First time with point motors query

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Oranoco
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First time with point motors query

Postby Oranoco » Tue May 15, 2018 9:50 pm

I'm still tinkering away and fed up of traipsing round the board to flick the 2 extremeties points, I bit the bullet and ordered a couple of Peco point motors and some Hornby switches. Never needed to consider them before as my old board from my childhood was about 4'6" x 5'6" and my dad and I would sit at opposite sides of the board so all points were accessible, current board is 8' x 4'

Now I appreciate this might be a stupid question but can I wire the 2 motors to 1 switch as the points access the rear loop so will always be operated together anyway?

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alex3410
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Re: First time with point motors query

Postby alex3410 » Tue May 15, 2018 10:16 pm

Yes but you should probably look into getting a CDU - capacitor discharge unit.

Essentially what it does is builds up a store of power, then when you flip the switch it releases it in a burst - this is important because point motors need a good jolt to flip the switch correctly and if you’re flipping two points the power gets shared between them. Without the CDU it may not be enough to successfully flip both points at the same time

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Bufferstop
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Re: First time with point motors query

Postby Bufferstop » Tue May 15, 2018 11:24 pm

Ah! There's a problem with Hornby switches and CDUs. The Hornby switch fires both coils in sequence each time it's moved, so your CDU get partially discharged ineffectively firing the coil from the previous move first. The smaller Peco switches avoid this problem by a bit of clever mechanical design. Alternatively you can do it with push buttons, stud and probe, or sprung to centre switches.
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Oranoco
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Re: First time with point motors query

Postby Oranoco » Wed May 16, 2018 12:23 am

Ah cool, thank you. May need to wire it as 2 switches as an interim measure and add the CDU when I motorise some of the other less accessible points.
Last edited by Oranoco on Wed May 16, 2018 9:43 am, edited 1 time in total.

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Flashbang
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Re: First time with point motors query

Postby Flashbang » Wed May 16, 2018 9:41 am

Oranoco wrote:Ah cool, thank you. May need to wire it as 2 switches as an interim measure and add the CDU when I motorise some I the other less accessible points.

Whatever switch you use they MUST be momentary contact. i.e push to make and non locking. Sprung to centre off toggle switch (On)-Off-(On) type where the bracketed (On) can't remain in that On position when the switch is released.
If power is left on the motors coil, of any solenoid point motor, it will very quickly over heat and the coil will burn out rendering the motor useless. Maximum On period should never exceed 0.5 second.

As stated above, the Hornby R044 Black point lever does not work at all well with a CDU, but all other momentary point levers or switches do work correctly!
Broken? It was working correctly when I left it.

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Oranoco
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Re: First time with point motors query

Postby Oranoco » Wed May 16, 2018 10:02 am

Thank you.

Think I might tinker with a signal box and mount switches in the roof for all the motorised points.

The Hornby switches without a CDU and single motor operation will at least get me started

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Mountain
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Re: First time with point motors query

Postby Mountain » Wed May 16, 2018 3:36 pm

Why not make a little control panel with a track work diagram on it and use the stud and probe method? Is easy enough. Use thin bolts for the electric contact for the panel side of things.

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Oranoco
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Re: First time with point motors query

Postby Oranoco » Wed May 16, 2018 10:00 pm

Long term that will probably my goal.


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