Electric top and tilt

[RalphVa]

I tried looking up to find TnT online. All I found was a TBN discussion about it. You obsessed about electric having to be big and tough to be able to move the top link and side link while in motion. HELLO! When you adjust by hand, you don't do it in motion. Why expect an electric one to need to do this? We're gonna get them on electric tractors unless they go through silly shenanigans of using an electric motor to drive an HST. I'm sure some will be like this, but other electric tractors will have everything, including any (now) PTO implements with its own electric motor. All you'd do is connect an electric line when the implement is mounted.

What are there not any electric top and tilts out there?

Our driveway gate has an electric driver that runs it both ways, 12v.

 

[LS Tractor Owner]

Because electric are much slower, and a lot of the electric actuators are not very powerful. There are a few that might work, but most of the industrial rated ones are very, very large, both in length and diameter.

The use of TnT while "on the fly" is part of the reason to get them.... to be able to make adjustments while you are in process of working.

For example, using a back blade tilted from an extreme angle (say in a drainage ditch), but now that angle is too extreme for the end of the ditch where it 'flattens out'. You would make minor adjustments as you are moving flattening the angle of the blade.
Same principle with a box blade.... you might want to dig out material at the start, but then gradually spread / smooth at the end. Using the top link, this can be done easily while moving.

Hydraulics work very fast. Electric actuators are much different.... the stronger they are, the slower they move.

When electric tractors are the norm (probably not happening in the very near future) the manufacturers will probably design a different type of apparatus to accomplish the same task.

There is a big difference between electric and hydraulic functions....
Why don't we have electric brakes on our vehicles? Even on full electric cars there are conventional hydraulic brakes.

 

[s219]

Electric won't have enough guts to handle the actuation loads at any "feasible" voltages you'd be running on a tractor. I am sure if they ever have electric tractors, they will still have a hydraulic system driven by an electric motor. There are some things that hydraulics are superior for.

You absolutely want to adjust top and tilt on the fly for most applications where it's needed, like box blade use when grading. In fact, that is what elevates it to an art, since you can watch the box, material, and surface in realtime and make adjustments on the fly. It would not be very helpful if you could only make adjustments while stopped.

 

[mcfarmall]

The hydraulic system will have to be filled with windmill fluid because petroleum will be outlawed.

 

[Vigo327]

So as one of the (as far as i know) extremely few people to have any sort of electrically-powered top link (although not tilt), i'm still basically on the side of hydraulics.

The thing about hydraulic cylinders is that when the control valve for said circuit is closed (to the cylinder), the cylinder itself is essentially a solid object, and if you did push/pull on it extremely hard it is likely that a hose or fitting between the cylinder and valve will the failure point due to a pressure spike in the fluid. The hose and fitting are replaceable and relatively cheap. Hydraulic cylinders and circuits are essentially even stronger when sitting still than they are when moving and the forces move through the fluid.

On an electric linear actuator, there is a relatively small/weak electric motor hooked through a gear reduction 'transmission' to a threaded shaft. You can make an electric actuator as strong as a hydraulic cylinder, but even if you do, any impacts to the cylinder are NOT borne by fluid. Those forces go across machine threads and gear teeth in the very compact transmission. Electric actuators are just fine at moving 'dead' loads that don't really put any dynamic forces back into the actuator, but any time a 3pt implement bumps or snags over something or even just moves the 3pt up due to the contour of the terrain and then is allowed to fall back down to the previous height, you have a bunch of dynamic 'hits/judders/etc' going through whatever parts happen to be touching at the moment in the 'drivetrain' (these few threads, these few teeth etc) and the long term durability of it is suspect unless you upsize it well beyond the equivalent hydraulic setup in both physical size and cost. If you do manage to damage the drivetrain, it will be basically unrepairable, whereas the hydraulic system repair is usually just hoses, sometimes o-rings and lip seals inside the cylinder, or the rare worst case scenario of severely bending the cylinder rod which may still be individually replaceable without the cylinder being a 'total loss'.

My electric top link is actually just a hydraulic cylinder with an on-board self-contained pump/valve unit, called an electro-hydraulic actuator (EHA). The 'plumbing' has all the ease of an electric linear actuator because all you do is flip the polarity of two wires to make it extend and retract, but the 'impact/vibration resistance' is more in line with a regular old hydraulic cylinder.

Im not saying don't try it, im just saying pushing and pulling isn't the ENTIRETY of the job of your typical hydraulic cylinder, and resisting 'external' forces turns out to be something they're exceedingly good at. Linear actuators can do the pushing and pulling, but what you gain in ease of installation you might be trading away in long-term durability.

Here's a pic where you can see the electrohydraulic top link in profile at max extension, and another picture showing the same box blade tilted all the way forward (cylinder retracted).

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[oosik]

One of the MAIN reasons I got my FitRite hydraulic top link. I make adjustment on the go. You immediately see if the implement is working better or not. You can fine tune the implement down to a gnats eye lash - and never leave the tractor seat.

 

[ericm979]

Electric CUTS would need hydraulics in order to be backwards compatible with existing implements. Requiring customers to buy new implements would hurt sales, and the tractor company probably does not want to also be an implement company (though Ventrac and a few similar ones follow that model).

Having a hydraulic system means only one motor, not a multiple of them. You'd need four for a loader, two for top and tilt, etc. Hydraulics are cheaper than electric motors, especially electric motors with the same power and speed.

 

[ptsg]

The Farmtrac FT25G, an electric 26HP tractor, still uses the common hydraulic system. There is simply no other worthwhile way of doing it. It uses a 15kw electric motor for the drive and PTO and a 2.5 kw electric motor just for the hydraulic pump for all the hydraulic functions, steering, 3 point, remotes and loader.

 

[ddbackhoe]

The Farmtrac FT25G, an electric 26HP tractor, still uses the common hydraulic system. There is simply no other worthwhile way of doing it. It uses a 15kw electric motor for the drive and PTO and a 2.5 kw electric motor just for the hydraulic pump for all the hydraulic functions, steering, 3 point, remotes and loader.

Thanks for sharing that. Cute little thing, takes 8 hours to charge for 5-7 hours use. At least the info was easy to find, still havent found all that on the new Bobcat T7x (or price point). We havebeen bystepping the need to get offf of oil, but now the “powers that be” are trying to ram it home maybe a little too quick.

 

[ptsg]

Thanks for sharing that. Cute little thing, takes 8 hours to charge for 5-7 hours use. At least the info was easy to find, still havent found all that on the new Bobcat T7x (or price point). We havebeen bystepping the need to get offf of oil, but now the “powers that be” are trying to ram it home maybe a little too quick.

I agree that they're pushing the electric stuff too hard and too fast.

There is one of these electric Farmtrac that was delivered a couple months ago. The main focus of that farm is being sustainable and it's mostly a greenhouse farm. For that application, this is a great tractor. Very little noise and not exhaust fumes filling up the greenhouses. The guy also has plenty of solar power available, so charging costs will be minimal, and the way fuel prices are going now, savings are even higher.

As far as running time, I know people like to complain about that, but honestly, that's plenty for a tractor this size. A simple planning of the tasks can "fix" lots of the running time issues, if there is any.

A little video I found on the internet of it working: