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Discussion Starter · #1 ·
got a new loco through the pos yesterday and went to try it and it didn't work, eventually put one of my locos on the track, and that didn't work!

farted around a bit, changed a set of points and everything worked........BUT.........

i can't see how these points could possibly be giving a short circuit, as i'll explain.

feed is at toe of points (LH curved elecrofrog peco 55). the two spurs of the points lead to sidings only. There are no other electrical feeds anywhere, as this is test track only, and it worked about a week ago no matter which way the point was turned, BTW the loco is between the feed and the point, so not isolated by the point.

i must have a shirt circuit at the point when its switched one way only - any ideas best way to check this?

thx
 

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Hello.
First up check the connections to the track. How do you know you have a short circuit ? Is your controller lights flashing in some way ? Is your controller working properly or at all ? You don't say whether you are using DC or DCC. You need to give us a little more information but first of all check all connections.

QUOTE (cunnini @ 21 May 2008, 09:32) <{POST_SNAPBACK}>got a new loco through the pos yesterday and went to try it and it didn't work, eventually put one of my locos on the track, and that didn't work!

farted around a bit, changed a set of points and everything worked........BUT.........

i can't see how these points could possibly be giving a short circuit, as i'll explain.

feed is at toe of points (LH curved elecrofrog peco 55). the two spurs of the points lead to sidings only. There are no other electrical feeds anywhere, as this is test track only, and it worked about a week ago no matter which way the point was turned, BTW the loco is between the feed and the point, so not isolated by the point.

i must have a shirt circuit at the point when its switched one way only - any ideas best way to check this?

thx
 

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Discussion Starter · #3 ·
QUOTE (TonyDaly @ 21 May 2008, 09:46) <{POST_SNAPBACK}>Hello.
First up check the connections to the track. How do you know you have a short circuit ? Is your controller lights flashing in some way ? Is your controller working properly or at all ? You don't say whether you are using DC or DCC. You need to give us a little more information but first of all check all connections.
 

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Discussion Starter · #4 ·
hi, should have said that when i change the point it works, so connectivity to the point must be fine.

its DC, not DCC, and is a terminus type straight track one point system. changng the point causes the issue.

thx
 

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Hello.
Changing the point shouldn't make any differance if the loco & the track feed are at the toe end of the point. It looks like the point is the cause of your problem. First of all "What kind of point is it ?" Is it electrofrog or insulated frog ? Are you getting a short or does it simply not work ?
Check the point for any stray wire or connection. You must be getting a short because as I said above "The position of the point should make no differance because your Track feed & Loco are both at the toe end of the point.

QUOTE (cunnini @ 21 May 2008, 10:08) <{POST_SNAPBACK}>hi, should have said that when i change the point it works, so connectivity to the point must be fine.

its DC, not DCC, and is a terminus type straight track one point system. changng the point causes the issue.

thx
 

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Hi
When you say you "Change the point" I assume you mean normal to reverse position rather than physically changing the point itself?
As you're using live frog points are you using frog switching?
If not, I suspect the points moving switch blade isn't making good contact onto the fixed stock rail. Hence no power in one direction but its ok in the other. If this is the case, carefully clean the inside faces of both the switch and stock rails where they meet. Use a fibre brush or if not available, then the tip of a scalpel type knife and carefully scrape along the two faces.
Long term fit frog switching.

If frog switching is used, then use a multimeter set on dc volts or a 12volt lamp with fly leads to check conections are good. Remove all locos then turn up the track power. Place the two meters leads or the lamps leads at the tip of the point on both rails. You should get a full 12 v or more reading or the lamp illuminates. Keeping one lead at this position then slowly move the other rails lead up through the point and out past the frog and beyond the next fishplate (rail joiner). If you lose the reading or the lamp goes out anywhere it is here or just back towards the feed end of the point you need to investigate further. If you don't lose the reading then return to start and do the same on the other rail, if necessary going out past the fishplate at the ends of the point to see if any loss of power is found.

Good luck
 

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Hi Brian.
His Loco & Track feed are both at the toe end of the point so the position of the point blades should have no bearing on whether the loco runs or not, Except if the point is causing a short in some way when he changes the position of the point blades.

QUOTE (Brian @ 21 May 2008, 10:59) <{POST_SNAPBACK}>Hi
When you say you "Change the point" I assume you mean normal to reverse position rather than physically changing the point itself?
As you're using live frog points are you using frog switching?
If not, I suspect the points moving switch blade isn't making good contact onto the fixed stock rail. Hence no power in one direction but its ok in the other. If this is the case, carefully clean the inside faces of both the switch and stock rails where they meet. Use a fibre brush or if not available, then the tip of a scalpel type knife and carefully scrape along the two faces.
Long term fit frog switching.

If frog switching is used, then use a multimeter set on dc volts or a 12volt lamp with fly leads and remove all locos then turn up the track power. Place the two meters leads or the lamps leads at the tip of the point on both rails. You should get a full 12 v or more reading or the lamp illuminates. Keeping one lead at this position then slowly move the other rails lead up through the point and out past the frog and beyond the next fishplate (rail joiner). If you loose the reading or the lamp goes out anywhere it is here or just back towards the feed end of the point you need to investigate further. If you don't loose the reading then return to start and do the same on the other rail, going out past the fishplate at the ends of the point.

Good luck
 

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Fault finding is a logic process.....Eliminate everything til you find the answer.

Try another model.

