Passing Contact Switch Question

[ddoherty958]

Hi 

 

my local hardware store sells switches that are on-on and I was wondering if these will work in the system I have chosen for my layout; see the wiring diagram below. 

[Free At Last]

An on-on switch does not function the same as a passing contact switch which only gives a momentary pulse when it is thrown.

[Ray H]

You will need an (ON)-OFF-(ON) switch to use with Peco (and similar) point motors. The switch needs to be spring loaded and return to the central position automatically.

[ddoherty958]

1 minute ago, Ray H said:

You will need an (ON)-OFF-(ON) switch to use with Peco (and similar) point motors. The switch needs to be spring loaded and return to the central position automatically.

I’m using a Hornby point motor but I’m sure it’s all the same. Thank you, I’ll take a look in the store!

[steviesparx]

5 hours ago, Ray H said:

You will need an (ON)-OFF-(ON) switch to use with Peco (and similar) point motors. The switch needs to be spring loaded and return to the central position automatically.

Not necessarily so,

Peco's PL-26 as appears in the wiring diagram shown makes contact as it passes from one position to the other - Hornby's R044 does the same

https://www.Hornby.com/uk-en/passing-contact-switch.html

If you are not confident in electrical issues then stick with these switches which are specifically designed for the job - Hornby's comes with wires too.

Definitely DO NOT use the ON-ON switches you mention as these will supply current constantly to the motor and, at very least, burn it out.

[Sol]

While this page covers many things - work your way down & you will see some wiring diagrams using pushbuttons, toggles & it shows the Peco PL26

http://www.talkingelectronics.com/projects/CDU - overview/CDU - Overview.html

and of course there is the One-wire circuit

https://postimg.cc/bG569TC4

https://postimg.cc/gXr90Z5y

[Pete the Elaner]

6 hours ago, steviesparx said:

Not necessarily so,

Peco's PL-26 as appears in the wiring diagram shown makes contact as it passes from one position to the other - Hornby's R044 does the same

https://www.Hornby.com/uk-en/passing-contact-switch.html

If you are not confident in electrical issues then stick with these switches which are specifically designed for the job - Hornby's comes with wires too.

Definitely DO NOT use the ON-ON switches you mention as these will supply current constantly to the motor and, at very least, burn it out.

They may work in theory but I agree with Ray on this & having seen his layout working first hand (I live about half a mile away), it works very well.

Passing contact switches from Hornby & Peco are effectively off-on-off-on-off. Throwing the switch from one extent to the other will initially try to throw the point to the same direction to which it is set before throwing it the way you want it.

My own experience of SEEP motors is that they are gutless without a CDU, a brand new motor didn't come close to throwing a point. Peco's were better but vastly improved by a CDU so I highly recommend one. The CDU will discharge virtually immediately so when you throw a point  with a passing contact switch, the CDU discharges  when it passes the first contact, which throws the point the same way.

Unless you pause the lever in the centre off position, the CDU will not have recharged enough by the time is passes the contact which you want activated, so the motor may not throw.

Ray recommended centre off switches which are sprung loaded to return to their centre off position. These are better because they do not throw the point the  wrong way first, so the CDU discharge throws the point correctly. The disadvantage is you cannot see which way you set the point simply by looking at the lever's position.

[Free At Last]

7 hours ago, steviesparx said:

 

Peco's PL-26 as appears in the wiring diagram shown makes contact as it passes from one position to the other - Hornby's R044 does the same

 

 

30 minutes ago, Pete the Elaner said:

Passing contact switches from Hornby & Peco are effectively off-on-off-on-off. Throwing the switch from one extent to the other will initially try to throw the point to the same direction to which it is set before throwing it the way you want it.

My own experience of SEEP motors is that they are gutless without a CDU, a brand new motor didn't come close to throwing a point. Peco's were better but vastly improved by a CDU so I highly recommend one. The CDU will discharge virtually immediately so when you throw a point  with a passing contact switch, the CDU discharges  when it passes the first contact, which throws the point the same way.

Unless you pause the lever in the centre off position, the CDU will not have recharged enough by the time is passes the contact which you want activated, so the motor may not throw.

The PECO passing contact switch differs from the Hornby one in that the PECO switch only gives one pulse per throw.

There is a description here how it works http://www.talkingelectronics.com/projects/CDU - overview/CDU - Overview.html

Edited August 29, 2019 by Free At Last

[Pete the Elaner]

10 minutes ago, Free At Last said:

 

The PECO passing contact switch differs from the Hornby one in that the PECO switch only gives one pulse per throw.

I have read that on here before but I cannot find a diagram explaining how it can work.

I don't meant to be argumentative, but I was taught to not take anyone's word for anything without a reasonable explanation. It has made me find answers & understand things.

I will only be convinced when I see its internals, or a suitable explanation as to how it differs from the Hornby one (which I have taken apart many years ago).

[Free At Last]

1 minute ago, Pete the Elaner said:

I have read that on here before but I cannot find a diagram explaining how it can work.

I don't meant to be argumentative, but I was taught to not take anyone's word for anything without a reasonable explanation. It has made me find answers & understand things.

I will only be convinced when I see its internals, or a suitable explanation as to how it differs from the Hornby one (which I have taken apart many years ago).

See the link in my edited post.

[Pete the Elaner]

3 minutes ago, Free At Last said:

See the link in my edited post.

Excellent. I can see how that works. It sort of throws a hammer over at the contact & is a huge improvement over the Hornby switch.

[34theletterbetweenB&D]

But still vastly more expensive than two small brass woodscrews, which can be used to make contact studs on a layout diagram, and a wander lead to supply power to the studs.

[Pete the Elaner]

11 minutes ago, 34theletterbetweenB&D said:

But still vastly more expensive than two small brass woodscrews, which can be used to make contact studs on a layout diagram, and a wander lead to supply power to the studs.

I also prefer the idea of following the route with your finger (& probe) to set the points.

There is the argument that a lever frame is like a signal box...but only an older signal box, which were only built like that because you couldn't mount a huge lever in a mimic panel.

[Ray H]

Thanks for your support Pete.

 

The OP showed a diagram of a lever type switch but then went on to ask whether ON-ON switches - SPST or DPST presumably - would do the trick. I simply answered the question he raised about the ON-ON style switch, drawing his attention to the (ON)-OFF-(ON) style of switch.

 

I have no experience of either the Hornby or Peco style switches/levers although I have a vague recollection of taking a Tri-ang lever apart more years ago than I care to remember.

[Free At Last]

I like to use lever switches in a frame as I like to set a route into or/and out of a platform of my 6 platform terminus then return all levers to normal instead of leaving points randomly set.

The default 'all levers normal' is set for arrival to platform 6 and departure from platform 1.