[solved] Problem caused by DDX/ORD-3 ?

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[solved] Problem caused by DDX/ORD-3 ?

Postby agre30 » 18.03.2013, 21:45

This weekend I changed a Märklin locomotive by placing a Hamo magnet and an ESU Lokpilot Basic DCC decoder. When this train runs around my track the servo's connected to the Digirails servodecoders are going crazy. They are moving from left to right and back at high speed so I cannot use this locomotive because my switches are unreliable.

Could the problem be cause by de DCC signal on my track, which is generated by the DDX software station and connected through an ORD-3 booster?

Albert.
Last edited by agre30 on 10.05.2013, 11:47, edited 1 time in total.
Albert,
Märklin 3-rail
Lubuntu 16.04 (server and client) / TamsMC - Booster B-2 / HSI88 / S88N
Stoom / steam / dampf / diesel / E-loc
agre30
 

Postby rjversluis » 21.03.2013, 14:29

Hi Albert,

you did wrote the answer to your question yourself.

...Hamo magnet and an ESU Lokpilot Basic DCC decoder. When this train runs around my track...
Best Regards, Rob.
:!: PS: Do not forget to attach the usual files.
:!: PS: Nicht vergessen die übliche Dateien an zu hängen.
[ macOS - Linux] - [ N: CBus - CAN-GCA ] - [ 0: RocNetNode - GCA-Pi ]
rjversluis
Site Admin
 

Postby LDG » 21.03.2013, 15:13

Hi Albert,

are your servo cables bundled with track power cables or directly next to them in parallel ?

We had similar effects with a loco in our club.
Servo connected to ESUSwitchPilotServo. With one loco the switch servo just ahead of the loco was flipping like crazy. After moving the 3-pole servo cable 10cm away from track power everything was OK!

Reagrds,
Lothar
LDG
Site Admin
 

Postby agre30 » 21.03.2013, 17:59

Rob, Lothar,
Thanks for your reply.


@Rob: strange thing is that I have more loco's with Hamo magnet and ESU LOPI decoder and they don't cause problems.
In the wiki I read: 'DDX is not able to deliver the quality of real Command Stations and problems can be expected using it', so I thought it might be a combination of loco and DDX.

@Lothar: The servo-decoder is connected to a 32VA Märklin power supply and the 2 cables for the DDX signal are connected to the track as close to the decoder as possible. The decoder is mounted about 5 cm beneath the track.
Do you mean to say that when I move the decoder away from the track the problem might be solved?

Greetings,
Albert.
Albert,
Märklin 3-rail
Lubuntu 16.04 (server and client) / TamsMC - Booster B-2 / HSI88 / S88N
Stoom / steam / dampf / diesel / E-loc
agre30
 

Postby rjversluis » 21.03.2013, 18:25

Hi Albert,

servos are very sensitive and are not used to the Märklin motor distortion.
Most Märklin 'riders' are using the good old coil switch motors which are not sensitive at all. ;-)

OK, now a bit serious.
Keep servo cables as short as possible and keep distance from the tracks. (As Lothar wrote.)
Best Regards, Rob.
:!: PS: Do not forget to attach the usual files.
:!: PS: Nicht vergessen die übliche Dateien an zu hängen.
[ macOS - Linux] - [ N: CBus - CAN-GCA ] - [ 0: RocNetNode - GCA-Pi ]
rjversluis
Site Admin
 

Postby agre30 » 21.03.2013, 20:53

Hi Rob,
I blamed the servo decoder so I replaced the Digirails by an ESU switchpilot servo, and moved the decoder away from the track but without effect. So I think you are right: the servo's are too sensitive for the distortion caused by the Märklin motor.

Thanks for your help.

Albert.
Albert,
Märklin 3-rail
Lubuntu 16.04 (server and client) / TamsMC - Booster B-2 / HSI88 / S88N
Stoom / steam / dampf / diesel / E-loc
agre30
 

Postby RainerK » 22.03.2013, 06:32

Hi Albert,

a possible solution to Your problem:
Take a piece of aluminum foil from the kitchen, wrap it around the servo cable over the full length
and connect a piece wrapped around it bare wire to the ground connection of the cable at the decoder.

