Programming 101–Ops Mode

I’ve frequently commented on ops mode programming and I use it almost all the time no matter whether I am using a throttle or DecoderPro to program decoders. Ops mode programming was introduced on Wangrow System One command stations about 1995 to allow operators to change features like momentum and other features on the fly. I remember the late Don Wangrow telling me how he wanted his System One customers to be able to back a locomotive up to a train, couple up, increase the momentum using ops mode, and proceed with the feeling that it is pulling a really heavy load. Many new decoders now have this change in momentum built in to a function button setting.

Times have changed and now one of the big advantages of ops mode programming is that because it is done on the main tracks it is able to use the full voltage and current available. This means there are likely to be fewer problems when programming sound decoders and when keep alive circuits are installed. These devices are power sinks because they have large capacitors that must be charged up. On the service mode track, power is only applied when a programming command is being sent. As a result the capacitors may not be fully charged and they siphon current that normally would go to programming. They can also interfere with the read back capability.

This is further complicated by the fact that only 250 mA is available on the service mode track and the voltage may be inadequate. However on the main track since power is always on, the capacitors stay charged and there are fewer problems. This makes ops mode programming more reliable. This is enough of an issue that decoders like LokSound, which program best with 13 volts are more reliably programmed. ESU also recommends removing keep alive circuits when using service mode programming with LokSound decoders and I suspect this would help with other brands as well.

Another advantage of ops mode is the programming commands are only sent to the address of the decoder you are programming, essentially eliminating the chances of programming other locomotives. However, there is one exception to this. If you enter an address of ”00” the commands will go to all decoders, so be careful what address you enter. The other advantage that I really like is the ability to test the effect(s) of changes you make to CV settings. This makes it very easy to test a bunch of different speed curve settings when speed matching or when changing sound volumes.

To get around the problem of not being able to read CV settings I usually work from DecoderPro and therefore can see the value I last programmed into the decoder. As long as I don’t make any changes using just a throttle and always save my changes before closing the locomotive file, I don’t need to be able to read the CVs. If I am using ops mode programming with a throttle such as with speed matching I keep a notepad handy and write down the changes in CV settings as I proceed. When I am satisfied I then enter the final values into the DecoderPro file to keep my information up to date. It may take a few extra steps, but it gets the job done.

One comment

  • Benjamin (Ben) McCall

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