How 2 Reverse 12v Electric over Hydraulic pump

[jb889]

Just hooked up my used 12v electric over hydraulic pump to a cylinder. I couldn't figure out where to hook pos and negative cables but with some careful messing around I got the pump to start and the cylinder started extending. I never could get any reaction from the handheld remote which has up/down positions.

So, I bypassed the relay and hooked a direct positive and negative cable to each of the two posts. Pump worked. And then switched them thinking the motor might reverse directions (polarity). It doesn't, the cylinder just extended more.

So, I think the motor always runs the same direction. The pump body has a shaft which a hollow core "red thing" slides over. The "red thing" has 2 wires coming from it. One wire goes to one big post on the motor and the other wire goes into the harness connector for the up/down handheld remote. The handheld remote only has 3 wires going into it.

Please tell me what I am doing wrong. Does that "red thing" magnetically change fluid direction? Need more pics or info, let me know as I need to get this working asap.

 

[sandman2234]

I would think the pump would only push fluid one way, with gravity pushing the cylinder back down, unless it is a double action cylinder, which would work really well with the correct valve to change the direction (path) of the fluid.
David from jax

 

[jb889]

My cylinder is dual action. This powerpack should be a complete unit as it has the attached handheld remote with up/down. Whatever reverses the flow of fluid (the motor or the pump) is what I need to figure out. I don't believe it is the motor as I manually bypassed the relay as I explained before to reverse polarity. Cylinder extend in the same direction. I think the "red thing"(which is wired directly to the up/down switch) does something with the shaft on the pump but I haven't a clue what yet. The pump body has an OS logo for Oil Systems and says it was made in Italy but I can't find anything on the web. Haldex electrohydraulic powerpacks have two big posts on their motors but the relays are different looking.

 

[luscsmith]

If you want to reverse the motor, take the pump to a automotive starter shop and see if they can change the fields or find a differant motor for that pump.


Scott

 

[jb889]

okay, this elec over hydraulic pump was designed to go up/down in/out whatever - as the handheld remote says up/down. I am using this on a pickup mounted haybale spike I made integrated into my dual tube bumper. I need both cylinder in and cylinder out functions from the seat of my truck with the handheld remote in my hand. I need help either correctly wiring this powerpack or identifying why it is not switching direction and if a faulty part is to blame or my wiring. I have also tried grounding to the pump body as I saw a different brand pump grounded there. No luck. One direction movement is all I have.

 

[Redneck in training]

The motor is "serial motor". The stator and rotor are connected in series. Since relationship of the magnetic fields of rotor and stator is the same regardless of polarity of the current the motor will run in the same direction. To reverse it you need to reverse stator relative to rotor. But I don't think that is your problem. I would guess that the direction of the cylinder is controlled by a solenoid(s).
In example:
If there is only one solenoid it could work as follows:
Energized solenoid will move the cylinder in one direction and de-energized the opposite direction. Looking at the picture it looks like that the cylinder is either fully extended or fully retracted operated by a single solenoid. Try to energize the solenoid together with the motor to see if it reverses the direction.
If there are two solenoids:
One solenoid moves the cylinder in one direction while the other to opposite direction both de-energized lock the cylinder in place.

To check if the coil of the solenoid is operating. Energize it and put a screwdriver on the center of the coil if it generates magnetic field.

 

[Wayne County Hose]

Redneck summed it up pretty well. That is probably a Barnes or a Haldex unit, pretty common. The red thingy is a solenoid valve. No power to it, cylinder goes one way. With the coil energized, it magnetically moves a valve in the silver thingy which changes the direction of the fluid, no motor change of direction necessary.

Put the red thingy back on. Operate the unit to extend the cylinder, hold a screwdriver or anything else metal to the top part of the red thingy, where the nut goes. If it pulls off easily, it's not energized. Now try the other way, see if the coil is magnetized. If not, you either have a bad coil or no power to it. You have to figure out which.

Oooo, ooo. Just spotted it! The gold thingy on the top of the silver thingy? that's a manual release. Turn it to operate it.

 

[jb889]

Okay... Thanks Redneck in Training and Wayne County Hose. Unfortunately I am all spent to test what you both said tonight. My throat is too sore for any more of that cold air tonight. Will give it a go in the morning but I am understanding it more. I can picture that magnet magically attracting or repulsing some sort of spool valve. I must not forget that sometimes the simplest things will cause a problem (like maybe the handheld remote switch is out). I don't care what I have to do to hot wire this thing, I just want to do it from the cab of the truck when feeding the cows.

Thanks guys! and please post any other comments. I don't know jack about electrical unfortunately (or hydraulic, or...we will stop there).

 

[Redneck in training]

Hydraulic Power Units - DC

Look at this site.

 

[Redneck in training]

Here is an example of remote control wiring. I am guessing that if it is double acting unit either button starts the pump while only one operates the solenoid. If it is single acting unit then one buton operates the pump to extend the cylinder and the other operates the solenoid to lower the cylinder. In other words the cylinder retracts by external force when the solenoid is energized.