Three into two?

  • Thread starter Sarah Winfield
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JimmyB

JimmyB

Learning; but slowly!
23 Feb 2018
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#61
My phase II is not as complicated as Sahara's, I know where I will be isolating, and I will be manually changing the point (certainly in the short term), and for ease of operation I was considering SPDT/DPDT switches close to the point, the switches will need to be discreet and waterproof. Question is where is the best place to buy these, and thoughts on mounting the switches - please!
 
Gizzy

Gizzy

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#62
My phase II is not as complicated as Sahara's, I know where I will be isolating, and I will be manually changing the point (certainly in the short term), and for ease of operation I was considering SPDT/DPDT switches close to the point, the switches will need to be discreet and waterproof. Question is where is the best place to buy these, and thoughts on mounting the switches - please!
RS, Farnells or Rapid Electronics would be your best bet.

Make sure the switch is adequate for 24V dc and your max current (10 A). Get a toggle switch that can be fitted with a rubber boot, which need a circular hole (easier to drill than a square hole!)

A small waterproof enclosure to IP65 standard and a water proof gland mounted on the underside for the cable....
 
S

Sarah Winfield

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#63
Yes.

Simply feed one end of the DPDT with wires from the left hand side of the insulated joint, and from the right hand side to the other end of the switch. Then use the feed out of the centre of the switch to power your sidings.
After working all morning installing the insulated rail joiners I managed to wire the switch incorrectly!

I have taken the wires from the middle of the switch and connected them to the main controller wires; whereas these two wires need to go to my station.

It is the outer four wires of the DPDT which go to the continuous circuit rails, isn't it? I have to make certain they are the correct way round.

SW
 
Gizzy

Gizzy

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#64
I've just done a quick diagram for you Sarah....

103788_cc180495688d2a1a5a9f309f0f4534ca.png
 
Gizzy

Gizzy

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#65
Looking again at my diagram, the red wires go to the isolated track, and the blue from either the controller or a feed from your main circuit....
 
Gizzy

Gizzy

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#66
It is the outer four wires of the DPDT which go to the continuous circuit rails, isn't it? I have to make certain they are the correct way round.

SW
Yes it is, as per my diagram but marked from controller....
 
S

Sarah Winfield

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#68
Thank you Gizzy. I was just viewing the article on switches and your drawing makes it quite clear.

Others have posted lots of information but somehow it won't go into my thick head and stay there.

I've given up for the moment as I have an appointment with my counsellor later and I have to prepare for it. I'll try and get back to the opportunity tomorrow morning.

SW
 
PhilP

PhilP

G Scale, 7/8th's, Electronics
5 Jun 2013
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#69
In this instance, it doesn't matter which of the two pairs of wires is 'in' and 'out'..

It just means one way reverses the supply coming in (to the switch), and the other the supply going out. As you are only ever switching one of these it still reverses polarity across the switched contacts.
 
S

Sarah Winfield

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#70
It doesn't matter whereabouts in my station I put the red wires? And the blue wires can go anywhere on my main line circuit.

SW
I've just done a quick diagram for you Sarah....

View attachment 242339
So I don't need to use all the switch contacts? Just take two of the outside contacts and connect them to my controller/main line track?

SW
 
Greg Elmassian

Greg Elmassian

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#72
All switch contacts used. Gizzy was saying (and it backfired) red to station, blue to main

OR

blue to station, red to main

it does not matter. this is because, no matter which way you look at it, the switch can reverse the 2 leads no matter how it is hooked up...

the shorter the wires the better in terms of connecting to the main.

to the station, a central location would be better, since you are asking power to flow through the switches, and they have all kinds of contacts and jumpers underneath (failure points)

so somewhere near the "middle"

Greg