Best point motors for N gauge

[markwilson]

Please forgive me if this has been asked before, but I have spent some time searching the forum and don't think this is a repeat question (to my surprise).

My last layout used Peco PL-10E motors with PL-9 plates and a Gaugemaster CDU. All good, but that was DC and Insulfrog. This time, I'm going DCC and Electrofog/Unifrog though I think It's likely that the point motors will be DC operated - only the rolling stock will use DCC for now.

 

1. There are some really good posts about the need for an accessory switch (like this one) and I understand this now (thank you). What's not so clear to me is whether I can come up with a non-motorised frog polarity switching solution or whether I need to jump in with both feet and buy all my point motors and accessory switches right away (about 20 of them).
2. Then I'm trying to work out why I would use the Peco PL-15 over the cheaper PL-13s.
3. Finally, I understand that some motors have the accessory switch built in - what are the "best" point motors/accessory switches to use in N gauge.

 

Please, can anyone help me navigate this minefield? Easter holidays are coming up, which means track-laying opportunities, if I can get my order for motors, etc. in quickly!

 

Thanks in anticipation of your help, Mark

Edited March 23, 2021 by markwilson
Grammar

[Nigelcliffe]

Wiring of N-gauge points is a bit of a minefield of confusion, because people read stuff for Peco OO and assume the N items are the same, which isn't quite the case.    (There are other point suppliers, but keep them out of things for now).  

 

Peco N come in three broad types:  Insulfrog (plastic frog),  Electrofrog (metal frog) and the new Unifrog (metal frog).   

 

The Unifrog is wired like a OO turnout.  If you want it to work reliably, it needs power switching of the frog, but it can be left without the frog wired, and it behaves like an insulfrog turnout (ie. insulated bit in the middle).  

 

The Electrofrog is complex.   As supplied, power is switched to the frog by the blades, so arguably do nothing, add no wires.   
Various people advocate adding a second switch to change the frog, doubling up on the blade switch because the blade switch can sometimes be found to be unreliable.   

But, unless that second switch moves when the blades are mid-travel, you create a short circuit because one switch moved before the other.   That short can stop your DCC system momentarily.   

So, that then creates further modifications when extra insulation breaks are cut into the blade rails, and further bits of wiring are added.   In short, it gets very messy.   
Side-ways solution to this are electronic devices to switch the frog (so called "frog juicers" after the first well known product to work that way), with those the timing issue goes away.    

 

 

So, having introduced the minefield, pick your motor.   

 

There are solenoid motors, such as the Peco types discussed, and the well known SEEP motor.  Simple, work, but a bit brutal. 

 

There are motorised devices, such as Tortoise, Cobalt, and the MP1.   Their internals are different, but essentially a motor drives the tie bar over, and it stops moving automatically at end of travel.   All of these include a switch (or two) which can be used for frogs.  

 

There are servo motors, which have become popular because they're pretty cheap.   But, need to add in device to connect servo to tie bar (numerous designs and commercial products exist),  they need a bit of electronics to control their movement,  and also need to add something else for frog switching (again dozens of solutions). 

 

Any of the above can be controlled by conventional panel switch wiring ("DC wiring"), or could have further electronics added to control them with fewer wires, be it via DCC or another "control bus".  

 

 

Decide which rough route, then no doubt more specific information could be added.  

 

 

- Nigel

 

[markwilson]

That's really helpful - thanks @Nigelcliffe. I was tempted down the Peco route of least resistance, but will look again at the motorised devices because they should be more realistic, and include the switch... time for some YouTube watching, I think!

 

One thing I'm still not clear on (if I do go down the Peco route) is the difference between the PL-13 and PL-15 switches?

[warpy]

If I remember correctly Mark the PL13 is a single switch so works well if you just want to control one circuit that switches when the point moves. So would work well to flip the polarity to the frog OR to provide a feedback to say an LED panel. You can’t do both as you need separate circuits. They’re pretty simple to fix under the point and have proved pretty reliable for me. Think I’ve only replaced one or two. 

 

The significantly more expensive and very fiddly PL15 provides two separate switches in the same unit so you can flip the polarity of the frog AND provide a feedback to an LED. 
 

