Electric valve question

[ParkerFly]

I am needing a double acting electric solenoid valve to operate a hydraulic motor. When not operating the motor, I need the valve to be in float so that the motor can turn freely. I would prefer the valve not need electricity to stay in float, but to just be there naturally. I have found this valve and it looks like just what I need. Can some of you more knowledgeable folks take a look at it and tell me for sure?
Northman Fluid Power Hydraulic Directional Control Valve – 26.4 GPM, 4500 PSI, 3-Position, Double Solenoid, Tandem Center Spool, 12 Volt DC Solenoids, Model# SWH-G03-C6-D12-10 | Power Solenoid | Northern Tool + Equipment
If I'm looking at this right, P & T could be the two lines going to the motor, and it is naturally in float even with no electricity supplied. Am I right? Thanks,

Justin

 

[J_J]

That valve will work to let the hyd motor free wheel with no voltage. The P and T ports are connected with no voltage.

The work ports A and B go to the motor. Not the P and T

This valve will also work.

https://www.surpluscenter.com/item.asp?item=9-7774&catname=hydraulic

This type valve will provide instant hyd flow with no speed control. Otherwise full volume. Is that what you want?

 

[kennyd]

That valve linked will NOT work. Tandem Center means the work ports are blocked in neutral like you want for a double acting cylinder. You need a OPen Center valve.
P and T are the supply and return line and do not go to the motor. You will also need to order a sub plate with that.

 

[ParkerFly]

Thanks for pointing that out Kenny, that makes sense and I wasn't paying attention. So I'm guessing this valve would be the correct one for my application:
Northman Fluid Power Hydraulic Directional Control Valve – 26.4 GPM, 4500 PSI, 3-Position, Double Solenoid, Open Center Spool, 12 Volt DC Solenoids, Model# SWH-G03-C3-D12-10 | Power Solenoid | Northern Tool + Equipment

And JJ yes not worried about speed control, I would want it all or nothing once triggered anyway.

 

[J_J]

Different people use different terminology.

You probably want a valve that will shut off when the voltage is removed, and will let the motor free spin.

If it says motor spool, it should work.

Just about any valve can control a hyd motor, but it is the inertia of the load on the motor that will give problems. If you release the lever slowly, you can slow down a hyd motor. If the spools slam shut cutting off flow, things could go bad.


MOTOR SPOOL (Also referred to as free-flow). A spool designed to provide flow from “work” ports to “tank” when spool is in neutral position. This allows a motor to coast to a stop after the spool is placed in neutral position.

OPEN CENTER VALVE (Also referred to as tandem-center),

 

[oldnslo]

Terminology of valve spools is real confusing.

Motor spool: Work ports "A" & "B" are connected to "T" in the neutral position. "P" is blocked
Open center: All ports are connected in the neutral position. ( Also can be called Float)
Tandem center: "P & "T" are connected, "A" & "B" are blocked

Roy

 

[J_J]

The question, if it says motor spools, can the valve be tandem center? Motor spools let the fluid circulate, and prevent severe shock to the system.

 

[oldnslo]

The question, if it says motor spools, can the valve be tandem center? Motor spools let the fluid circulate, and prevent severe shook to the system.

Tandem center can be used for motors but they will NOT let the motor free wheel. Motor spools have the "A" & "B" ports connected to tank.

Tandem center allows the pump flow to pass through it from "P" to "T".

Roy

 

[J_J]

I stand corrected in post #2. Just about any valve can control a hyd motor, but the term motor spool should only be associated with free wheeling mode of a hyd motor. Just because a valve can allow the motor to turn, does not make is prudent to do so. If you are careful, you can get away with it. If you just let go the lever on a spring centered valve running a hyd motor, that is not motor spool, you invite trouble.