Point motor problems (insufficient voltage to move points?)

[MC123]

Hello,

 

I have a small DC N-gauge layout and I'm trying to wire up my first point motor. The wiring seems fine and the point motor moves in both directions when I flick the toggle switch *until* I connect the point motor to the points and then it doesn't have sufficient power to actually move the points. It buzzes but that's it.

 

I'm using:

 

- Gaugemaster WM1 transformer which provides 16 V AC

- 24 strand speaker wire through a simple toggle switch (no length of wire is more than about 1.5m) 

- I've tried a Peco surface point motor and a SEEP motor (same problem with both)

- I've tried 2 different sets of points (same problem with both)

 

When I take a reading with my voltmeter at the end of 1m of wire it shows that the WM1 is delivering around 20 V. So it doesn't seem to be the quality of the wire itself that's the problem.

 

However, when I test the voltage on the wires to the switch when I flick the switch it only reads about 4.5v. I'm wondering why that is. Could it be that the switch is faulty and somehow lowering the voltage that flows though it?

 

Any thoughts are appreciated. I'm afraid I'm not great with electrics though I did have a 00 gauge layout a few years ago and successfully wired up all the points!

 

Matt

[Nigelcliffe]

The Gaugemaster WM1 is a pathetically low current device - perhaps 0.75A at most, maybe only 0.5A.  

 

Most solenoid motors need several amps to move them, though it depends which version of motors are used (Peco make several different ones).  

 

Solution:  either need a capacitor discharge unit (which stores up power over a few seconds, then sends it in a big "umph" in one go), or a higher current power supply.   

 

 

- Nigel

[BoD]

Most probably as Nigel says but also

 

a) check that the simple toggle switches that you are using are ‘centre off’  and return to centre as solenoids do not like having a current continuously supplied and would not work if you decided to incorporate the capacitor discharge unit.

b) take care fitting the point motor in line with the movement of the tie bar of the point.  Seep motors are particularly prone to not working if they are out if alignment. 

[Jeff Smith]

You may need to remove the spring although this may also give you problems if the point motor does not hold the point blades hard in contact with the stock rails - especially if relying on the point blade contact for electrical continuity.

[Nigelcliffe]

6 hours ago, Jeff Smith said:

You may need to remove the spring although this may also give you problems if the point motor does not hold the point blades hard in contact with the stock rails - especially if relying on the point blade contact for electrical continuity.

 

BAD idea on standard N turnouts, operated by a solenoid motor (Peco, Seep, etc.).   Remove the spring, and there is nothing to hold the blades in position.  

 

Removing springs only makes sense if using a motor which provides positive pressure at end of travel with the power removed.  

 

 

- Nigel

[Jeff Smith]

Yes, sort of what I said 🤔

[MC123]

Many thanks for the comments. I've ordered a capacitor discharge unit so hopefully that will do the trick.

 

Matt

[MC123]

Just to confirm that a capacitor discharge unit has completely solved the problem I described above. Many thanks Nigel.

 

Matt