Works - Take model back to shop or repair.
Not work - Check the connections.

Works - Replace or secure wires.
Not work - Check the track for stray wires or metal.

Wires or metal around - Remove and try again.
None - Replace points for normal track to test for electrical flow.

Works - Track faulty
Not work - erm............
 

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Discussion Starter · #9 ·
i pretty much know the fault lies with the point - see my O level physics was useful!! i just need to know waht to look for in the point for faults and how to find the fault.

i'm particularly confused as this wasn't a problem a week ago, and has recently occurre, but without any changes to the trackwork/wiring etc.

thx for all the help so far, but please add further things to check etc !!
 

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QUOTE (cunnini @ 21 May 2008, 19:20) <{POST_SNAPBACK}>i pretty much know the fault lies with the point - see my O level physics was useful!! i just need to know waht to look for in the point for faults and how to find the fault.

i'm particularly confused as this wasn't a problem a week ago, and has recently occurre, but without any changes to the trackwork/wiring etc.

thx for all the help so far, but please add further things to check etc !!

Hi

OK... heres a few things to think about and check...

If it was working one day and not the next its not wiring unless its related to changes or failure of a component in the point...
such as an spst changeover switch on the frog etc.

Its going to be either a point problem or something silly and small thats just not noticed... if it was OK one day and not the next, its probably the "silly thing".

So... keep first checks simple... its often staring you in the face.

Example: when I was wiring my layout I was also progressively replacing the last couple of sleepers on each board with copperclad. I came into the layout room one day to continue and connected my screamer across the rails and it sprung into life. (The screamer is a piezo buzzer type device I connect across both rails when wiring to warn me I've screwed up and swapped left bus wire to right rail dropper accidentally - I use it as lamps and meters are useless when U are under the board with a soldering iron)

It took me hours and hours to find the problem - and I was really P-ed off when I found it.

I'd a box of copperclad sleepers on the layout and when I cleaned up the night before I'd chucked the spares at the box and one had missed the box and landed face down on the track - so small it wasn't noticed and copper side down so it looked harmless but wasn't... A B**** frustrating problem to say the least on a complex board which had a dozen hand made points including 3 slips and two diamonds on it - which I of course blamed first so I de-wired de-wired the lot!..... making a lot of work when simply clearing stuff off the board would have found and fixed it!

So - first do the obvious:

* make sure no wire other than the two feeds at the toe are connected.
* Take everything off the track and vacuum it all over. if possible separate the toe end lead in track from the layout for the tests so U are just working with a Y shaped bit of track.
* disconnect the controller from the track too (you want nothing else electrical or electronic connected when using a meter to check for shorts)
* check with a meter to reconfirm everything.
* If its still a problem, Look at the gaps between closure rail and frog - has either of them closed up?
* have either of the two gaps at the heel end/frog rails closed up?
* are you switching frog polarity? if so disconnect the switch centre or common wire - does this fix it?

check between the point blades and the closure rail - has a tiny bit of metal, small screw or wire end dropped in there? run a fine screwdriver tip between closure rail and point blade to dislodge the "metal or invisible stand of copper" and then Vaccum the point really carefully just in case.

recheck

if the short is still there and you can't see the problem then separate the point from all other track and repeat the test.

For perfect reality with Peco - use other brands (only joking, sort of...)

DO consider making some mods to the point though.

* totally isolate the frog. from every other rail. for OO modellers the code 75 its almost already done for you - haven't looked at an N scale peco point for years so don't know if it is or not now - if not, get out the dremel..... and cut it.
* solder wire from closure rails to adjacent stock rails (LH closure to LH stock rail) (RH closure to RH stock rail)
* remove those silly tabs if they are there (are they there in N?) - if you do the first two things they aren't needed anyway. They are bl**dy useless things as the layout ages, they always fail one way or another
* solder a fine wire between closure rail and point blade (this linkage fails after ballasting often as the eyelet corrodes and they
become elctrically iffy and sloppy too.
* connect the frog to a changeover device that will change the frog polarity as the point is changed. I prefer to do it with my
own MASTERswitch product but the peco switch will work too.

Richard
 

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QUOTE (cunnini @ 21 May 2008, 11:20) <{POST_SNAPBACK}>i pretty much know the fault lies with the point - see my O level physics was useful!! i just need to know waht to look for in the point for faults and how to find the fault.

i'm particularly confused as this wasn't a problem a week ago, and has recently occurre, but without any changes to the trackwork/wiring etc.

thx for all the help so far, but please add further things to check etc !!

I think we need more information please.
Do you have a loco stabled or a metal buffer stop in any of the two sidings leading off from the point? If so remove it/all and retest, as I wonder as your using live frog points and probably no Insulated joiners after the frog, if track power is passing through a stabled loco (or metal buffer stop) and causing a short when that route is selected???
Does the loco run ok everywhere else?
Are any other locos causing the same problem at the same location?
Does the loco run through the point ok when it is set for the straight (or the diverging) route? Not sure which direction is causing the problem or is it both ways??
Does the controller give any indication of a short circuit? - a red light comes on, buzzes , other locos stop which are on the same controller etc
Or is it more a loss of track power in that area i.e. open circuit?
Use a multimeter to test connections if a short circuit is the problem as Richard has suggests.
If not a short circuit problem, then use the meter on dc volts (Or a 12v lamp) and with power on and check for open circuits - loss of reading or the lamp goes out.
 
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