Help: Electrical question on a Massey Ferguson 50e - Shuttleshift Solenoid

[Ronsii]

!!! Be careful where you start hooking 12 volt to on those solenoids!!!

I was just looking through vickers info for those types of valves and some of them have extra pins for switch feedback NOT for feeding the colis.

Also it looks like they have integral diodes for protection.

 

[franklin2]

I have found the diodes sometimes located inside the black square elbow plug that plugs onto the solenoids.

Be careful wiring this up, if you put the polarity wrong on the solenoid and they do have diodes, you will burn the diodes up. As was explained before, these are kickback diodes. They are installed backwards in the circuit. For the diode to conduct, the band on the diode is connected to the negative power. But you do not want it to conduct when 12v is applied, so it needs to be connected backwards with the + power to the band on the diode. The high voltage kickback generated be the coils when the power is removed is reverse polarity, so the diode clamps this and shorts it out.

As also was mentioned, you could probably live without the diodes for a time period, but the diodes will make your actuator switches last a lot longer. That high voltage kickback will spark on the switch contacts, and over time it shortens their life.

 

[Ronsii]

If one side is getting 12v on both leads that may be a feed back terminal and have something to do with why they wired in the relays(or if it is wired simply this would indicate a bad ground)... maybe a lockout so both cant energize at once...??? hard to say... I couldn't tell from your pics but is there 3 terminals on both sides of the f/r solenoid? can't find the exact p/n on eatons site so haven't founs a specific plug/wiring schedule yet.... but t does look like one of theose plug is NOT for powering the actual solenoid... it is strictly a feedback/position indicating feature that may be powering the relays somehow...

it would help f you could trace the wires and maybe draw a schematic of where they go... just the ones on the solenoid.

Oh, and also could you read the whole part number from the solenoid all I can see in the pic is the DG4V-3-6C... there should be some more stamped after that indicating other options relating to the wiring.

 

[Delmer]

Pretty sure the solenoids aren’t doing what they are supposed to do because one side is getting 12v across both terminals, while the opposing side is gets 12v on one terminal with the F pushed, and nothing with R pushed.

If I'm understanding you correctly, the voltage across both terminals means that neither of them is grounded, so that the coil is seeing 0 volts. Possibly the solenoid grounds are tied together (but not connected to ground) and the one side of the other coil is being backfed from ground. Since there is NOT power on the other side of that solenoid coil, it MAY be operating as it's seeing 12V. Test, test, test.

You did say this worked at some point recently, right?

 

[macgyver118]

Thanks for all the input, I have to head back to work and won’t be able to trace wires and draw diagram until the weekend. Also, I’m assuming the diodes are damaged since the voltage is so messed up. I’ll try to test that. Thanks again!

 

[hookedondiesel]

Here's a link to your solenoid, there should be a ground stud with a nut on the solenoid according to the diagram.When you follow the link, go to " 2d drawings " click there and a pdf of the solenoid will show up for download.
http://www.eatonpowersource.com/products/configure/industrial-valves/details/02-108045/

 

[Blade Miner]

Thanks for all the input, I have to head back to work and won’t be able to trace wires and draw diagram until the weekend. Also, I’m assuming the diodes are damaged since the voltage is so messed up. I’ll try to test that. Thanks again!

So how'd you fix the problem?

 

[56Chevy]

I have the same problem, but I can't see any of u guys pics, help?