DCC frog juicers not switching - short circuit?

[Corbs]

Hi folks,

Spent a good deal of yesterday trying to trace a fault on the layout. It's been running ok until now so this is very puzzling.

Setup is:

NCE 5 amp booster

3 districts with circuit breakers

NCE powercabs and wifitrax for control

 

On one of the districts (only one), there are 4 electrofrog points with frog juicers, and a return loop polarity switcher.

The problem is that when a loco runs across 3 of the 4 points OR the return loop switching track, the district shorts out.

Normally I would expect the frog juicer to kick in and switch the polarity on the frog/return section, but it seems that it's not firing.

The weird thing is, that if I wiggle the dropper wires to one of the track feeds, it shorts out too.

Previously we had a power problem where there weren't enough amps to get the frog juicers to work, but this has the 5 amp booster and doesn't explain the wire wiggling issue.

 

On the trouble section, I even tried rewiring it all to try and get rid of any loose ends or defunct wires.

 

Any ideas? We would be grateful for any help as it's infuriating.

 

[F-UnitMad]

3 hours ago, Corbs said:

The weird thing is, that if I wiggle the dropper wires to one of the track feeds, it shorts out too.

Wiggling a wire causes a short - that rings alarm bells to me!!

Frog juicers can fail, of course, albeit rarely, like any component. I've had a Tam Valley momo juicer fail myself.

Is it possible to observe the LEDs (I'm assuming your juicers have them?) as a piece of rolling stock is pushed slowly through the formation, checking both routes through each point one at a time, to see if they swap correctly? It doen't have to be a loco - metal wheels on anything will operate a frog juicer.

 

As an aside, I'm surprised the Anti-Frog Juicer Brigade haven't arrived yet, to point out the error of your ways..... 🙄😁😉

[Corbs]

It’s so strange, we checked the wiring in case one of the droppers was wired back to front but nope, all as it should be.

[ITG]

I’d suggest you’ve missed something! I’ve done it myself. Whatever else may or may not be right or wrong with the frog juicer, if a dropper wire wiggle causes a short, let alone just a power failure, that’s an issue! Good luck with the search.

Ian

[Corbs]

The really strange thing is that it was working fine before, but this fault has just appeared. I was looking to see if a rogue track pin or something had lodged itself somewhere, but not found anything.

[smokebox]

Possible a track joint has closed up with the warm weather?

[jpendle]

On 12/05/2024 at 12:31, Corbs said:

The really strange thing is that it was working fine before, but this fault has just appeared. I was looking to see if a rogue track pin or something had lodged itself somewhere, but not found anything.

So you got a wire in the wrong place, BUT, it isn’t making contact, so no short.

Wiggle it and you get a short.

Remove that wire and do it again.

 

John P

[Corbs]

On 16/05/2024 at 23:56, jpendle said:

So you got a wire in the wrong place, BUT, it isn’t making contact, so no short.

Wiggle it and you get a short.

Remove that wire and do it again.

 

John P

I did wonder that but if we unplug that whole section (the removable section has the bit of track with the wire wiggle issue), it still shorts out on the points.

Have read somewhere about faulty boosters. If we're not getting the full 5 amps, could it be that the juicers aren't able to switch properly and are instead just shorting out?
Is there any way of diagnosing whether we are getting 5 amps out of the booster?

[garethashenden]

What happens if you unplug the frog juicer? It should result in an unpowered frog and no shorts. 

 

I had one fail recently in the same manner you've described. Even moved it to a different turnout and the fault moved too. So in my case anyway its definitely the frog juicer at fault. 

[Mallard60022]

It isn't to do with something on the Loco or Stock with 'pickups' moving over several Juicers at the same time? I have no idea what I'm talking about but a friend has had some issues with this, but on Coaches with things for lighting on the axles?

I have two 6 X out put Tam Valley Juicers on some complex X overs/Points all in the same section and close, as I am crap at wiring and they have been in place, no Booster for 8 years. I have no idea how to test one.

PHIL

 

[Corbs]

Realised it would probably help if I posted a picture of what this looks like.

 

3 tracks cross the removable section (in front of the door).

 

The frogs circled in red are shorting out when trying to switch.

 

The return loop polarity switching section (outlined in blue) also shorts out.

 

I don't think the issue is the tracks on the removable section coming into contact with those either side as we tried it even with the removable section on its own, and it still happens.

 

[RFS]

Do you have insulated rail joiners on all the frog rails?

[Corbs]

2 minutes ago, RFS said:

Do you have insulated rail joiners on all the frog rails?

 

Yes - this was all working 100% until the other day.

[number6]

With all that soldered rail on the big pieces of copper clad. I’d be looking carefully at them for a possible reason. Is that copper clad double sided? I once slit one side but not the other and put a nail through it and caused a short. 

[Phil Bullock]

3 minutes ago, number6 said:

With all that soldered rail on the big pieces of copper clad. I’d be looking carefully at them for a possible reason. Is that copper clad double sided? I once slit one side but not the other and put a nail through it and caused a short. 

You are not alone…. 

[RFS]

These are clearly Electrofrog points but I can't see where the frog is completely isolated from the switch blades. If they're not, then the frog is getting power both from the frog juicer and by the blades contacting the stock rails which could be causing a conflict. I would suggest you disconnect the frog wire from the juicer, and then use a multi-meter to check the frog is completely isolated from all adjoining rails. 

[Corbs]

On 12/05/2024 at 20:30, smokebox said:

Possible a track joint has closed up with the warm weather?

It was this!

 

I checked all the fishplated joints but it was Chris who spotted that a switch rail had contacted with the adjacent rail on the point. It alllll makes sense now. What a palaver!

Chris prised the rails apart and it's working once again.

Thanks everyone for your help with problem-solving.