Lgb 4 Point Change Unit No 51750

Dinas Bryn

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I have checked my wireing and re-done 1 now I find they will go one way but not the other if anything the motor just chatters, I put the blades in the middle before moving the blades to one side, any ideas please Les
 
You're using dc into the switchbox? Should be ac...

Or the rack has jumped on the pinion of the point motor....take the top off, centralise the rack, and locate it over the pinion pip when uppermost.

Hope this helps....

Malcolm
 
Morning thanks Malcolm,
1 I am using ac
2 I removed the rack and put the blades in the centre
3 I then put the rack back on locating the point hole making sure I am in the tooth of the motor.
is that what you agree with?
Regards Les
 
The motor chattering sounds like it's being fed AC.
 
Sounds like you're doing the right thing...

One thing I've used to prove ( or disprove ) layout wiring, is a 9volt pp3 battery flashed to the point motor. One way round the points should switch one way, reverse the battery, and the points switch the other way.

Malcolm
 
If you've double checked the wiring, the box is indeed a 51750 not a 51800 and that the supply is AC of around 12 to 18V then suspicion must fall on one or more diodes inside the switch box.
 
Evening I have checked the box and can't find a number, inside on the left it shows 2 diagrams of points ? I seen to be unlucky with these things, bought 2 Massoth 4 unit, it worked fine until I tried to add the second unit, I will take both to the NW Meet next year Phil will sort them out for me I hope if I haven't burnt something out Les
 
Les,

The box should be orange. I don't think they have number on the point control boxes any more? If it has pictures of points and signals on the pictogram by the switches you should be alright!

I think that there are four outputs on each switch of all types of LGB EPL point control boxes?

White is Common AC for old style solonoids and also EPL Drives

Green and Yellow are for the old Solonoid type points only.

Orange is the Half wave plus or minus output for EPL drives only. Use this output and the white one for your EPLs

There are several dos and donts when using these boxes:

They can be fed through the end plugs/sockets the hold them together AND through the black and white terminals at the back (next to the four sets of terminals that switch the points). Make sure that you are feeding all the boxes you have linked up together in the same way, or that will cause a short.

Secondly the connection to the EPL drives uses the white common and the orange + or - half wave. Not sure how you are wiring your EPL drives, but if you are linking your white common returns to other points, you need to make sure you have not crossed over the black and white AC wires out there on the layout somewhere.

Thirdly as Malcolm says you need to prove that the EPL drive is working fully and the rack will travel the full distance each way when the motor is disconnected from the point. You can use a 9v battery or even a DC model railway controller on full DC to check this, provided you only apply a quick burst and then switch it off.

Another way to test is to use a pair of diodes made up into a letter Y. Each diode needs to present different ends to each other at both the double and single ends. Stick the single end in the orange terminal on the EPL drive and a neat AC feed into the other. Then use the cable bringing the other half of the AC supply to apply a burst of power to each of the two exposed ends of the diodes in turn The EPL should switch as you touch each one.

Four - Is the point working properly? Are the blades moving freely without resistance when the motor is disconnected? It needs to be on a flat surface to avoid any tensions and twists that might cause it to stick. (This can be a properly levelled ballasted road bed of course!)

If you have got this far you should be able to screw the EPL back on the point now.

Finally it doesn't always work exactly as it should, which is why LGB once produced the marvelous 52750 EPL Booster which gives the EPL drive an extra 'whack' as required and ensures things work reliably every time. Sadly these are rare beasts but once you have used one you will never want to go without!

Good luck!

James
 
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Evening James, you have given me a lot things to do so :
1 motors checked at Dave Dowling in the summer
2 it is an orange box with point dia on left side
3 I have removed the motor and cleared all ballast
4 power is taken from transformer
5 wired green and white will change to see if it makes it work
Tired now at 83 so will carry on to-morrow
Many thanks Les
 
Morning resting this morning results
1 all white and green
2 point one up rattle
down nothing
3 point two up works curve
down nothing but pushing up home
4 point three up nothing
down works straight
5 point four up works straight sometimes
down works curve sometimes

what do you all think? regards Les
 
It sounds very much to me like AC into the switch box. One or more diodes have gone. Perhaps the wiring out to the points is very long, output of transformer is low, or there a re also some high resistance joints out there??
YMMV.
 
Hello Les,

If the motors have been proved to work seperate from the box?The points without motors are free moving? Then as Philip says the switch box sounds faulty.

Not sure what you mean by white and green though? If you have connected an output wire to the green terminal the EPLS wont work. The output combination you need is orange and white for each epl drive.

James
 
I think your wiring is all cocked up mate, these boxes are usually pretty bullet proof and although you may get the occasional duff switch the other 3 will still work. Can you draw us a diagram of the wiring? The white wire is common and goes to the white dot on the solonoid, the orange wire goes to the other side and should only go to the solonoid your assigning to that switch on the box
 
Hi the furthest point is 4ft others 6inches to a foot, my friend sent me a dia showing green and white, ok I will try orange and white to-morrow on one point, if that works I will change all of them, sorry I am no good at drawing on a computer, the transformer is 1 foot away from the points many thanks Les
 
Les,

Minimans has a good point. The only isues that I have ever had with those control boxes were the odd stuck switch and a few dry or loose joints, usually where the connecting blocks are fitted the circuit board.

Here is a link to a wiring diagram showing various EPL drives wired from switch boxes. Please scroll down and view them all. If your EPL is not wired like these are, then it needs to be.....

http://www.gscalenews.com/information/signal-control

Not posted a link here before, so you may have to copy and then paste this link into your browser.

The actualy colour of the wire used doesn't matter, as long as the ORANGE output from the chosen switch goes to the orange terminal on the EPL drive and the WHITE output from the same switch goes to the white EPL terminal.

If after you have done this, it is still not working please contact me off group so that we can arrange for me to test and hopefully repair any items that you are finding faulty.

That said, please could you confirm that the EPL drives in question worked correctly when you tested them with either a pair or reversed diodes made up into a Y shape and two leads suplying AC, OR bursts of a full dc reversible supply directly into the orange and white terminals of the EPL? If you need me to send you some diodes made up into a Ys for testing purposes, please contact me off group.

We are going to crack this! EPL technology is brilliant fun to use:

Look at what you can do with it:

James
 
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Morning everyone I have been at it early and have changed all wiring to white and orange, going off your link it is LGB 51750.
The results are as follows
D works FINE
C straight sometimes with rattle, curve sometimes or nothing, if I move the blades I get a quiet hum and no movement
B works fine
A sometimes
Transformer wired right one and third one.
Les
 
Les,

Thank you and well done. Progress indeed.

To identify the issues with points C and B, try running them off of switches D and A.

If the result is no different when they run off the other switches then the issue will be at the point end.

It would also be useful to test the two points that you have already proved work well, but this time from the switches that are currently in doubt and see how they work from those.

Please could you try this and get back to us - By process of elimination we will resolve your remaining issues!

James
 
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Sorry James I should have done that will have a go to-morrow, I have wet AMD and things take along time. Many thanks Les
 
Morning all done more testing results
D ok
C ok using D wireing
B ok
A ok using B wiring, have tried again and is working better so could be the switch is tired
I was saying to my son Keith it took me 2 hours to put 4 wires into a choc box!!!!!!!!!!!!!!!!!!! he replied " how many 80 year olds do I know working on the railway Les
 
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