Best Regards
RainerK
Best Regards, es grüßt RainerK

DCC++ with Arduino Uno / Motor shield and LocoNet GCA85, 50, 93 and 136. Special interests: DIY electronic assemblies. http://www.rainermoba.blogspot.com
Planning replace the coincidence by the mistake
RainerK
 

Postby agre30 » 22.03.2013, 08:54

RainerK wrote:Hi Albert,
and connect a piece wrapped around it bare wire to the ground connection of the cable at the decoder.
RainerK


Hi Rainer,
thanks for the advise. I will give it a try but there are 4 cables on the decoder. 2 of them are connected to the track and 2 are connected to the power supply. Which one of them is the ground connection?

Albert.
Albert,
Märklin 3-rail
Lubuntu 16.04 (server and client) / TamsMC - Booster B-2 / HSI88 / S88N
Stoom / steam / dampf / diesel / E-loc
agre30
 

Postby RainerK » 22.03.2013, 09:28

Hi Albert,
agre30 wrote:... but there are 4 cables on the decoder. 2 of them are connected to the track and 2 are connected to the power supply. Which one of them is the ground connection?

RainerK wrote:... wrap it around the servo cable over the full length ...

... and there is mostly the darkest wire connected to ground.
For exactly information about that You need to consult the manual of the servo and/or the decoder.

Best Regards
RainerK
Best Regards, es grüßt RainerK

DCC++ with Arduino Uno / Motor shield and LocoNet GCA85, 50, 93 and 136. Special interests: DIY electronic assemblies. http://www.rainermoba.blogspot.com
Planning replace the coincidence by the mistake
RainerK
 

Postby agre30 » 22.03.2013, 16:37

Hi Rainer,

Sorry, I misunderstood. Now it's clear. It's the cable between servo and decoder. Thanks for your help. I will let you know about the result.

Greetings,
Albert.
Albert,
Märklin 3-rail
Lubuntu 16.04 (server and client) / TamsMC - Booster B-2 / HSI88 / S88N
Stoom / steam / dampf / diesel / E-loc
agre30
 

Postby agre30 » 23.03.2013, 19:48

Hello,
I'm learning by doing :D
I mounted a permanent magnet in a Märklin BR81 and BR03 but did not place the choke coils as provided by ESU. I was told they are not needed anymore.
(not on this forum of course).
I should have known better. To be sure the problem with the servos was not caused by the modified locos I placed the choce coils. This solved the problem. Both trains travel around without problems.

Still I will try the solution given by Rainer because sometimes when I lay my hand on the track or replace a wagon or loco one of the servos moves without reason.

Thanks for your help and I will keep you informed.

Albert.
Albert,
Märklin 3-rail
Lubuntu 16.04 (server and client) / TamsMC - Booster B-2 / HSI88 / S88N
Stoom / steam / dampf / diesel / E-loc
agre30
 

Postby agre30 » 10.05.2013, 11:47

The problem with the servo's is solved. For several weeks I didn't have any problem.
I placed a ferrite ring around the cable of the servo that caused most of the problems.
Albert,
Märklin 3-rail
Lubuntu 16.04 (server and client) / TamsMC - Booster B-2 / HSI88 / S88N
Stoom / steam / dampf / diesel / E-loc
agre30
 

Postby Besra » 10.05.2013, 13:05

Hi Albert,

it is frequently discussed on forums whether or not to use the choke coils. Sometimes people argue it makes no difference to the loco. Of course it does not (or better to say: it should not).
But it can effect the rest of your layout including other locos, accessory decoders or your neighbour's satellite receiver or cordless telephone... ;)

At least now you know what these little things are good for :D

Best regards
Besra
Maerklin H0, DCC and MM, Intellibox (I) via ULNI, Booster Tams B4, Throttle Digitrax UT4, LocoNet.
Loco decoders: Zimo, Uhlenbrock, Maerklin & ESU.
Rocweb, Win10 32bit & 64bit
Besra
 


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