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Richard, Welcome. Glad to see your response. Remember this site is for all scales and all your questions will be answered here. With nearly a half million views there is no site like this one; modelers helping modelers. So join us anyway you want. Happy New Year, Jim
PS. Next adventure? Probably trying to live to 80 would be my best guess!
Thanks fellows and Happy New Year and Birthday to this thread.
The layout is nearly finished. I am having a difficulty with wiring as my brain seems to be draining away. I have a Micro Engineering turnout that has a 'dead' frog. On purpose this. It is isolated from all the other track on the turnout. If I run my DC HO test loco over the frog it stops dead. The frog is DCC compatible, it wouldn't stop a loco that is big enough to cross the frog I'm guessing. My question is: How do I electrify the frog for DC so that the polarity of the frog will always allow DC engines to go through? There is a place to add a wire, but it seems like there should be more to this. Anyone? Jim
If you are just using the contact from the points of the moveable rails against the stock rails to electrify them (and change their polarity accordingly), then just connecting a wire from the frog to the point rails should also change the frog's polarity to match the direction of travel.
Toot, Thank you. So do I need any type of toggle switch to control polarity if the train is coming into the turnout say from the siding? Let's say the loco went onto the turntable and turned around to come back? Jim
Toot, Thank you. So do I need any type of toggle switch to control polarity if the train is coming into the turnout say from the siding? Let's say the loco went onto the turntable and turned around to come back? Jim
As the points are acting as the power switch for the tracks, no other switch is necessary. With a DC loco, you would only need to have the cab's direction switch set to the direction of travel, and this would apply also to the turntable scenario. With DCC, the direction doesn't need to be changed on the cab because the loco's decoder decides which way is forward or reverse in accordance with the cab. Even if you physically lifted the engine off the track and turned it around, it would still obey it's set direction. It's only necessary to have reversing switches (with DC or DCC) where there is a situation like a closed reversing loop.
This matter of track polarity in regard to DC control, where we actually change the track's polarity to change our loco's direction and DCC control, where the polarity (for what it is, being a different wave form) is always the same regardless, and we use a digital signal to achieve that instead, is one of the hardest things for previous DC users to get their heads around. (Took a while for the light bulb to shine in my brain, needed an LED upgrade)
Okay Toot, I will follow your directions the best I can.
ISSUE TWO: I will have both DC locos on this layout, and I will have some DCC locos. What will I need or have to do to run DC and DCC separately of course. Jim
If you are wanting to run a DC engine on a dcc track, you can only run one at a time. With dcc engines you can run as many as your power supply can handle. Hope that helps, Dan
If you are just using the contact from the points of the moveable rails against the stock rails to electrify them (and change their polarity accordingly), then just connecting a wire from the frog to the point rails should also change the frog's polarity to match the direction of travel.
Actually what I said there about changing the tracks polarity was incorrect, it doesn't. All the points are doing when they shift from one direction or the other, is picking up the power and polarity, from whichever point is in contact with the stock rail. The other stock rails in the turnout will be receiving power from the track supply to those rails. In the case of a metal frog, it is isolated by gaps from all the other rails and would have no power at all, but by connecting that wire from it to the points, it becomes powered up with the polarity that is associated with whatever point rail is in contact with a stock rail.
If memory serves, you'll need a DPDT toggle switch to control polarity of the frog to coincide with the points directions. It's been 30 years since I wired a layout, but I believe that's correct....I wouldn't rely on the points for power directions.....often to unreliable ?
Thanks again. Toot, I get it. Dan, this layout only has room for one train so whether it is DC or DCC number of locos is not an issue.
Welcome Logger Mike. Good to see a new poster. So I will need a DPDT to toggle between DC running and DCC running. I think I can do that. I will have separate wiring for DC and DCC so other than knowing where to put the toggle I'm beginning to understand this. Also, there is this one turnout and wiring to points will probably suffice with my skill level.
Here is a photo of the bottom of the turnout. The little hole on the left will need two wires coming out of it to each point?
The points are the more gold color rail on right side of the photo.
I'm sort of stumped concerning the wires connecting the track however? Thanks Jim PS The frog is metal
Jim , a wiring expert I am not but don't those jumpers between the main and diverging rails route the power , making power transfer at the rail points a non issue?
Yes. By adding those jumpers you guarantee power to the diverging rails and not rely on the points picking up the power simply by touching the rail, which can be iffy.
The jumpers Walt's referring to are those short pieces of soldered in wire, connecting the outer stock rails in your photo and they are making the connection/s to the frog (there's no sign of any cuts any closer to the frog). And as Jim has said (the other Jim that is) they make relying on the point/s contact for supplying power to the frog and tracks within the turnout a non issue. Taking the position of the moveable rails in the photo, the "switch" is in the straight through position. The 2 outer stock rails are being supplied with power (polarity determined by which way your controller/cabs direction switch is facing in DC, just for the sake of simplicity).
What is happening here, is that the track and frog are being supplied with power for running a train on the straight through track. We'll assume the top outer stock rail is positive and the inner (bottom rail) is negative. With the point closed (as it is), the frog and it's attached fixed rail and the point rail are receiving negative polarity. Train runs through, no loss of power, no shorts.
We now switch the points so the diverging rail's point is in contact with the top positive rail. This breaks the frog's contact with the negative rail and supplies it with positive current via that jumper (and maybe the point's tip). The train can now enter or leave through the turnout, having power throughout the move.
Using DCC as the power supply doesn't alter any of the above.
