Longhaireddavid Posted July 19, 2015 Share Posted July 19, 2015 I have been tearing my hair out this weekend trying to get these PMs to work. I have no trouble with them moving the points. I made a paper template and used the double sided mounts and each motor is fixed firmly to the foamcore board that I am using for the base. However, I am completely mystified and could do with a second opinion. Firstly, the Peco Code 83 electrofrog points have come straight off my old HO layout where the frogs were driven by Hex Juicers and I had no trouble at all. However, I am getting continual shorts when trying to run a loco over any of the points. Firstly, I checked that I had all of the point jumpers in place - I have wired each point rail to its accompanying stock rail. I have then run the frog wire to the third connector on the Cobalt - clearly marked Frog. Whenever a loco hits the frogs I get a short and the whole system resets. Next I got a set of red and green LEDs with a suitable resistor and wired the tails of each up to the track. I then connected them to the resistor and then on to the third connector on the Cobalt marked Frog. I was expecting to see either the green or the red LED come on depending on the point setting. What I am getting is just the red. When the point switches,the red goes out but the green doesn’t come on. I have also checked the operation with the frog wire disconnected so only the LED connection is fitted to the third connector. Lastly, I have connected the LED array to an insulfrog (I have a mix of types) and I still only get the red LED coming on. I am sure that I am doing something stupid or I have misunderstood how these things work but this has kept me going all weekend. Link to post Share on other sites More sharing options...
terrysoham Posted July 19, 2015 Share Posted July 19, 2015 I suspect that you have introduced a short somwhere. Do you have a multimeter? Using one of these properly will tell you a lot more than wiring in leds. If you haven't got one either borrow or buy one. If you have one already then I can try to help you further. Let me know. Are you using hex juicers on the new configuration? Does it happen with all your points or just one? Finally, stop worrying and tearing your hair out as this problem will have a solution. If you haven't got a multimeter to hand then I suggest that you walk away from the problem and leave it alone until you have one. Kind regards Link to post Share on other sites More sharing options...
Longhaireddavid Posted July 19, 2015 Author Share Posted July 19, 2015 I have a multi meter and have been using it furiously - grin. I will try and draw up what I get when I use it. There are no overall shorts on the board. The loco will run everywhere except on the frogs of the electrofrog points. needless to say, it runs perfectly over the couple of insulfrog points. I will be back with a drawing Link to post Share on other sites More sharing options...
Longhaireddavid Posted July 19, 2015 Author Share Posted July 19, 2015 OK, I have run a multimeter over one of the points. The following shows the results (if you can follow what I am saying). This is without power applied to the system, so the track is electrically dead. Link to post Share on other sites More sharing options...
smokebox Posted July 19, 2015 Share Posted July 19, 2015 I have been tearing my hair out this weekend trying to get these PMs to work. I have no trouble with them moving the points. I made a paper template and used the double sided mounts and each motor is fixed firmly to the foamcore board that I am using for the base. However, I am completely mystified and could do with a second opinion. Firstly, I checked that I had all of the point jumpers in place I think you should remove the links which are in line with the rails, those which are about half way between the hinge of the moving rails and the frog. These links are fitted as standard on modern Peco points to bridge the gap in the rails. Older points don't have the rail gaps or the links.Not sure if this is the cause of your problem, you may have already removed them. Link to post Share on other sites More sharing options...
Brian Posted July 19, 2015 Share Posted July 19, 2015 Hi The Cobalt ip has an internal electronic change-over switch which feeds the Frog terminal 3 from the DCC arriving on terminals 1 & 2. If the DCC on these Terminals 1 & 2 is the wrong way around you'll get a short. Try swapping the wires on 1 &.2 around and retest. If that doesn't solve the issue remove the frog feed wire on terminal 3 and see if the short has then gone. If it has it's something in the Cobalt or the wiring to it that's not correct. If it's still present then it's likely there is a problem with the point or its wiring. Also if you have bonded each stock rail to its adjacent closure rail, double check the the two under rail bonding links fitted by Peco are removed and there is no linking wire left present that could connect across the gap. Link to post Share on other sites More sharing options...
Longhaireddavid Posted July 19, 2015 Author Share Posted July 19, 2015 Here is what the underside of one of the electrofrogs looks like. As I said, this worked fine using a Hex Juicer (Tam Valley). I haven't had to cut anything before. Link to post Share on other sites More sharing options...
gwrman Posted July 19, 2015 Share Posted July 19, 2015 I think you've got the wrong terminals for the switch try looking here http://www.dccconcepts.com/vamr/owners-manual-cobalt-ip-digital-point-motors Nigel Link to post Share on other sites More sharing options...
smokebox Posted July 19, 2015 Share Posted July 19, 2015 Link to post Share on other sites More sharing options...
