LGB 22711 U class smoke problem

[Alpineandy]

The loco is with fitted with factory decoder, the smoke is a 5 volt unit working through the decoder.
It works ok on analogue but is not working correctly when on dcc.
I have checked the voltage at the feed posts and I am only getting 2.5 volts (no load) on dcc.
any ideas ............?:thinking:
Ta in anticipation

 

[funandtrains]

I've been told that if you only run on DCC is is best to change the smoke unit for a 24V one and set the decoder output to this as then the power runs straight through and reduced the load on the decoder which would stop this problem as well.

 

[mike]

haveyou tryed switching it on,useing a funtion key.ie f5

 

[funandtrains]

If you are using a non LGB DCC system some LGB decoders can have problems with all functions working.

 

[ntpntpntp]

I assume you used a dc voltage range when you measured the 2.5v? Does the 2.5v you measured change if you turn the smoke function on/off ?

You say the smoke works ok on analogue dc: does it (and the loco) work ok in both directions? This isn't a problem with the main rectifier in the decoder I hope?

 

[Alpineandy]

Thanks for all the suggestions but i've sussed it after doing a bit of googling.
I have set CV56 to a value of 9 which is now giving me 5 volts on the output posts and good smoke..........

 

[ntpntpntp]

Curious that changing the voltage cv seems to be the solution. I'd have expected that you'd have the same under-voltage problem on that function under analogue dc before making the change.

Glad you appear to have sorted it!