Joined: 19/06/2004(UTC) Posts: 1,412 Location: Home
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My BR78 (H0) short circuits at al my non electric rail crossings.
Then the Intellibox runs into short circuit mode (safe) and shuts down the power. Then i need to replace the BR78.
It happened mostly when running on slow speeds (<70%).
I personally think that the wheel flens or cog-wheels hits the 3rd rail and creates this short circuit.
But i'm not certain.
Does anyone have the same problem and knows what causes this problem? And how to solve this problem.
Thanx anyway!
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Märklin | HO | C+K Track | Digital | I+II+III+IV+V | Power and control by Uhlenbrock | Win-Digipet |
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Joined: 25/11/2002(UTC) Posts: 66 Location: ,
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Hi, welcome to the forum, That's some rather uncommon behaviour you are discribing, a Märklin loco shouldn't have any problems on Märklin track.
First try to look at some basic things like: do the problems owith other loco's ?, does the driving direction make difference, is it the same when you enter the crossing in reverse ? does it make any difference when driving onto the crossing from another side?, aren't the center contact studs bent? You haven't mentioned which crossing you use, c-rail has three different type: 24740, 24640 and 24649 with each of them having different angeles.
regards, Winston
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Joined: 19/06/2004(UTC) Posts: 1,412 Location: Home
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I use the M24640 crossing and also the M24649.
But the problem with the M24649 is less then with the M24640.
The problem occur in all the directions.
The BR78 is the only loc. that have this problem. The other 5 locs run just fine over the crossings. Also at very slow speeds.
My locs (E44, E103, V200, V360, BR78, BR85 and also the E194(which is in repair)). |
Märklin | HO | C+K Track | Digital | I+II+III+IV+V | Power and control by Uhlenbrock | Win-Digipet |
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Joined: 25/11/2002(UTC) Posts: 66 Location: ,
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Hi Timaximus,
Because you only have trouble with one loco it's obviously there's something wrong with the loco.
I've examined my 24640 crossing a little closer today and noticed that on a certain point the space between the wheel and the center stud is very little.
A possible cause for short circuits could be that one or more wheels of your BR 78's axles are positioned wrong on the axle, just a small deviation could make the wheel touch a stud.
You could check if all wheels are positioned correctly by measuring the distance between the flanges, it should be exactly 14 mm.
Good luck, Winston
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Joined: 19/06/2004(UTC) Posts: 1,412 Location: Home
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The problem has been detected: the Cogwheels are the problem.
After checking al the other possible causes. I did the following:
Before the discovery i first isolate the stud around. That means i put some isolation around it but leave the top clear so the contact sled can keep connected with the power rail. After this isolation step the problem still occur.
So the second thing a did is isolating the tops of the studs. And voila the problem is solved. For the isolation i use some painters-tape. And exactly at the location of the stud at the side of the loc where the cog-wheels are i see a clear black spot of oil from the cog-wheels.
But the next question is: did Marklin made a mistake whith the design of this loc at this particular point. Or is this just one of a million problem that only i have #;) |
Märklin | HO | C+K Track | Digital | I+II+III+IV+V | Power and control by Uhlenbrock | Win-Digipet |
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Joined: 25/11/2002(UTC) Posts: 66 Location: ,
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Hi, I'm glad you've localized the problem, solving it now is another point, maybe you can try to lower the stud by shaving it off just a little, half a millimeter might be sufficient.
It could be that Märklin made a mistake when designing the crossing, when the BR 78 was first made, c-track didn't even excisted. I've looked at several of my loco's but all of them have just enough clearance of the studs, but I have no br 78 in my collection to check.
Isn't there anybody else on the forum with a BR78 and this particular crossing ?
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Joined: 19/06/2004(UTC) Posts: 1,412 Location: Home
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Hello,
I will isolated the studs around (also the topsection). That works just fine. And when i get trouble with real damage of the isolation rubber in a short time, because of train passages, i still can cut-off the top of the studs.
Thanx. |
Märklin | HO | C+K Track | Digital | I+II+III+IV+V | Power and control by Uhlenbrock | Win-Digipet |
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