Model Railway Forum banner
1 - 4 of 4 Posts

·
Registered
Joined
·
3 Posts
Discussion Starter · #1 ·
Hi,
I have a Liliput L.170110 Class 99 0-6-2 Tank Loco `Zillertalbahn`. I have fitted a cTelektronik DCX74z decoder to this loco. The loco was well run in on Dc before I fitted it and ran okay. After fitting the decoder, I programed it with the Roco Multimaus, but I was not sure if I had done this correctly, but when I tried the loco it ran okay. Whilst altering some menu settings in the multimaus, the decoder was getting quite warm while the loco was stationary. I ran it for a while more and it was okay, but when I tried it later, it would not work and I could not program the decoder. Have I burnt out the decoder, or has anyone any ideas, as I am new to DCC. I have the Roco Digital Starter set, and the loco with the start set is oaky. Thanks
Martin
 

·
Just another modeller
Joined
·
9,983 Posts
QUOTE (Metroman @ 14 Jul 2008, 06:18) <{POST_SNAPBACK}>Hi,
I have a Liliput L.170110 Class 99 0-6-2 Tank Loco `Zillertalbahn`. I have fitted a cTelektronik DCX74z decoder to this loco. The loco was well run in on Dc before I fitted it and ran okay. After fitting the decoder, I programed it with the Roco Multimaus, but I was not sure if I had done this correctly, but when I tried the loco it ran okay. Whilst altering some menu settings in the multimaus, the decoder was getting quite warm while the loco was stationary. I ran it for a while more and it was okay, but when I tried it later, it would not work and I could not program the decoder. Have I burnt out the decoder, or has anyone any ideas, as I am new to DCC. I have the Roco Digital Starter set, and the loco with the start set is oaky. Thanks
Martin

***Hello Martin

The simple wiring rules are:

(1) Both motor brushes must be totally isolated from both rails.
(2) Remove any suppression components from the loco
(3) insulate all decoder wires that are not physically connected
(4) where possible replace any incandescent bulbs with LEDs to remove possibility of failure due to over voltage.

Re your CT decoder, it may well be dead...

A decoder getting warm while the loco is stationary is indicative of a wiring issue... Perhaps an unseen path for track current to get where it shouldn't be - to the brushes.

I cannot remember but you may be lucky & the CT decoder may have a protection circuit that triggers a CV change when it is overheated and turns the decoder off (Some Lenz have this too) Look carefully through the manual and if U cannot find it then try a decoder reset which will cancel the turn off, return decoder to address 3 and also reset all other CV's of the decoder (if its still alive)...

How to test for perfect motor isolation:

**Remove both decoder wires from the motor brushes.
**Place the loco on the track.
**Set your meter to OHMS and a low scale (1k or lower).
**Place one meter probe on the track and then touch the other to each motor brush in turn.

There should be NO reading at all if the brushes are correctly isolated from the track. If there is any reading at all then you will have to evaluate and find a way to isolate that motor brush totally.

regards
Richard
DCCconcepts
 

·
Registered
Joined
·
3 Posts
Discussion Starter · #3 ·
QUOTE (Richard Johnson @ 14 Jul 2008, 04:33) <{POST_SNAPBACK}>***Hello Martin

The simple wiring rules are:

(1) Both motor brushes must be totally isolated from both rails.
(2) Remove any suppression components from the loco
(3) insulate all decoder wires that are not physically connected
(4) where possible replace any incandescent bulbs with LEDs to remove possibility of failure due to over voltage.

Re your CT decoder, it may well be dead...

A decoder getting warm while the loco is stationary is indicative of a wiring issue... Perhaps an unseen path for track current to get where it shouldn't be - to the brushes.

I cannot remember but you may be lucky & the CT decoder may have a protection circuit that triggers a CV change when it is overheated and turns the decoder off (Some Lenz have this too) Look carefully through the manual and if U cannot find it then try a decoder reset which will cancel the turn off, return decoder to address 3 and also reset all other CV's of the decoder (if its still alive)...

How to test for perfect motor isolation:

**Remove both decoder wires from the motor brushes.
**Place the loco on the track.
**Set your meter to OHMS and a low scale (1k or lower).
**Place one meter probe on the track and then touch the other to each motor brush in turn.

There should be NO reading at all if the brushes are correctly isolated from the track. If there is any reading at all then you will have to evaluate and find a way to isolate that motor brush totally.

regards
Richard
DCCconcepts
Hi,
Thanks for that. I will try what you have said today. Although there was a stage where the decoder was a little bit warm, but then it would not run. Thanks
Martin
 

·
No Longer Active.
Joined
·
13,319 Posts
QUOTE (Metroman @ 13 Jul 2008, 23:18) <{POST_SNAPBACK}>I have a Liliput L.170110 Class 99 0-6-2 Tank Loco `Zillertalbahn`.
Hi Martin,
Our experience with these locos is varied - they usually very well & draw little current or you do get a few that have indifferent motors - usually cured by a good stripdown paying particular attention to the commutator & the gaps. AFAIR they should not draw more than .2A

Hope this helps.
 
1 - 4 of 4 Posts
Top