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Old 19-02-2018, 12:25 PM   #1
peterbalcombe
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Default Conflicts driving me nuts

My OO DCC layout is equipped with Cobalt digital motors (mainly the previous generation) but including two of the latest IP ones. It is powered by a NCE powercab and takes the form of an L shape fiddle yard to terminus. Between the station throat and the fiddle yard the track is single line. The turnouts - peco code 75 large radius electrofrog (8 in total) all work perfectly with no conflicts and are readily traversed by all my steam outline locos. My peco electrofrog double slip however is a total pain in the butt. It is readily traversed by tender locos which have tender pick ups with the frogs disconnected with no sign of hesitation and no problems at other turnouts. Connecting the frogs to enable passage of tank locos immediately throws up conflict problems for both tender and tank locos leading to loud noises from the Powercab connector and some point motors to other turnouts activating which are only resolved by removing the loco from the crossover or disconnecting the frogs. I have tried rotating the cobalts on the double slip through 180 degrees to no benefit. I have tried changing connections to the cobalts from the powerbus over - again without benefit. Connecting a Hex frog juicer adds to the noise but does not solve the problem although previously for many months did help (perhaps I have blown it somehow). Before I go through the major task of ripping out the double slip altogether and replacing it with two simple points ( less than easy because of baseboard joints and the fact that all track is ballasted has anyone any ideas please?
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Old 19-02-2018, 12:39 PM   #2
Flashbang
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Hi
I assume the Electrofrog DS has Insulated Rail Joiners (IRJs) fitted on all four rail ends - On the Vee rail ends.

The outer curved stock rails don't need IRJs on DCC as the polarity each side of the DS is always the same where DCC is concerned. But if they are fitted making eight IRJs in all it doesn't matter.

I would commence by carrying out the following tests in a logical order.....

Ensure any rail feeds (Droppers) attached to the DS outer stock rails are to the correct polarity bus wires and they match all the rails leading into and out of the DS after the IRJs.
Ensure left hand end motor switches the right hand ends frog and same for the other right hand motor that it switches the left hand end frog.

Its worth seeing if you can determine if one (or both) motors frog switches change over the frog polarity before the actual points switch rails have moved over sufficiently and broken their contact to the moving away from stock rail. This would result in a motors switching being 180 degrees out of phase to the point and causing a short! Adjustment to the Cobalt's fulcrum plate should resolve.

Next, I would disconnect the two frog feed wires from each Cobalt allow them to lay in free air but ensure they can't touch anything.

Test the DS in all positions for other possibilities...
Is there a short on the DCC system? Yes, most likely is you have a crossed pair of droppers on the stock rails. No, then reconnect one frog wire to its motor and retest. Is there now a short in any position? Yes reverse the two DCC input wires to that frog feed on the Cobalt and retest. No, move to other frog wire and reconnect it. Has the short reappeared? Yes, reverse this motors two DCC frog feed wires. No, then the problem has been resolved by one of the other actions previously.
Enjoy a well earned cuppa while running trains!
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Old 20-02-2018, 05:35 PM   #3
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Thank you Flashbang - now resolved - and am feeling foolish. Guess which idiot had connected the frogs to the the wrong point motors!
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Old 20-02-2018, 05:37 PM   #4
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Easily done Peter
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Old 21-02-2018, 12:29 AM   #5
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You're not the first & you won't be the last.
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