Fishmanoz Posted October 31, 2016 Share Posted October 31, 2016 Just an aside to the current frog switching discussion and to clarify on 2 points on the same port, Seeps are known to be a problem with this as their current requirement is higher than other motors, so known not to work with 2 on the one port of an 8247. Link to comment Share on other sites More sharing options...
St1ngr4y Posted October 31, 2016 Share Posted October 31, 2016 As well as tab F, did you not have wires from tabs D & E to your track (or DCC bus)? The switch in the PM1 feeds current to the frog from D or E depending on which way the point motor has been switched. If you don't have these wires connected, the wire from tab F to the frog is redundant. However, the frog will still get power, but from the point blades contacting the stock rail. I'm not an electrical expert - maybe someone else may be able to say whether loose contact from a point blade to stock rail would account for the reduced voltage.Ray Link to comment Share on other sites More sharing options...
Fishmanoz Posted October 31, 2016 Share Posted October 31, 2016 If you are droppping that much voltage across a bad connection, it will be getting hot. Link to comment Share on other sites More sharing options...
St1ngr4y Posted November 1, 2016 Share Posted November 1, 2016 @Captain90Have you resolved this problem yet?Ray Link to comment Share on other sites More sharing options...
The Captain90 Posted November 2, 2016 Author Share Posted November 2, 2016 Ray, the voltage problem has not yet been resolved. Have checked, nothing is getting hot in the point area. Link to comment Share on other sites More sharing options...
Chrissaf Posted November 2, 2016 Share Posted November 2, 2016 The switch arrangement in the Seep PM1 & PM4 point motors is very basic. It consists of springy metal contact sliding across a tinned area of PCB track. If the springy contact lacks tension or the contact area on the PCB track is worn or dirty then it is very possible for a volts drop to be introduced in the circuit (unlikely to be worn on a new point motor, but could be an issue at some point further down the line - pun intended)..As you appear to have a multi-meter. Compare the voltage measured on the frog to the voltage measured on the Seep Tag F. If F is OK but the frog is low, then check the wire terminations between the two. If F is the same as the frog, then measure the voltage to either Seep Tag D or E (depending upon which way the motor is thrown). If D or E are at the higher voltage, then the Seep sliding contact switch is introducing the voltage drop..Just to cover the point Ray made about the wiring also being needed on Seep Tags D & E. This GaugeMaster publication (link further below) will just reiterate what needs to be wired up and to where. Note: the function of the GM510 switch in the drawing is performed by the R8247 Accessory Decoder..Mind you that said, If you didn't have Seep Tags D & E wired up and you have also made the necessary modification to cut the links between the frog and the moving switch rails (I take it you HAVE cut the rail links as per the Peco recommended instructions?), then you wouldn't have got ANY voltage on the frog. The fact that you have got a voltage on the frog even if low would indicate that you have wired up Tags D & E, assuming also that you have cut the rail links as recommended when using external frog power switches..http://www.gaugemaster.com/instructions/Electro-frog%20pm1.pdf./media/tinymce_upload/b53b6410f620f7374c3d8ed86de34135.jpg.When using external frog switching. Break links at position A and solder in two new links at position B. The additional links at position B are optional but in my view highly recommended as they take away the reliance on the physical contact between the switch and stock rails for electrical continuity. Link to comment Share on other sites More sharing options...
The Captain90 Posted November 3, 2016 Author Share Posted November 3, 2016 Thanks Chris for your informative and detailed reply. I appreciate the time you and others spend in helping people on this forum.Just a dumb question. If I put one probe from my multimeter in Seep Tag F where do I put the other probe (guessing on the switch terminal) to check the voltage.Yes I have wired my point as per the above diagram. One thing I didn't do is use the Peco wire from the frog. I soldered a wire from the seep to the frog rail direct (similar to a dropper). Link to comment Share on other sites More sharing options...
Chrissaf Posted November 3, 2016 Share Posted November 3, 2016 Just a dumb question. If I put one probe from my multimeter in Seep Tag F where do I put the other probe (guessing on the switch terminal) to check the voltage..Yes you could use the switch terminal (Tag) for the other probe, either the D or E Tag depending upon which way the switch is thrown. You could also put the other probe on the dropper connection to your Bus wire. Again, which one of the two will depend upon which way the switch is thrown. If you choose the wrong dropper, you just won't get any reading..Purely a personal choice, but I used the PECO provided frog wire. I did however shorten it considerably, solder it to a normal bit of wire, and heat shrink the joint to insulate it. Link to comment Share on other sites More sharing options...
The Captain90 Posted November 5, 2016 Author Share Posted November 5, 2016 Well the saga continues. The voltage of the troublesome point has mysteriously increased to 11.7v (at last check) however is below the rest of the layouts voltage of 15.7v. Anyway I have placed the multimeter probe on the switch terminal of the PM1 and it too is showing 11.7v so perthaps I have a faulty PM1.I have three locos and if I run the Flying Scotsman & Co-Co Class 47 over the troublesome point at shunting speed all is good. However when I run the Bon Accord Peppercorn across it this causes a short. This has me puzzled.Any thoughts?? Link to comment Share on other sites More sharing options...
St1ngr4y Posted November 5, 2016 Share Posted November 5, 2016 Hi Captain,I don't think you have clarified whether you have done this - "Break links at position A and solder in two new links at position B.", as per the diagram posted by Chris. If you haven't, then you may get a short if the wheels of your loco touch the "inactive" point blade.Ray Link to comment Share on other sites More sharing options...