On Warphampton I have 54 point motors including the fiddle yard (crazy I know) and initially just wanted the LED circuit for my panel. I’d bought electrofrog points but decided to rely on the blade contact to drive the frog. So I went for the cheaper PL13 for all points simply to save money. I only used the PL15 on the 6 double / single slips I have where you have to have an electrical frog switch as a minimum. So I needed the twin accessory switch to drive the frog polarity and LED circuit. I’ll be honest they drove me mad as they’re quite fiddly in n gauge. You have to adjust the angle of the micro switch at each end so they just make / break contact and with n there isn’t a lot of throw. If you had a second pair of hands to help test as you adjust that would make it easier. But under a baseboard on your own was not always easy!

 

Having said that I did soon find blade contact alone wasn’t sufficiently good for electrical contact so running over points wasn’t brilliant. Eventually I decided to wire in a cheap 2nd micro switch (not much on eBay) for each point which was glued on top of the PL13. Retrospectively soldering feeds onto a ballasted point wasn’t the best and it was a little fiddly but it transformed the running and I don’t really notice the small solder joints near the frog and feed rails. Hopefully with the uni frog the wire is already there and you can do that more efficiently upfront. 
 

So my conclusion would be - definitely take the time to juice the frog rather than rely on blade contact. If you never see the need for a second circuit like Panel LEDs then I’m sure the PL13 would work well attached to a peco point motor. As mentioned I’ve never actually used those for the frog juicing as I’d already used them for the LED circuit.  If you need twin circuits then might be working looking at motors which include a twin accessory switch included, as the Peco point motor plus pl15 is not that cheap and is pretty fiddly. 
 

Hope that’s useful from what I did but give me a call if not or let me know if you want any photos. 

 

 

[Nigelcliffe]

8 hours ago, warpy said:

If I remember correctly Mark the PL13 is a single switch so works well if you just want to control one circuit that switches when the point moves. So would work well to flip the polarity to the frog OR to provide a feedback to say an LED panel. You can’t do both as you need separate circuits.  

 

 

You can "do both" with a DCC layout, it's trivial:    The switch swaps the track power to the frog.  Run the frog wire back to the panel, where it connects to two LEDs.  Those LEDs connect one to each side of the DCC track bus, and only one will illuminate. 

   

Whether its efficient wiring is another matter, because such feedback makes it three wires per turnout (but its the same wires with a turnout motor with two switches on it).  I'd be considering swapping to one of the numerous bi-directional control busses if that level of feedback were necessary.   OR, Designing a panel where the switches showed the turnout positions, and thus not needing the feedback from the point motor.  

 

 

 

[Gavin Liddiard]

I would avoid solenoid point motors. I replaced over 40 Peco solenoid motors and their clip on accessory switches on one of my club's layouts in 2019 due to their poor reliability. After looking at various options I found the MTB-MP1 point motor (sold by DCC Train Automation). I bought one to test and it worked really well.

It's a slow acting motorised point motor with an accessory contact switch built in (perfect for switching frogs). Control is by 3 wires. On my club layout we used the Digikeijs DR4018 accessory decoder on dcc but they can easily be switched by a spdt switch with a 12v supply. 

If you are building a conventional control panel and want led feedback on the point position, that is possible with this point motor. I found the blog posting of a Czeh modeller that has utilised the motor's wiring design to create led feedback without the need for an extra accessory switch: http://www.modulybrno.cz/ohlas-mp1

 

 

 

 

I have fitted five on a small n gauge test track and they work fine on their 3mm travel setting.

Like other motorised point motors you need to remove the detent spring from the Peco points as the point motor holds the point blades in the chosen direction.

 

I'm currently planning a large American N layout and I will be using these point motors. They might be more expensive than a solenoid motor and switch but they are much easier to fit and adjust and work so much better.

Edited March 24, 2021 by Gavin Liddiard

[warpy]

7 hours ago, Nigelcliffe said:

 

You can "do both" with a DCC layout, it's trivial:    The switch swaps the track power to the frog.  Run the frog wire back to the panel, where it connects to two LEDs.  Those LEDs connect one to each side of the DCC track bus, and only one will illuminate. 

