Running, both DC and DCC.

[froggy]

Someone at the LHS told me I can have my track wired for DCC and also DC.If I want to run DC I just need to connect a douple pole single throw  toggle switch. Which ever one I want to use will have the power on and the other will be off.Is this true? because I want to be able to use my DC locomotives and take them off and use my DCC.

[jeffrey-wimberly]

You can do it that way. I would use a DPDT though. My layout was originally built for DC operation and was broken intop sixteen blocks with each block on it own DPDT. I can run a DCC train on one set of blocks while I operate a DC train on another set of blocks. Don't let a DCC train cross onto DC or vise versa. The decoders and/or control station don't like it.

[froggy]

If anyone's done that can they show me or tell me how to wire it?It would be wored to the Prdigy so the power would be cut off. Why can't a person turn the power off to the one he is not running?

[UpNorth]

DPDT center-off  switch right at the power packs.  Having both the DC and DCC wired and simply turning one off is simply too risky. The risk is blowing out one unit by human error.

 

[jeffrey-wimberly]

This is the way I wired my DPDT switches. If I flip the switch up, DCC goes to the block. If I flip the switch down, DC goes to the block. Placing the switch in the middle turns off power to the block.

 

[froggy]

I know now using a DPDT can kill the power to either one of them, but wouldn't it be simpler to unplug one or the other?Unplug the power to the one you don't want to use.?

[jeffrey-wimberly]

No. Just unplugging the DC unit won't help. It will still cause problems with the DCC unit. When using DCC the DC unit must be completely disconnected from the track and vise versa. The DPDT does this job well.

[froggy]

That's a good answer, The Prodigy does not have an off on switch so I imagine when I'm done running trains It is okay to unplug it?Or would you just turn off the switch? Do we need a DPDT for the DC and the DCC or just one of them?

[Vail and Southwestern RR]

Both units are connected to the switch.  The switch selects which unit is connected to the tracks.  If you have any doubts about doing this, don't do it.  You need to make sure that you understand what you are doing, or you will burn something out.

[froggy]

I only have doubts because of my questions. I want to do this, because I don't want to build a another layout for my DC.I have a label maker, so I would be sure NOT to mess anything up.I usually plan these things out before I do it.That's why I ask the questions I do.

[jeffrey-wimberly]

That's a good answer, The Prodigy does not have an off on switch so I imagine when I'm done running trains It is okay to unplug it?Or would you just turn off the switch? Do we need a DPDT for the DC and the DCC or just one of them?

You would need just one. When I flip any of my DPDT's up, that track section is powered by DCC. When I flip any of my DPDT's down, that track section is powered by DC. If I set the DPDT in the middle position, that track section isn't connected to either power source and is therefore dead. This is handy for storing locos on unpowered spurs until I need them.

[froggy]

before I found out about the DPDT swich, I was dreading about adding on to my layout. That would have been difficult to do.After the guy from the LHS told me this I was thrilled about getting this started.

[jeffrey-wimberly]

The wiring is really easy to do. With the DPDT you can have DC and DCC systems ready to go but only one of the will connected to the track at any one time.

[froggy]

I just came downstairs from the third floor. That is where my track is set up,I need a 15 degree cross over and I can connect the two tracks. I will be running two trains at once.I will have 6 sidings to park DCC locomotives and or rolling stock.

[jeffrey-wimberly]

Sounds like a good setup. I usually have two trains running at once myself, sometimes four. So that's four to seven locos running at once.

[jeffrey-wimberly]

Froggy: Check your PM's.

[dehusman]

Just make sure you don't have any DC engine on the track when you cut over to DCC or you may fry them.

Dave H.

[froggy]

How would the diagram look if I had a power pack for DC that had cab A and Cab B?I am running two DC locomotives with DC.

[larak]

How would the diagram look if I had a power pack for DC that had cab A and Cab B?I am running two DC locomotives with DC.

Almost identical. Cab a feeds one end of switch, Cab B the other and track off of the center. 

[UpNorth]

Just make sure you don't have any DC engine on the track when you cut over to DCC or you may fry them.

Dave H.

No, you will not.

David B

As DCC voltage will be present, the DC loco will sit buzing loud enough to drive you crazy till it cooks itself to death, eventually.

" To avoid heat build up in your locos without decoders, Digitrax recommends that analog locos NOT be left sitting on DCC powered track for long periods of time when they are not running.  "

 

[Vail and Southwestern RR]

Just make sure you don't have any DC engine on the track when you cut over to DCC or you may fry them.

Dave H.

No, you will not.

David B

As DCC voltage will be present, the DC loco will sit buzing loud enough to drive you crazy till it cooks itself to death, eventually.

" To avoid heat build up in your locos without decoders, Digitrax recommends that analog locos NOT be left sitting on DCC powered track for long periods of time when they are not running.  "

 

Some will, some won't.  It is not at all likely to be instantaneous.  the bigger thing you are trying to avoid is shoting the outputs of the DC system to the DCC system.  If the current output of the DC system is not limited, the DCC system is not going to be ahppy with the result. And remember, a loco crossing a boundary is shorting the systems together.

[froggy]

Now I'm confused. someone told me to use two DPDT switches because my power pack for DC will be running two locos.Some of these pictures still confuse me.Will my feeder wires for the DC be the same as the DCC?

[jeffrey-wimberly]

I don't know who told you that. The only time you'd need more of the DPDT's is if you're going to break the layout up into blocks. This could be done to isolate spurs or sidings for 'parking' locos when not in use. Multiple DPDT's would be wired the same as a single DPDT. There's nothing confusing about it. It's only confusing until you actually do it. I've given you everything I can, the rest is up to you.

[UpNorth]

As per one of his previous posts, he wanted to run  dual DC throttle (cab A/ cab B) and this requires additional  means of isolating  both DC throttles from the DCC.  So it requires 2 DPDT center-off and from these he runs wires to his cab A/B DPDT switches. From the cab A/B DPDT switches he runs his feeders to track blocks.  So it can become confusing to someone who is not familliar with the wiring. 

This requires you label  both DC/DCC DPDT center-off switches and remember to put them both on DCC or DC or risk blowing something.  The block DPDT switches will not matter in DCC operation.

If you are confused, don't risk it. 

[Rotorranch]

Would a 4PDT center off toggle work?

 http://www.mouser.com/Search/ProductDetail.aspx?qs=W18tsexzFXobHG5qKG8mpQ%3d%3d

The cabs can be hooked to one side, DCC to the other. When switched, it would disconnect both cabs with one switch.

Here's a link to more 4PDT switches.

http://www.mouser.com/Search/Refine.aspx?Ntt=*4PDT*+*switch*&N=1323038&Ntx=mode%2bmatchall&Ns=P_SField&OriginalKeyword=4PDT+switch&Ntk=Mouser_Wildcards

Rotor

[Vail and Southwestern RR]

Yep,  a 4PDT is a good solution.  Some people use a connector, so that only one system of the other can possibly be hooked up at once.

[UpNorth]

If he he found this confusing, once he sees the terminals on that switch, it should give him a good scare.

I had thought of the 4PDT on-off-on switch once I had finished my drawing. Too lazy to change it.

 

[Rotorranch]

I think this would work with a 4PDT switch:

Rotor

[n1vets333]

I didnt think it would fry them either. from what I understand a dc enginew on a dcc track will only make the engine light and vibrate while on the track with no damage being done to the train.

[jeffrey-wimberly]

Believe me, it will. I fried the motor of a MDC RS-3 with a Bachmann DCC system.