PowerPoles not always easy

[Zox]

I spent about two hours on this diagram in CorelDraw tonight, most of it drawing the PowerPole connectors. They may be easy to hook up, but they're a right royal pain to draw...



At least this way I don't have to wonder if I'm violating anyone's copyright with a recycled image. And it's a lot clearer than the photographs I've attempted.

[bicknell]

That's a great drawing.

[mmyers]

They look good. Especially tough with orthographic projection.
I've been known to borrow them from here:
http://capitolcityntrak.org/images/PP-module.jpg
http://www.cuttergraphics.com/N-trak/DCC-RP2.jpg
http://www.cuttergraphics.com/N-trak/PP-R2-Corners.jpg

Martin Myers

[mmyers]

Bob,
 My question on your drawing is: Why the barrier strip?
With Powerpoles, you can swap the housings around to change configuration so the extra connection and resulting break in the bus really isn't needed. No adapters are needed as long as the next module also has Powerpoles. That was one of the "selling points" of the NTRAK RP.

Martin

[Zox]

Martin,

There are three reasons for the terminal strip at the interface.

1. Most of our existing modules have them, as a holdover from our original wiring system.

2. They keep the pigtails in a fixed relationship with the tracks, which makes it more difficult to accidentally cross-wire the mains.

3. They act as a solid anchor point for the wiring, lessening the possibility that an errant pull will tear off the entire harness.

We're not as concerned about the occasional break in the bus as NTrak is, since we're still running DC with block control, and we don't have to worry about hundreds of feet worth of control runs.

If we ever find ourselves in a situation where continuity is an issue, the plan is to build an external, heavy-gauge "bypass" bus that can tee back in every so often. But that's unlikely to happen, given that our two-track modules can't function as part of an NTrak mainline.

[Walkercolt]

Heavy "euro-strips" that'll handle 10 gauge wire work fine for DCC, and make wiring feeders easier, and provide a "test-point" for trouble-shooting. We've "idiot-proofed" our Power-Poles at each end of the newer modules.  Before Power-Poles I was using some Molex connectors to "idiot-proof" complex connections between "dedicated modules". I like test-points. Checking soldered and taped connections on my back at the St. Louis show proved my point on terminal strips. On our 40'x60' layout, the euro-strips add about .01 Ohm loss by my Fluke on the lowest range. The 250' of #12 stranded(Monster Cable..."over-qualified", but we got it "close-out" at a big-box store) has about 3.3 ohms resistance on the roll, and most all DCC systems recommend a booster/repeater every 60'. You CAN push that, but if it won't pass the "penny test"(lay a penny across the rails and it should over-load and shut-down), you will have problems. We played "Beta-testers" for Digitrax at Louisville, and we all learned some things. Big layouts also MUST have a 12 gauge ground wire on the throttle controllers(Loco-Net or equivilent) or you get electrical "noise" problems. And Cat 5 or 6 wiring won't work on Loco-Net. Just plain old 6 conductor telephone cable is what's needed. And Digitrax, NCE and Easy-DCC can play together, but don't expect it to be easy.

[DKS]

Nice illustration. Clean and easy to follow.

[lashedup]

Big layouts also MUST have a 12 gauge ground wire on the throttle controllers(Loco-Net or equivilent) or you get electrical "noise" problems.

Can you clarify this a little more? When you say 12 gauge ground wire on throttle controllers, are you talking about throttle panels?

The war story discussions running DCC on big modular setups is good stuff.

Thanks,

-jamie

[Iain]

Yeah, DCC at Louisville was a bear.

Powerpoles did make hookup easier.  Luckily the spot were I was short-finding did  have terminal strips, making life much simpler.

[mmyers]

Big layouts also MUST have a 12 gauge ground wire on the throttle controllers(Loco-Net or equivilent) or you get electrical "noise" problems.

Can you clarify this a little more? When you say 12 gauge ground wire on throttle controllers, are you talking about throttle panels?

The war story discussions running DCC on big modular setups is good stuff.

Thanks,

-jamie

It's recommended that a heavy 14 ga or better "ground" wire be connected from all boosters, PM42's to the command station. At Louisville, they had at least one reel reel of 14awg which is the size that John Wallis spec'd. The "ground" is actually a larger version of the common on pins 2 and 5 of a loconet cable. If the system is connected to house ground it should be connected at only one point. The command station is the best choice. This avoids ground loops.

When we did the testing for the NTRAK RP, we found that one way distances of up to 80 feet of modules with the resulting number of Anderson powerpoles between modules gave reliable DCC operation and short protection. Actually 100+ feet worked. We decided to use 80% of that to allow for the two feet of extra cable that is required for each 4 foot module.  Tests were done using 12awg stranded cable with powerpoles only, cinch only, and combinations of the two. Some were brand new, none were more than two years old.  All powerpoles yielded the least resistance. All tests were done using a continuous bus for each module run of 6 feet to allow for the extra foot at each end for the tails.

The hardest part of using the 12 ga wire is attaching feeders. The method I prefer is to tap the bus once in the center with 16 ga wire and run that tap to terminal strips or tag board. Connect the track feeders to the terminal strips. This means soldering to the heavy bus only once per wire and still gives a point to easily connect test equipment for trouble shooting and a simple method to correct mis-wired feeders.

Martin Myers