Any Mains Operated Equipment That Used in Public Should Be Tested Regularly
MALDON TRACK
All wiring should be completed by a competent and skilled person, and checked by a qualified Electrician.
Any mains operated equipment that used in public should be tested regularly.
To wire an MT point so that two rail or three rail locomotive may be used.
Two rail track layout – both rails have a different polarity
Three rail track layout – the outer rails are the same polarity, the middle rail is the opposite polarity.
The MTstandard three rail version of the 38 inch point.
The leaver (on the standard points) switches the path of the current on the centre rail from the through centre rail to the branch centre rail. The frog is the same polarity as the outer rails.
With the two rail version of the 38 inch point, the frog is isolated; the branch line away from the frog would normally be isolated from the layout by an isolated fish plate (isolated rail joiner). The loco power pick up is usually on the front pair of large wheels and repeated on the back pair of large wheels, so that the frog is easily bridged by the locomotives power pick ups.
Some trains only pick up on one set of wheels so that the frog can not be bridged; in this case a second switch needs to be fitted to power the frog. This is shown in part two.
Items required
3 - CoreCable or single strand cable
There is very little power involved with this project about 5 Amp at 24 volts, seek advice if in doubt.
The means and tools will be required to strip the end of the cable and prepare the cable for use.
10A toggle switch DPDT F
Maplin Code JK30H
Crimp connector set or solder iron
To connect the cable to the switch
ABS Box MB1
Maplin Code LH20
The means and tools will be required to drill 2 – 6mm holes in the sides of the base of the box for cables in and out, and the means to cut a 12 mm hole in the top of box to hold the above switch. Holes to fasten the box to the layout may be necessary.
5 amp Terminal block
Maplin code L97AR
An electric test meter or a 12 volt car bulb with wire leads fitted would assist the person wiring up a circuit, to test their work.
1 length of wire about 30 mm (1 1/4 inches) long to bridge switch.
Method
Assemble the switch on to the lid of the ABS box, and wire the out let side of the terminal block as in the diagram below, and place the terminal block into position inside the ABS box.
On the centre terminals of the switch, bridge the connection so that both the centre terminals are connected.
On the MRCstandard three rail version of the 38 inch point, the frog is connected to the outer rails by a thin wire running in a slot that has been machined on the underside of the point base. This connection need to be broken so that the frog is not connected to any of the outer rails, and new connections made. One wire to each of the outer rails (labelled 1 and 3) and one to the frog (labelled 2).
Introduce three wires from the pointto the 5 amp terminal block.
Outer rails (labelled 1 and 3) and one to the frog (labelled 2).
Connect the wire which came from the frog (labelled 2) to the centre of the pole switch.
Connect the wire which came from outer rail (labelled 1) to one of the switch terminals and the other wire to the terminal next to that.
When the switch is in the middle position the frog is isolated from both outer rails and each of the outer rails are isolated from each other.
When the switch is thrown the frog and outer rails are connected.
By introducing a wire from the centre rail a LED or small bulb could be powered to show that the point is in two or three rail mode.
Test circuit.
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Duel points