   

Whether its efficient wiring is another matter, because such feedback makes it three wires per turnout (but its the same wires with a turnout motor with two switches on it).  I'd be considering swapping to one of the numerous bi-directional control busses if that level of feedback were necessary.   OR, Designing a panel where the switches showed the turnout positions, and thus not needing the feedback from the point motor.  

 

 

 

I think my approach could definitely simplified as I’ve basically got three sets of wiring under each point - the peco motor, the LeD feedback and the frog power switch. Metres and metres of wiring. 

 

At the time it was my first proper layout and the book I read (I didn’t really think to research the web resources 10-12 years ago, if there even was much out there) suggested best practise was to separate the DCC bus from all other circuits. Certainly with 54 point motors the fault finding is much easier when the DCC, LED feeds and point motors are all totally separate electrical circuits. 
 

Point taken though, if I had my time again I think there are simpler approaches particularly with more tech out there. 

[markwilson]

Thanks everyone for you comments. They have really helped me get my head around things.

 

Inspired by @Nigelcliffe's original response, I decided to look at motorised points. Cobalts and Tortoises look huge (and expensive) but the MP1 that @Gavin Liddiard mentioned is interesting and I've ordered one to try, especially as the combination of Peco PL-9,PL-10E and PL-15 adds up.

 

Fiinally, I thought some may be interested in the advice below, from Peco's technical advice service, re: their accessory switches:

 

"For N gauge turnouts it is best to use PL-15 switches as the switch positions can be adjusted to suit."

[Gavin Liddiard]

I think you'll be pleasantly surprised by the MP1 point motor. I found them very easy to fit and adjust.

I found that the ideal mounting screws and washers for these motors to be self tapping pan head 3/8" x 4gauge (Toolstation product code: 54859) with M3 steel washers that spread the force evenly over the mounting slots. I found that on the side opposite to the electrical connections I needed to file a flat on one side of the washer so that it would lie flat (I was mounting onto a 9mm plywood baseboard).

Edited March 25, 2021 by Gavin Liddiard

[markwilson]

I've been testing my MP1, before buying some more... and I'm really impressed. One thing I've been struggling with though is getting my head around the wiring (even with the instructions). I'm not using DCC for the points - only for the locomotives - the point motors will be controlled with manual toggle switches and a separate DC supply. Meanwhile, most of the online advice seems to relate to using a Digikeijs DR4018 accessory decoder.

 

I managed to work out the DC wiring with a 9V battery to test the motor but poking the Aux switch contacts with a multimeter isn't suggesting any activity. Can anyone advise please on what the wiring should be to polarise the frog on my Electrofrog/Unifrog points from the Aux switch on the motor, please? Is it track feeds +ve and -ve to f1 and f2, and frog wire to to Aux1?

 

 

(Ignore the colours on the wires - they were just what I had lying around - though I'm not sure which colours I should really be using, despite looking at the DCC Wiki suggestions - blue, yellow and white?).

[Nigelcliffe]

51 minutes ago, markwilson said:

 

I managed to work out the DC wiring with a 9V battery to test the motor but poking the Aux switch contacts with a multimeter isn't suggesting any activity. Can anyone advise please on what the wiring should be to polarise the frog on my Electrofrog/Unifrog points from the Aux switch on the motor, please? Is it track feeds +ve and -ve to f1 and f2, and frog wire to to Aux1?

 

 

 

The line diagram on the motor shows the switch arrangement, I'd expect the fat "bar" to correspond with the motor movement left-to-right. 
From the edge of the motor, the first two contacts are the track feeds, the third is the frog wire.   A meter set to resistance or continuity testing should show those changing when the motor moves from one position to the other.  

 

 

Wire colours should be "whatever standard you use on your layout that will be clear to you at a later date".  

 

 

- Nigel

 

[markwilson]

Thanks @Nigelcliffe - sometimes it just helps if someone confirms my thinking! And I was using my multimeter incorrectly, because I was reading voltage (oops). Thanks for the advice.