Re: Parallel track power busses
Do you have the ARs connected straight to the booster or after a circuit breaker? Some CBs are so fast that they trip before the AR can reverse polarity.
PSX-ARs are a great solution because they act as both a CB and AR. They can tell the difference between a polarity mismatch and a short.
Puckdropper
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On Tue, Jan 11, 2022 at 07:47 PM, Greg Harter wrote:
Well.......The track polarities are all now matching, and the locos run
fine.......except......
.....for the reversing loops. I have two of them, and have circuit boards
that reverse the current if there is a mismatch when a loco enters the
loop. Worked fine with the EB3s, but not the PSX's. So...Tony's told me
to get a couple of PSX-ARs for that. So I will.
Thanks for all your help, guys.
Greg Harter
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Re: Parallel track power busses
Well.......The track polarities are all now matching, and the locos run fine.......except......
.....for the reversing loops.? I have two of them, and have circuit boards that reverse the current if there is a mismatch when a loco enters the loop.? Worked fine with the EB3s, but not the PSX's.? So...Tony's told me to get a couple of PSX-ARs for that.? So I will.
Thanks for all your help, guys.
Greg Harter
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Re: DCC system resets when accelerating locomotives
Phil T,
That's amazing! I've seen bad power cords, but in my experience, they've always worked well or failed (not connected.) I've never seen one that limited the load like yours. It would have taken me "forever" to find it, too!
Don Weigt Connecticut
-- Don Weigt Connecticut
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Re: Parallel track power busses
Thanks for all the excellent advice.? I'm now going through each block to ensure polarity is aligned. ?
Greg Harter
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Re: DCC system resets when accelerating locomotives
I wanted to thank everyone who gave me ideas on how to fix this! I made some changes based on your recommendations and have improved the layout, even though the problem still eluded me.
I went over to a friend's layout while his work crew was there, and one of them had a ton of experience with NCE Power Cabs. We ran my locomotive on the layout and it worked great. He took my Power Cab home, switched out and tested the parts, and was scratching his head trying to get to the cause. Then he tried to accelerate one of his engines, and it rebooted after accelerating a little. Then he switched the power cord that goes into the outlet. BINGO!!
His power cord worked on my PowerCab perfectly. I"ve ordered a new one and should be up and running DCC soon!
Again, thanks for all of the help.
Phil
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Re: Parallel track power busses
Yes it matters.? while it's not DC it's sensitive to phase, so you basically treat it like DC.? If you reverse the phase from block to block it will short when an engines crosses the boundary.? At least that's my understanding.
Wil
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Re: Parallel track power busses
This is correct. Using a voltmeter set to read about 20V AC, the gaps in both rails ("left" and "right") should have zero or near zero volts between the same rail across the gap (left to left, or right to right), and equal voltages of about 12 to 15V for HO and other smaller gauges between either "left" rail and either "right" rail. This shows the power in the same rails is in phase across the gaps, and opposite between left and right rails in the track.
On a reversing loop or wye, only one end can match at any time, thus the need to switch the connected phases of one or the other: the reversing loop or wye, or the "main" track it meets. Im most cases, the reversing loop or wye is the smaller section and the better one to reverse.
Don Weigt Connecticut
-- Don Weigt Connecticut
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Re: Parallel track power busses
Yes it matters.? while it's not DC it's sensitive to phase, so you basically treat it like DC.? If you reverse the phase from block to block it will short when an engines crosses the boundary.? At least that's my understanding.
Wil
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Re: Parallel track power busses
Welcome to DCC. ? You want to rails to match and not be reversed, otherwise everytime an engine truck crosses the gap it will create a short back to the main power supply. ?
Use a voltmeter set to AC, to make certain both sides of the gap are the same polarity¡
?
I'm either lucky, or it doesn't matter.......
After 20+ years, I am replacing my EB3 circuit?breakers on my HO layout.? I have an NCE ProCab system.
I replaced them with six PSX circuit?breakers.? I've wired it (hopefully) correctly.? And have run a loco through three of the blocks powered by the PSX units, with no problem.
I know polarity doesn't matter with AC circuits, and there's nothing but AC circuits?on the six blocks........but.........when a loco goes from one block to another, and the AC rails are reversed in the new block, does it matter?
Wish I knew more about this stuff, but at 80, I'm still learning!
Greg Harter
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Re: Parallel track power busses
Yes.? Thank you for the correction and clarification.
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Re: Parallel track power busses
Duff or Polly,
That's almost correct as far as it goes, except for the statement about auto-reversing. Only ONE of the two blocks would need one. In fact, auto-reversers that are adjacent will not work happily together unless there is a piece*() of track between them that does not autoreverse.
Wouter
(*) volumes have been penned about how long a "piece" is, often when the subject is string. This is not the place for that discussion.
Assuming I am understanding correctly, polarity does matter with AC, but not the same way for train operation.
