Tips on wiring LGB 51950 colour light signal

Retrac

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Anyone know how to wire one of these signals? Having problems even though control box is responding okay. Despite their contention that it is easy to wire I must be missing something!
 

PhilP

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An idea of how you have it wired, would help.. :wondering::)

PhilP
 

Retrac

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Thanks PhilP. Using lgb wire from signal (orange & white) to 51755 control box terminals (colour coded). Power to control box from track feed. Green led on control box indicates power is on. Feint sound from signal mechanism when control box rocker switch activated but no lights appear. Any ideas?
 

dunnyrail

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Thanks PhilP. Using lgb wire from signal (orange & white) to 51755 control box terminals (colour coded). Power to control box from track feed. Green led on control box indicates power is on. Feint sound from signal mechanism when control box rocker switch activated but no lights appear. Any ideas?
I wonder if this is a help?
image.jpg
 

idlemarvel

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You need two sets of wires, two to throw the point motor inside the black box which moves a magnet on top from side to side, and two to power the light bulbs (DC 20v ish). Either red or green will light up according to the position of the magnet which is controlling a reed switch inside the grey base of the signal mast. So it's wired in the same way that a point/switch with an illuminated point/switch lantern would be.
 

Retrac

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Thanks to Dunnyrail & idlemarvel for your responses. Very helpful. I used the spare controller from LGB starter set & got lights operational. Not sure if signal drive is faulty as I can manually change signal aspect from red to green & vice versa but not throwing electrically.
 

idlemarvel

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So it sounds like the magnet and reed switch and lights are working but the point motor bit isn't.
Do you have other point motors? Is the point motor (input terminals with orange and white dots) wired the same way as those points?
 

dunnyrail

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Thanks to Dunnyrail & idlemarvel for your responses. Very helpful. I used the spare controller from LGB starter set & got lights operational. Not sure if signal drive is faulty as I can manually change signal aspect from red to green & vice versa but not throwing electrically.
Ok have you done it via the motor being hand pushed across or just with swopping wires about? Also what are you using to power the motor? It sounds like an EPL one, but I am just guessing. A picture tells a thousand words.
 

Edgar

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Admittedly out of my league here: my understanding is Retrac states that the power is coming from the track terminals of the transformer. Should the power be taken from the accessory output?
 

Gizzy

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Admittedly out of my league here: my understanding is Retrac states that the power is coming from the track terminals of the transformer. Should the power be taken from the accessory output?
Yes it should be from the accessory output....
 

Software Tools

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Thanks to Dunnyrail & idlemarvel for your responses. Very helpful. I used the spare controller from LGB starter set & got lights operational. Not sure if signal drive is faulty as I can manually change signal aspect from red to green & vice versa but not throwing electrically.

Your drive is unlikely to be faulty, it is just not getting the right control signal.

Unfortunately, a number of otherwise reputable G scale retail web sites indicate that a 51755 control box is suitable for EPL accessories. In fact it isn't! See the following post for more.....
 
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Software Tools

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You need a need a 51750 control box for EPL "rotary motor" accessories such as the coloured light signal, and that is also probably going to be part of your issue.

The 51755 control box is for older non-EPL "solenoid coil" accessories and will not work for EPL accessories without some additional bits.

Basically, the EPL point/signal motors work by reversing the polarity of the control voltage sent to them over a two wire connection. The 51750 box has internal diodes which handle this. The 51755 box is a momentary contact type, which sends a pulse of AC through to one other the other solenoid in the accessory over a three wire connection. It is possible to fit diodes externally to a 51755 and then use a two wire connection.

The diagram (from the 51750 instructions) below shows the wiring inside a 51750 control box. It is basically a 51755 box with diodes added and an extra output terminal for the EPL accessory. You can add the diodes externally to the 51755 box to get the same result. Small, low current (1 Amp rated) silicon diodes will be fine for this.

F6DDDE22-98EB-4209-BCAC-AF07FA8E2F7E.jpeg
 

Software Tools

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I found a very old LGB diagram which shows the fitting of external diodes to an earlier version of the 51755 control box (type 5075). The connection point on a 51755 is a clamp style screw terminal rather than the round nut style on the 5075, but the principle is exactly the same.

Using 5075 with EPL device motor.jpg
 

idlemarvel

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I think the OP needs to post some pictures and a wiring diagram please as we are guessing around the problem at the moment.