JD used a radial piston pump that used a cam to push the pistons but springs calibrated for the pressure pushing against the oil. As maximum pressure was achieved, the pistons moved away from the cam and stopped pumping. Very simple but relatively unsophisticated. The current system is far superior, but the old system was pretty-much unique to JD tractors while the modern CCLS systems are used by J Deere and most other brands of tractors above 125hp in their premium ranges.
Your MF6270 is either open centre, which is most likely on that model, or CCLS.
MF had a third system available in the UK for a while on their 6485 and above which made use of two fixed displacement gear pumps to supply closed centre spool valves. At least I assume that they are closed centre spool valves. This was called the 'twin-flow' option iirc. Very different to that used on the later 5400 tractors with the selectable second pump [blue button on console]. Quite why they bothered with that twin pump setup is anybody's guess, but I'll take a stab at it being a few Quid cheaper than the alternative CCLS system that they also offered.
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Simon Chiles
DD Moderator
- Location
- Surrey/ Kent Border, UK
Whilst closed centre hydraulics were unique to JD in the tractor world it was a common system on aircraft.
it is CCLS
sorry I meant its different from power beyond