To20Chris
Platinum Member
Thanks, yes that would be useful. I'll try to find it - can you think of any good words to search on?
hydro pto hp loss?
- Thread starter TNCHRIS
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DAP
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Search on non-alphabetic characters like say ...
&!#(@*#$(#
or
words like .. idiot, booger eatin moron, arse
a$$, etc.
You'll find it. /forums/images/graemlins/blush.gif
&!#(@*#$(#
or
words like .. idiot, booger eatin moron, arse
a$$, etc.
You'll find it. /forums/images/graemlins/blush.gif
To20Chris
Platinum Member
Only if I'm lookin for the hydro/gear war posts, and who has time for that! /forums/images/graemlins/grin.gif I did find it:
How does HST work
There are multiple pumps in HST, which was my main error, and the pump is variable displacement, not the motor as I had assumed.
I think that means the power lost to the PTO in a hydrostatic tractor is due to the drag (pumping and friction) of the hydrostatic drive pump (and charge pump?) hanging on the output on the engine. Also, loads on the PTO should not cause heating of the hydraulic fluid any more than with a gear tractor.
Thanks for helping me figure it out!
How does HST work
There are multiple pumps in HST, which was my main error, and the pump is variable displacement, not the motor as I had assumed.
I think that means the power lost to the PTO in a hydrostatic tractor is due to the drag (pumping and friction) of the hydrostatic drive pump (and charge pump?) hanging on the output on the engine. Also, loads on the PTO should not cause heating of the hydraulic fluid any more than with a gear tractor.
Thanks for helping me figure it out!
jinman
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</font><font color="blue" class="small">( the pump is variable displacement, not the motor as I had assumed.
)</font>
Chris, like many things, there's always the exception. I don't know about other models, but the New Holland Class III CUTs (TC35D, TC40D, TC45D) all have displacement of both the HST pump and the motor. The pump's displacement is controlled by the HST pedals and the motor's displacement has two fixed positions controlled by an electrical solenoid.
These tractors use a switch on the FEL joystick (and a duplicate switch on the fender console) to control the motors displacement angle at 9° or 15°. Therefore, with your hand on the joystick, you can not only control the loader, but also change ranges/speeds in the tranny. If you don't have a FEL, the fender mounted switch will do the same thing.
This feature was one of the HUGE issues for me when I bought the NH.
)</font>
Chris, like many things, there's always the exception. I don't know about other models, but the New Holland Class III CUTs (TC35D, TC40D, TC45D) all have displacement of both the HST pump and the motor. The pump's displacement is controlled by the HST pedals and the motor's displacement has two fixed positions controlled by an electrical solenoid.
These tractors use a switch on the FEL joystick (and a duplicate switch on the fender console) to control the motors displacement angle at 9° or 15°. Therefore, with your hand on the joystick, you can not only control the loader, but also change ranges/speeds in the tranny. If you don't have a FEL, the fender mounted switch will do the same thing.
This feature was one of the HUGE issues for me when I bought the NH.
normde2001
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I can't imagine wasting even a minute of my retired life thinking about how much pto hp my tractor has and why.
To20Chris
Platinum Member
Well, I'm not retired, so right now I'm wasting someone else's time thinking about it! /forums/images/graemlins/grin.gif
rambler
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</font><font color="blue" class="small">( I can't imagine wasting even a minute of my retired life thinking about how much pto hp my tractor has and why. )</font>
That would change if you needed to use your pto and had to plan for how much hp & lifespan the tractor would offer you for the jobs you wanted it to do.
People on this issue divide into those who have the tractor for a hobby to have fun, or need the machine to do a job & get work done.
There is nothing wrong with either group. Just each has different needs, and that shows up _very_ clearly on the issue of which tranny to use. /forums/images/graemlins/smile.gif /forums/images/graemlins/smile.gif /forums/images/graemlins/smile.gif
Me, I can't imaging _not_ worrying about it, as that is an important needed feature of a tractor. But again, that is _me_ and my needs, and does not affect your use or needs. We can both go away happy, even tho we would have very different issues when shopping for a tractor. /forums/images/graemlins/smile.gif Neither is right or wrong. But can you see the other groups' need to know this? For them, it is important.
--->Paul
That would change if you needed to use your pto and had to plan for how much hp & lifespan the tractor would offer you for the jobs you wanted it to do.
People on this issue divide into those who have the tractor for a hobby to have fun, or need the machine to do a job & get work done.
There is nothing wrong with either group. Just each has different needs, and that shows up _very_ clearly on the issue of which tranny to use. /forums/images/graemlins/smile.gif /forums/images/graemlins/smile.gif /forums/images/graemlins/smile.gif
Me, I can't imaging _not_ worrying about it, as that is an important needed feature of a tractor. But again, that is _me_ and my needs, and does not affect your use or needs. We can both go away happy, even tho we would have very different issues when shopping for a tractor. /forums/images/graemlins/smile.gif Neither is right or wrong. But can you see the other groups' need to know this? For them, it is important.
--->Paul