The Captain90 Posted November 5, 2016 Author Share Posted November 5, 2016 Yes I have "Break links at position A and solder in two new links at position B." as per Chris diagram. What is puzzling me is why its only one loco out of three that is causing a short. Link to comment Share on other sites More sharing options...
Chrissaf Posted November 5, 2016 Share Posted November 5, 2016 Are the wheels under the cab of the troublesome Bon Accord Peppercorn flangeless?.That is to say on a fixed axle and the wheels are flangeless to allow them to swing in and out over the top of the rails on corners. My Hornby A4 had flangeless wheels under the cab. I had to pack out the axle to make the wheels sit higher, further away from the rails. If you have a similar wheel situation, they maybe hanging too low as the loco goes over the points and shorting out the stock and switch rails that are of opposite polarity. Link to comment Share on other sites More sharing options...
Chrissaf Posted November 5, 2016 Share Posted November 5, 2016 Typo error correction to my last post:.I wrote "...........shorting out the stock and switch rails that are of opposite polarity."I meant "..........shorting out the frog and stock & switch rails that are of opposite polarity." Link to comment Share on other sites More sharing options...
96RAF Posted November 6, 2016 Share Posted November 6, 2016 I have a Mallard that often shorts at a particular Hornby standard point and its definitely the front bogie, but I have yet to find out exactly what is getting at what yet. Reversing through and it doesn't happen.On the other hand I have a Merchant Navy that always shorted on the same point (telling me something about the point) and when the valve gear broke and I got a replacement it was obvious where the problem was. The original gear had a metal bridge and every now and then a wheel would touch this bridge and it would pass current across to the other side and short. The new valve gear had an isolator in the bridge to prevent pass across. Link to comment Share on other sites More sharing options...
St1ngr4y Posted November 6, 2016 Share Posted November 6, 2016 I have a couple of locos whose front bogeys caused a short at points. I checked their back-to-back wheel distances with a gauge and found they were slightly narrow. Since a minute adjustment, I've had no trouble.I also concur with Chris that a flangeless wheel under the cab can cause shorts too.Ray Link to comment Share on other sites More sharing options...
The Captain90 Posted November 7, 2016 Author Share Posted November 7, 2016 Have had a most frustrating couple of hours. It is now that all three of my locos are causing a short when crossing the troublesome point. I have replaced the point motor with a PM4 (these were sent to me in error when I ordered more PM1's) and yes it is correctly aligned. When this point is activated via Railmaster the rod moves only slightly (have not yet cut it to length) but does not move the point. Also the point cannot be moved manually using the plastic piece on the point.With regards the voltage, the point voltage is now the same as the rest of the layout 15.8v however (I hope I can explain this right):When the point is set to go straight ahead (I am doing this manually by moving the bottom rod on the point motor) the voltage using a probe on the frog and and outside rail is nil but on the frog and the inside rail its 15.8v. When the point is set to go to the left the voltage is correct. It appears the switch is only working when the point is set to the left.I have installed 6 other points so far on my layout and these are working perfectly so I am at a loss at present regarding this point. Perhaps the point is the problem. Link to comment Share on other sites More sharing options...
96RAF Posted November 7, 2016 Share Posted November 7, 2016 The point should move by hand with a solenoid point motor attached or not if everything is aligned. To troubleshoot which is at fault the motor will have to come off again, then if the point moves freely and the motor moves freely it is the joning of the two that is the problem, else one or the other will probably indicate binding. Have a close look and see if anything is jamming the point mechanism like a bit of ballst or other dross, it doesnt take much. Another common failt is the point may not be laid flat, even though it look as if it is. Link to comment Share on other sites More sharing options...
The Captain90 Posted November 7, 2016 Author Share Posted November 7, 2016 Thanks RAF. Having a break from the frustration tonight and will have another look in the next day or so. Will remove motor again and check everything as you suggest. No ballast yet so this cannot be the cause. Have layed points (in fact all track) on cork so will check this as well.Still need to work out why the frog polarity is not changing. Link to comment Share on other sites More sharing options...
St1ngr4y Posted November 7, 2016 Share Posted November 7, 2016 With regards the voltage, the point voltage is now the same as the rest of the layout 15.8v however (I hope I can explain this right):When the point is set to go straight ahead (I am doing this manually by moving the bottom rod on the point motor) the voltage using a probe on the frog and and outside rail is nil but on the frog and the inside rail its 15.8v. When the point is set to go to the left the voltage is correct. I've worked out that the point is probably a left-hand point, but I can't work out what you mean by the inside rail and outside rail. Are you sure that the wires to tabs D & E are the correct way around?Ray Link to comment Share on other sites More sharing options...
The Captain90 Posted November 8, 2016 Author Share Posted November 8, 2016 Thanks Ray - you have solved my polarity problem and it is now obvious to me what I am doing wrong.As background I have a BUS around my layout with the positive being red and the negative being a black wire. I have all my points (including the problem one) wired with the positive BUS wire attached to tab D and the negative BUS wire attached to tab E. I have wired my point motors with a block connector to make future changes easier. Because of a cross member under my baseboard this particular point has had to be put in reverse to the others as there was no room for the block connector. Following Ray's post I swapped the wires over and eureka the polarities were right in line with the way the point motor was switched. No shorting by any loco.As they say you learn something new everyday and today I certainly did. Link to comment Share on other sites More sharing options...
RDS Posted November 8, 2016 Share Posted November 8, 2016 Well done Ray Link to comment Share on other sites More sharing options...
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