Controlling Point Motors

[Andy Lock]

I will be using an NCE Powercab to control my layout. It's a rabbit-warren style 5 feet by 2.5 feet.

I understand that I'll be able to control the points using the Accy button on the Powercab.

Can someone tell me what I will to purchase in order to achieve this, I'm probably going to use the SEEP PM-1 point motors.

Thanks  :)

[Diane Tape]

This is what use, reasonably priced easy to set up and works well.

https://www.digikeijs.com/en/dr4018-16-channel-switch-decoder.html

[Andy Lock]

Thanks Diane, I'll have a look at them. I suspect YouTube may have to be consulted to find out how to fit them 😀😀

[B.Meldon]

Be aware that this unit will only run one seep/peco style motor per output and it doesn't support using a CDU. Personally I would avoid the traditional solenoid motors and I use these https://www.dcctrainautomation.co.uk/mp1-point-switch.html as they are much more reliable and include a proper, reliable SPDT switch for the frog polarity. The also provide a nice prototypical slow motor action and hold the blade in position.


You can use the DR4018 shown above on Preset 6 to run them.

I would dispute the reliability of solenoid point motors! I have been using the Peco solenoid point motors on layouts for over 40 years now and in that time I have only had one fail with a broken pin, and that was the older type that had thinner pins. Once the motor and the frog polarity switches are adjusted correctly relative to the point and are properly secured I have found these are very reliable indeed I even have one layout that has automated passing loops that have points that have switched countless thousands of times over the years with no problems at all. (In this case each point has two peco accessory switches, one on top of the other, the second one required for the signalling and automation etc.)

It also should be noted that you can wire solunoid point motors in a way that each one has a 2200uf (60p) capacitor on each coil and then works from a SPDT (two way) switch. (Not a passing contact switch.) There is then no need for a CDU.

However perhaps these type of 'old school', simple and reliable methods of point opperation are not so good if you need everything DCC!

Brian Meldon

[B.Meldon]

Brian,


I don't think you are using DCC or a DR4018 as the accessory decoder?


These are very relevant facts that affect the choice of motor and implementation.

That is correct, I do not use DCC, but that does not make solenoid point motors unreliable.
Perhaps it is the switching of solenoid point motors with DCC that is unreliable, not the actual motors that are at fault in any way?

Brian Meldon

[Graeme Dunbar]

I would not go so far as say "fundamentally wrong". There are DCC accessory decoders for use with solenoid point actuators such as this offering from Lenz.
https://www.aandhmodels.co.uk/lenz-ls150-accessory-decoder-1062-c.asp

Also with DCC boosters of 10 A or so being fairly common, it is not exactly "low current". However using a separate power supply for point switching DCC accessory decoders and taking only the DCC commands from DCC is often recommended.

Agreed, solenoid actuators are less popular and the older low resistance ones even less so, but they are "fundamentally" part of track systems such as Kato Unitrack. Likewise other types are probably a good idea for new layouts, especially in the scenic areas where slow-motion actuators would look good.

[B.Meldon]

Perhaps the original post that stated that solenoid point motors were 'unreliable' should have just stated that they are not suitable for DCC use because they take too much power. 

I guess it is just one more reason why it is difficult to convert a DC layout to DCC unless you planned to do so during construction.

In regard to slow motion point motors in reality almost all narrow-gauge points are switched very quickly. In many cases the point leavers have to be pulled quickly or they do not go over! Some have weighted leavers that again make the point blade move very fast, hardly any use electrical motors and even those that do operate at some speed.
So, I would argue that quick moving point blades are just as realistic on a narrow gauge layout, if not more so than slow moving point blades.