# Help - Speed drops when lights are on



## kdtsolutions (Jan 20, 2008)

I thought this should be a seperate post.  I am using an LGB 55027 3 A decoder.  When the lighting funtion is turned on the locomotive speed drops.  The locomotive requires about 3 more speed steps to start.  Full speed on the drivers drops from about 166 RPM to about 150 RPM (engine on blocks).  This drop happens even if nothing is connected to the decoder except track and motor leads.  The two settings that may effect this are as follows:

1)  I had to change CV9 for a lower frequency or the engine would not operate.  I am at 400 Hz with an accucraft k28.  

2)  I also set the voltage at the lighting terminals at 5V.  I am going to check this and see if it has any effect.

Thanks!

Mark


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## stanman (Jan 4, 2008)

Just a guess, but perhaps your power supply is on the light side. What are you using for power?


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## kdtsolutions (Jan 20, 2008)

I am using a 32 A regulated DC power supply from Shourtline with a Massoth 1210z 12 A Central station and Massoth 1203 12 A booster.  I don't think it is power because I have never noticed this on other engines.  I have done quite a few DCC installs, but this engine/decoder combination has been challenging.  The strange thing is I have disconnected all funtion leads on the decoder and still have the problem.

Thbanks for the idea,

Mark


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## rwbrashear (Jan 5, 2008)

Hi Mark-

Check CV#59, _function button assignment for 'shunting' or 'half-speed' mode_.  You can map this function to buttons 1-8 with MTS.  Try setting the value to [0] to disable the shunting mode.

Best regards,
Bob


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