Let's consider two of the? six blocks for simplicity, the train rinning from left to right, and crossing from one block to the other.? The rails in each block are marked + and -.? Yes, for AC, they alternate, but at any instance of time, the the labels are as shown.
In this first example, as the wheels cross the gap, they connect + to +, and - to -.? No problem.
+ ____________________________________? ________________________________ +
- _____________________________________ _________________________________ -
In this second example, the wheels connect + to -, and - to +.? This is a short circuit.? And is what happens with reversing loops.
+ _____________________________________ ________________________________ -
- ______________________________________ ________________________________ +
If each block has its own auto reverse, things will correct themselves, and it may not matter.? However, if there are no autoreversers, a short will be detected.
This is how I understand it, given my limited experience with DCC.
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Re: Parallel track power busses
Assuming I am understanding correctly, polarity does matter with AC, but not the same way for train operation.
Let's consider two of the? six blocks for simplicity, the train rinning from left to right, and crossing from one block to the other.? The rails in each block are marked + and -.? Yes, for AC, they alternate, but at any instance of time, the the labels are as shown.
In this first example, as the wheels cross the gap, they connect + to +, and - to -.? No problem.
+ ____________________________________? ________________________________ +
- _____________________________________ _________________________________ -
In this second example, the wheels connect + to -, and - to +.? This is a short circuit.? And is what happens with reversing loops.
+ _____________________________________ ________________________________ -
- ______________________________________ ________________________________ +
If each block has its own auto reverse, things will correct themselves, and it may not matter.? However, if there are no autoreversers, a short will be detected.
This is how I understand it, given my limited experience with DCC.
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Re: Parallel track power busses
On Wed, Jan 5, 2022 at 05:30 PM, Greg Harter wrote:
I know polarity doesn't matter with AC circuits, and there's nothing but AC circuits?on the six blocks........but.........when a loco goes from one block to another, and the AC rails are reversed in the new block, does it matter?
Hi Greg. Yes, it matters. If the rails are connected backwards in one power district compared to the next it will create a short circuit when the wheels cross the gap. Even with AC, a short circuit is still a short circuit.? If your trains run around the layout with no hesitation and you're not tripping the PSXes then everything's OK. Tim Rumph Lancaster, SC
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Re: Parallel track power busses
I'm either lucky, or it doesn't matter.......
After 20+ years, I am replacing my EB3 circuit?breakers on my HO layout.? I have an NCE ProCab system.
I replaced them with six PSX circuit?breakers.? I've wired it (hopefully) correctly.? And have run a loco through three of the blocks powered by the PSX units, with no problem.
I know polarity doesn't matter with AC circuits, and there's nothing but AC circuits?on the six blocks........but.........when a loco goes from one block to another, and the AC rails are reversed in the new block, does it matter?
Wish I knew more about this stuff, but at 80, I'm still learning!
Greg Harter
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Re: Parallel track power busses
I've been replace 12 gauge with 14 as I rewire to support
signaling on a 4-track main, but have had no problems.? Indeed, in
one section, I've even been able to get away with exceeding the
maximum recommended buss length with no problems.
On 1/1/22 8:22 AM, Steve Hubbard via
groups.io wrote:
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Hmmm!? #10 wire is way overkill, harder to work with and
expensive.? ?Just sayin.
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Re: NCE Switch-Kat address programming
AFAIK, you don't "program" the Switch Kat's address via a normal DCC programming operation.
IIRC, there is a jumper on the Switch Kat, that if you short it, then send a switch command to the desired address you wish to use for that Switch Kat, and then disconnect the jumper short, the Switch Kat will remember that address as its own.?
The Switch Kat instructions describe the address-assignment operation.
-- Andy - Arlington TX
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Re: Parallel track power busses
Steve,
You are probably correct. At the 10-12 level I find little difference in the workability and there is a slight decrease in voltage drop. I'll just need to see what the local electrical supply has.
Thanks,
Michael
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Re: Parallel track power busses
Hmmm!? #10 wire is way overkill, harder to work with and expensive.? ?Just sayin.
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Re: Parallel track power busses
I've found auto parts stores are good sources of heavy stranded wire, and the larger currents and lower voltages of automobile wiring make their wiring supplies well suited to our similar model railroad requirements.
Don Weigt Connecticut, USA
-- Don Weigt Connecticut
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Re: Parallel track power busses
Hi Dale,
Just checked and I think this (connecting remote indicators) will work very nicely. An excellent alternative.
However, if I use the second method (run a 10AWG track buss to the right then split to the breakers) I'll need to find a source for 20' of yellow and brown stranded 10AWG. This is because the colors for this Power Bus are yellow and brown.
The big box stores won't be of help but perhaps the local electrical supply will have what I need.
Thanks,
Michael
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Tim
Michael Boyle