Switch goes one way but not the other?

[dpcubed]

Ok, so just picked up a couple of the black eztrack turnouts from my LHS on Friday, the left hand switch will switch to one side when you use the little momentary press button, but not the other side. When investigating further it appears that its because the little magnetic solenoid on the bottom of the switch will pull the metal plate but wont push it. There is a bare fraction of movement when pressing to push the switch to opposite side of track, and when using the little manual peg on the switch everything moves perfectly.

Unfortunately, had a friend over this weekend and we were expanding the layout and rewiring a few things and he cut the green wire from the turnout to the switch and wired in more wire, so now that its been modified, cant return it to local hobby store.

Any ideas on how to get it to switch both ways? In advance of troubleshooting issues, I have tried it with the other switch from the right hand turnout,  and the right hand turnout and switch I picked up works perfectly together, but right hand switch with left hand turnout has same issue only switches one way.

[Joe Satnik]

Dear dp,

Any change in operation if you flip over the 3 prong plug at the turnout end?

Joe

[dpcubed]

Joe, at the turnout end, green 3 wire goes directly into the electromagnet box, there isnt a way to remove the wire. I have not disassembled the electromagnetic box yet but using voltmeter there is current hitting all three lines where they enter the box depending on which way your pressing the switch. Flipping the 3 prong plug at momentary switch end will cause it to have the same actions with opposite directions, IE if I have it one way and I press left, if Ive moved the turnout right manually, itll switch to left, if I then try to switch to right itll show the barest hint of movement but not actually switch. If I flip the plug over, same thing but now it switches when pressed to right, and hint of movement when pressed to left.

[Jhanecker2]

It sounds as if you have a defective solenoid  on one side of your turnout .  You might have a bad connection to the solenoid .  By the way who cuts wires when you  have connectors to unplug ?

[the Bach-man]

Dear Dp,
It could be that the linkage inside has become disengaged. Take off the bootom and take a look.
Good luck!
the Bach-man

[Joe Satnik]

Dear dp,

If  you know how to take resistance measurements with an Ohm-meter,

unplug the 3 pin connector and measure the resistance between pins 1-2, 2-3 and 1-3 on the end of the green wire. 

1-2 and 2-3 should be equal to each other and around 15 Ohms or so.  (Between 10 and 40 Ohms?)

1-3 should be very close to the sum of the first 2 readings.   

__coil____coil__
l          l           l
l          l           l
l          l           l
1         2          3

Let us know your readings.

Joe Satnik

[jward]

interesting. if you flip the wire connector over at the control box, the switch throws the opposite way from what it did before. this tells me that the soloniods are working the way they should, and that there is no bind in the mechanism.

therefore, the problem must be a defective control box. try connecting this switch to a different control box and see if it works.

[dpcubed]

Jward, no, it always only switches to the left on the turnout itself, flipping the connector over on the electric switch changes which one left or right causes it to go to left on turnout itself.


Jhanecker, there isnt really a pair of solenoids, its a single electromagnetic box with a tiny circuitboard on it, from what I can tell, green 3 wire runs directly into small board, then 3 copper wires loop around the box inside the shell numerous times creating the electromagnet, at a guess, the metal plate that slides inside the magnet is magnetized as well and depending on the poles of the electromagnet, determined by the current passing from the momentary switch, either pushes or pulls the metal plate which is linked to a polearm that actually moves the switch. As a side note I did say that he cut the wires on the wrong wire, wanted him to extend the wires from the electronic switch to the power box, not from the switch to the turnout(the bit that had spade connectors on it, I cut them off in order to use both switches on the bachmann grey box, and so just needed wire spliced on there). I had run to the store and came back to wrong wires cut.


Mr Bachmann, the linkage is attached properly, it throws the switch to one side, just not the other, and the manual switch does move the metal plate inside the electromagnet properly.


Joe Satnik, call me Dennis, and oddly the voltmeter returns 30 ohms for all three pairings, 1-2, 2-3, and 1-3.

[Jhanecker2]

The solenoid  is  an electromagnetic device with coils of wire  at  both ends in the turnout. When energized it pulls on the moving  member in the center of the coils depending upon which coil is energized . The plate in the center should not be permanently magnetic. It would interfere with the function of the solenoid. J2.

[Joe Satnik]

Dear Dennis,

Yes, that is...different...

Can you take the same resistance readings on your good turnout for a comparison?

A close-up picture of the circuit board would help.

Concerning the green wire repair, only the center pin (#2) needs to be connected to its original destination under the turnout.  1 and 3 may be swapped.     

Hope this helps.

Sincerely,

Joe Satnik

[dpcubed]

Joe,

Similar results from checking resistance on working turnout , pins 1-2 read 22-25 ohms, think maybe just couldnt get the leads in the plug well enough, pins 1-3 and 2-3 both read 30 ohms on the dot.


To get a close up of the circuitboard inside the electromagnet would require disassembling it, not sure I can reassemble it afterwards, looks like it is a very tight fit.

from what  I can see it looks like the print on the board is not actually serving any purpose because both the green wire coming in and copper wires running to the magnet are soldered together in pairs on top of the board, which would obviate the board serving any purpose beyond being a point to tie the wires together. Which means that its all down to whats being sent from the momentary switch determines what the electromagnet does.

[jward]

just out of curiosity, try tying the 1 and 3 contacts together, then reading between them and 2. your resistance should be about half or 15 ohms. if the reading doesn't change from 30, you have an open circuit on one of the coils. if it is down around zero, something is shorted.

resistance in series (1-3) adds. resistance in parallel (1&3-2) divides.

[dpcubed]

Jward, you were dead on ting pins 1-3 together and checking that with pin 2 hovers between 15-20. So the question is if all the resistances are right, why doesnt it switch?

[Joe Satnik]

Dear Dennis,

I located a good EZ-Track remote switch and measured its coil resistance with my DVOM.

Before the measurement, I set the meter to its lowest ohms setting,

then touched the 2 probes (black and red) together to get a "Zero Ohms" reading.

Usually there is a "zero" button (DVOM) or a zeroing knob (analog meter) to compensate for the resistance in the wires and other parts of the meter.  

If you can't zero, it usually means that the battery in the meter is either dying or dead, and has to be replaced.

Using thin metal leads from old 1/4 watt resistors to touch the internal pins of the 3 pin connector,

I read close to 19 Ohms pins 1-2 and 2-3,

and close to 38 Ohms pin 1-3 ,

which is what I expected and within the range I described earlier in this thread.  

If your wiring is modified away from stock, you would need to put it back to stock to get the resistance readings I got.  

If you have 2 (working, good) turnouts wired (correctly, not mis-wired) in parallel

(to try to throw both at the same time with the same momentary switch), your resistance readings should be halved.  

(= 9.5 Ohms 1-2 and 2-3, and 19 ohms 1-3). 

Atlas #56 is a screw terminal version of the Bachmann momentary switch.   

Hope this helps.

Sincerely,

Joe Satnik

Edit: modified momentary switch comment  

 



 

[Jerrys HO]

Joe
I run 2 turnout's with one switch with no problem. Ido have all my turnout's connected to one power pack.

Jerry