Interesting Point Motor problem.

[bobg]

I have 6 LGB point motors all within about 5.5 m of track (terminus). The power feed is about 2m from one end so not quite in the middle. Five of the motors will trip very happily on 12v D.C. but one refuses to work on less than 18v. It is not the one furthest from the feed, but the one furthest to the near end (if that makes sense).

I haven't got round to using the test meter on it but as the wiring is all new so I wouldn't expect to find much with that anyway, nor have I tried moving the motor to another position yet. I just wondered if anyone else had come across such a phenomena, and what caused it and what was the cure?????

:thinking::thinking::thinking:

 

[Andy Worsfold]

I'm not an expert but mine use an AC supply. 18V.

Andy

 

[bobg]

Sure Andy, but it gets rectified (to D.C.) before it reaches the point motor. Mine are wired direct, from momentary switches.

 

[korm kormsen]

sounds, like you activated your momentary switch a bit too long.
i myself did fry some turnout motors as well, before i understood the difference between DC and rectified AC.
the rectified AC is like a kind of "stuttering", intermittend DC. as such it can not fry the turnout motors.

 

[bobg]

A possibilty Korm, but not I, someone else, they were secondhand. It is possible to have burnt the windings and shorted some but not blown them. A resistance test might perhaps show that up. It would have taken a while to do that even so, not just a slightly long 'hold'.

One of the motors refused to work at all to start with, till I cleaned it out and reassembled it.

 

[Gizzy]

I used 18 V AC, rectified with 2 diodes to give half wave DC, before I took a walk down the dark side.

My motors were 60 ft from the PSU and switches, and I used CCTV 4 core twisted pair cable courtesy of Bigjack. I operate motors in pairs on crossovers.

I guess your problem Bob might be the motor itself, maybe electrical as you surmise, but it may be mechanical.

I'd be tempted to try an 18 V supply personally first in this case....

 

[bobg]

What I'm using is the D.C. (controlled) side of a 5000 series controller which gives 0 - 18V. That one motor refuses to develop sufficient power to throw the point unless the controller is turned all the way up. I have stripped and cleaned it and it is no better.

 

[Gizzy]

I originally used the 1A 50170 Transformer Controller from a set for my points?

http://www.champex-linden.de/lgb_pr...0467cf6/47d743bea2eb31b78525701b00615201.html

You can pick these up cheap enough as they are often split from sets.

For switches, I used the Gaugemaster GM511 mounted in a panel. These come with the 2 diodes to rectify the AC to half wave DC.

http://www.gaugemaster.com/item_details.asp?code=GM511&style=main&strType=g

These are far cheaper than the LGB control box....

 

[Neil Robinson]

Well, if the mechanics move smoothly enough and the supply is the same then the difference must be down to either a, the windings or b, the strength of the permanent magnet inside the plastic central rotator. One way to find out is to swap rotators between the weak and a stronger motor and observe any difference.

 

[bobg]

Well, it doesn't seem to be the windings, I've checked a couple of others as well and they all give 22-23 ohms. I suppose the next thing it to move it to a different position and see if the problem follows it, or stays where it is. i.e. prove the motor and the wiring. I can't see it being the wiring, but you have to check.

One other thing that just ocurred to me is that particular switch is a different make to the others, although it looks identical, I suppose it might have high resistance contacts, so that's another thing to check out.

Not sure how you could provide an objective test for the magnet strength, other than try to pick something up with it. :thinking:

 

[minimans]

Sounds to me like the armature is not set to the central position. check and reset the armature. then after years of experience with these using EPL 12V is simply not enough 18V min and I use a 5amp 24V supply for mine going through Std LGB switch box's. also the wire to the switches needs to be man enough for the job bell wire won't do the job reliably a good quality 14gauge wire is required not sure how they size wire in the UK anymore! and if the run is a long one then an EPL booster is a good way of overcoming any losses due to wire length

 

[beavercreek]

These are far cheaper than the LGB control box....

[/quote]

yes and no
buy 4 guage master switches, find a nice small box, make it weather proof and then have an led light to show that it is in fact powered, make a nice little neat pcb board with the diodes for each switch and also make it expandable, add the time taken and then compare to the average used price of the lgb box as about £30 or so and the difference in price is not a great saving. I know I have about six of the things!.
any one want one!

 

[Ian_S]

Morning Bob

If this is one of the point motors you bought off me - Send it back and I'll swap it out for another - Drop me a PM if needs be

Cheers

Ian S

 

[bobg]

Morning Bob

If this is one of the point motors you bought off me - Send it back and I'll swap it out for another - Drop me a PM if needs be

Cheers

Ian S

Actually I don't think so Ian, I think it was one of a previous lot, but if you've more, and I don't find a cure, I might be interested.

I like the sound of Paul's suggestion of the armature being out of sync, so I'm going to check that out later when I get time. I'll also take a voltage reading at the motor, but could do with another pair of hands for that. It's an afliction I've had since birth you know........only two hands that I cant always get far enough apart.

I actually quite like little problems like this, it makes the brain work. It just gets annoying when you don't find a cure.

Thanks for thinking of it Ian.

 

[trammayo]

I ran my only remote LGB switch on 12v DC (car battery) with a momentary switch using telecom wiring - about 4 metres - without any problems until it burnt out (some kind person said all was clear after a derailment - but it wasn't).

 

[bobg]

I had a bit of a fiddle (they can't touch you for it ) and cleaned out that point motor again, not that there was much to find. Afterwards if worked fine on 12v D.C. the only thing that might have been wrong was the pegs on the barrel may not have been mated properly, so Paul was nearest.

I now need to find a new power source as in the process I seem to have b******d the tranny it's now only giving +/- 5v. Being rather old it may be better to just to get another.