Froxfield2012 Posted July 19, 2015 Share Posted July 19, 2015 Here is what the underside of one of the electrofrogs looks like. As I said, this worked fine using a Hex Juicer (Tam Valley). I haven't had to cut anything before. I think Brian is referring to the two links usually found where I have tried to add red circles. I hope I'm right, but if present they should be cut/removed. However, Brian points out the one thing that has given me problems with using cobalts to switch polarity on frogs: make sure the power wires are the right way round! And if using cross overs with the point motors opposite ways round take especial care! I have often proved myself a complete idiot over these basics. However, I find Coblats work well when correctly wired up. Brian, I hope I haven't done you a dis-service here. I have always found your website a fount of valuable knowledge for which much thanks. Richard Link to post Share on other sites More sharing options...
Longhaireddavid Posted July 19, 2015 Author Share Posted July 19, 2015 I think you've got the wrong terminals for the switch try looking here http://www.dccconcepts.com/vamr/owners-manual-cobalt-ip-digital-point-motors Nigel AFAIK the manual says that I should use 1 & 2 for bus power and 3 for the frog control. That is what I am doing. Certainly, the LEDs respond to the change in the frog polarity. The problem is that one goes red but the other doesn't light up green. post-19059-0-13742600-1437330954.jpg I think Brian is referring to the two links usually found where I have tried to add red circles. I hope I'm right, but if present they should be cut/removed. However, Brian points out the one thing that has given me problems with using cobalts to switch polarity on frogs: make sure the power wires are the right way round! And if using cross overs with the point motors opposite ways round take especial care! I have often proved myself a complete idiot over these basics. However, I find Coblats work well when correctly wired up. Brian, I hope I haven't done you a dis-service here. I have always found your website a fount of valuable knowledge for which much thanks. Richard There are no links at these points. I reiterate that these points were working perfectly when controlled by outputs from a Tam Valley Hex Juicer. I have checked on the polarity of the four Cobalts that I have fitted. I used orange in socket 1 and blue wires in socket 2 for this and all of the orange are connected to one bus and all of the blue to the other. Link to post Share on other sites More sharing options...
Longhaireddavid Posted July 19, 2015 Author Share Posted July 19, 2015 AFAIK the manual says that I should use 1 & 2 for bus power and 3 for the frog control. That is what I am doing. Certainly, the LEDs respond to the change in the frog polarity. The problem is that one goes red but the other doesn't light up green. There are no links at these points. I reiterate that these points were working perfectly when controlled by outputs from a Tam Valley Hex Juicer. I have checked on the polarity of the four Cobalts that I have fitted. I used orange in socket 1 and blue wires in socket 2 for this and all of the orange are connected to one bus and all of the blue to the other. I have just reversed the wires into one of the electrofrogs (swapped 1 and 2) and I still only get the red led lighting. Nothing from the green when the point is in that direction. Perhaps I should go back to hair tearing - grin. Link to post Share on other sites More sharing options...
RMweb Gold Mick Bonwick Posted July 19, 2015 RMweb Gold Share Posted July 19, 2015 The common crossing (frog) should be completely isolated from all other rails if it is not connected to any power source. Try removing the connection to the frog from the other end (cobal, juicer or whatever) and use your multimeter for the same tests. If any of them show a circuit exists, then the frog is not isolated and you will need to seek out where the join is that connects it to another rail. Refer to your diagram on post #4 if I'm not making myself clear (which has been known to happen :-) ) Link to post Share on other sites More sharing options...
phoenix160 Posted July 19, 2015 Share Posted July 19, 2015 I think you should use the switch in position 4 5 and 6 the common being position 6. Position 3 is a low power switch which works with position 1 and 2. Position 4 5 and 6 gives you a switch which is left , right and common up to 5 amp Link to post Share on other sites More sharing options...
terrysoham Posted July 20, 2015 Share Posted July 20, 2015 The common crossing (frog) should be completely isolated from all other rails if it is not connected to any power source. Try removing the connection to the frog from the other end (cobal, juicer or whatever) and use your multimeter for the same tests. If any of them show a circuit exists, then the frog is not isolated and you will need to seek out where the join is that connects it to another rail. Refer to your diagram on post #4 if I'm not making myself clear (which has been known to happen :-) )I agree.Have you done this yet? What are the results? Kind regards Link to post Share on other sites More sharing options...
Longhaireddavid Posted July 20, 2015 Author Share Posted July 20, 2015 Today, I built a test rig with just one point and motor. I had a bit of trouble but it seems that the Cobalt cares about which way the DCC bus is connected. The shorts were happening because, with the bus connected one way, the frog was being given the opposite polarity, if you see what I mean. I still don’t have the LEDs working but I can get to that later. It seems that I have cracked the problem. Link to post Share on other sites More sharing options...
smokebox Posted July 20, 2015 Share Posted July 20, 2015 Do a wiring diagram or picture of how you have connected the LEDs. Link to post Share on other sites More sharing options...
Brian Posted July 20, 2015 Share Posted July 20, 2015 <Snip>I had a bit of trouble but it seems that the Cobalt cares about which way the DCC bus is connected. The shorts were happening because, with the bus connected one way, the frog was being given the opposite polarity, if you see what I mean. This is exactly what I was referring to in post 6 re if you're getting shorts try swiping around wires on 1 & 2. :-) To note: I found the other day one of my Peco electrofrog points, which all have had the two little link wires removed from the underside of the two gaps in the closure rails, that one closure rail had managed to creap forwards and closed up the gap. Result was a short! Easy to rectify by inserting a thin blade in where the gap should be to force the rails apart and re open the gap. I would look at temporarily removing any LEDs until you have the motor and point working correctly. As far as I'm aware all Peco new electrofrog points come with the two closure rail gaps linked out by a fine wire across each gap. What happens if you temporarily remove the frog feed wire from terminal 3??? Link to post Share on other sites More sharing options...
Longhaireddavid Posted July 21, 2015 Author Share Posted July 21, 2015 It seemed that changing the polarity worked. I did drop the LEDs for now. I found that I still had a couple of Insulfrogs so I purchased a couple of Code 83 #5s from Hattons yesterday and they arrived at 11am this morning- how good is that. I spent the rest of the day removing the odd ones and putting the new ones in. Until I wired up the points everything seemed OK. Now I have a layout with all of the points and point motors in place but a short that I can't find! I am going to decouple all of the motors completely and get the rest electrically sorted. Then, one by one, I will feed in the 7 points. Once that is done, I will build my little offsite staging. Only then will I attempt to put the LED routing board in. In case you wonder what I am doing, I am building a late 1960s US HO switching railroad set on a route between Hartford, Connecticut and Boston, Mass and placed at a fictitious town called Sunset (The Sunset & North Eastern Railroad). The yard I am building is an industrial complex some 2 miles from the main home of the railroad. It will be serviced by an SW1500 (Broadway Limited DCC+ Sound) and a Boston & Maine RS-3 (Bachmann DCC and Sound) with very occasional passenger visits from a New Haven Budd RDC Walthers + Digitrax DCC and Sound). All in 8' x 1' 4" Link to post Share on other sites More sharing options...
Longhaireddavid Posted July 23, 2015 Author Share Posted July 23, 2015 I have sorted the problem. The solution was quite simple if not intuitive to me to solve. I had a simple philosophy. I was using blue and orange wires for the point motor DCC connection (to keep them different to the red and black of the main track feed onto the bus). I ensured that all the motors had the same polarity - blue to socket 1 and orange to socket 2. Wrong!. It appears that the Cobalt works differently from the Hex juicer. The Juicer seems to make a random selection of polarity at switch on and adjust it when the need arises. It seems the the Cobalt (because it has to feed the LEDs which cannot be random at start up but must reflect the actual state) feeds the frog in accordance with the polarity of the incoming DCC connection. Then, when the point is switched, it switches the polarity of the frog. At least this seems to be how it looks when checking continuity. It is years since I studied electronics so excuse the "Peter and Jane" approach which may not be factually correct but is right in practice. This means that, if I wire a facing point up the same way as a trailing point then one or other will short. This can be seen with a meter where the frog has a short to the wrong point blade. By swapping the feed wires to the trailing points everything started to work. I can see nothing in the documentation that would have warned me of this. However, it is sorted now and everything is working exactly as it should. I have also made progress on the red only LED result. It turns out that I was using a resistor which was fine for the Red LED but too small for the Green and so the green was burning out. I have now put a 1k resistor in the chain and both LEDs work. Link to post Share on other sites More sharing options...
Talltim Posted July 23, 2015 Share Posted July 23, 2015 Strange. You'd think it wouldn't matter which way round an AC powered device was wired. So the frog was switching, but was always the wrong polarity? I suppose it's something to look out for when mounting the point motor too, if you mount it under the toe of the point it will be the other way round to if it is under the body of the point Link to post Share on other sites More sharing options...
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