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DCC Power Zone- PM42 Issue and Loconet problem

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  • Member since
    September 2013
  • 14 posts
DCC Power Zone- PM42 Issue and Loconet problem
Posted by BrendanM on Wednesday, January 7, 2015 9:18 PM

Hi-

I'm having a few issues with Digitrax PM42 power zone boards and loconet errors cause by the throttles. The PM42's are shorting each other out. Sorta.

 

First- The throttles create the 9 beep DCS100 transmit failure (there is a device blocking proper message action on LocoNet) when plugged into loconet when the system is turned on. When I unplug all throttles the 9 beep startup message goes away.. Any thoughts on why?    

One would think that Digitrax own throttles wouldn't create a loconet blocking message. The PM42's, UP5's, UR92, and DS64's don't cause the errors and they are plugged in all the time. This isn't a big deal but an annoyance.

 

Onto the PM42's- First let me explain how everything is set up. There is a DCS200 comand station and one DB200+ powering everything. Each has their own power supply with a ground.

These boosters then are connected to Acculites PM42 Breakout Boards. I use both power inputs (one set from the main command station, one set from the boaster)- I figured this would be easier on the boards instead of using the jumpers with one input power. If your unfamiler with the breakout boards- search them and you'll see what I mean... they use the 2 sets of inputs (or one with a jumper terminal) for the inputs on the PM42's- input one powers zone 1 & 2 (PM42), input 2 powers 3 & 4.

The PM42's are connected to these acculites boards. Each PM42 has its own power supply- all 14v radio shack type- and is connected through the breakout board connections; along with a ground that is connected to the booster and command station- all grounds run to single connecter befor going to command and booster. The loconet cables (all tested) daisy chain from command--booster--UR92--10 DS64's--5 PM42's--10? UP5's. Going out loconet B on command station there is another 5 UP5's if that means anything. I have all PM42's set to "faster" detection with 3 amp limit for the most part; along with all of them addressed (Easier to program using Loconet-checker).

In total there are 5 boards.

And onto the problem--Normally when one zone shorts out- the rest do not. What seems to be happening is when one zone shorts out- it will cause shorts in other zones almost randomly. So for instance- zone 18 has a short- it will bring down zone 7, 11, 15, 17, and 20. These numbers of zones shorting will vary-this is just an example. Almost always- it will take out 2 more zones on the same board however (in this example 17 & 20).

If in the middle of the short you disconnect the ground and loconet the shorts in 7, 11, ,15 17 and 20 will clear. Short 18 or whichever zone on that same board with loconet and ground disconnected- only it will short as they are supposed to. I've tested each bored without ground and loconet completly seperate with a normal edge connector and seperate tracks and they all function normally. I did this before I realized loconet and ground was causing the other zone problems (I thought I had wiring crossed somewhere- I didn't).

So what would cause this and how do I fix it?!!?? I always thought you needed to have the ground connected and I would like to keep them all connected to the loconet so I can change the allowable output amps (for when more stuff is running) quickly- computer programing is much much faster and easier. Digitrax tech support wasn't much help..

 

Thanks for any help I can get!!!  Normally I can figure out most problems but this is getting frustrating cause it really isn't making sense..?..!!!!...! 

Also sorry for the long post, I wanted to make sure no detail was missing. :)

  • Member since
    February 2002
  • From: Reading, PA
  • 30,002 posts
Posted by rrinker on Thursday, January 8, 2015 4:14 PM

 First of all, you need to unplug everything from Loconet and start with the bare minimum - booster to command station, and plug in a throttle, and then gradually add back all the other stuff to find where the problem is. You likely have a bad loconet cable or bent pins in one of the UP panels or maybe one of the other devices.

 The beeping on startup is low loconet power - how many throttles do you have plugged in? Do you have power to any of the UP5s? After 3 or 4 throttles plugged in, there is insufficient power. That's why the UP5's have coax power jacks in the side. Do NOT follow the instructions for daisy chaining them. You CAN power more than one UP5 per power supply, but run a power bus and tap off it and put coax power connectors on each feed to plug in to the UP5. Power all of them, that way you won;t have wierd issues that occur only if several operators gather in one area but everything works fine at other times.

 If the PM42 problems happen only when the Loconet is connected - you either have a bad cable, or there is feedback through the Loconet somehow. CHeck you gaps to make sure no gaps have closed up between PM42 zones. Make sure there are no crossed feeders. Really wierd problems can happen when you have ONE feeder from ZOne 4's bus connected to Zone 5's rail.

 Do all the boards have their board IDs set? And NONE of them should be on the default. And check your address range witht he DS64s so you are sure you have no overlap - one of the other things you cna do with PM42s is send Loconet commands to them to make them turn off a section (as well as feedback messages that will tell you a section has tripped). Do you have anything else inthe mix, like a computer interface and a computer with JMRI? If you were messing around with panels and Logix you might have a panel with rules that are actually telling the PM42s to shut off certain sections when a section trips.

 Again - break everything down and add back parts one at a time until you see the problem come up - the last thing connected is the source of the problem, either the device or the cable connecting it.

                     --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

  • Member since
    September 2013
  • 14 posts
Posted by BrendanM on Thursday, January 8, 2015 10:48 PM

Thanks for replying.

The Loconet error comes from a throttle being left connected when the system turns on. It gives the command station 9 beeps. I've went through a while ago adding things one at a time and power cycling and I found the throttles are causing the problem (tested and re-tested) and they were the last things connected.

The throttles will cause the same error when plugged directly into either the booster or main command. I have noticed that the Ut utility throttles do not create this error, while anything newer (DT400(R)(D)) will. And yes, there are aux power supplies going to each of the UP5's through the coax. Trying to daisy chain them was a complete wast of time; it made no noticable differance in power avalible at the UP5's. And all cables are all made using RJ12 cables and connectors. I test them all (and almost every time I disconnect them) with the LT1. 

I have also added new ends (multiple times) to the throttles with no effect.

 

Onto the PM42's- I've checked all the gaps, feeder wires, etc. This layout was fully re-wired mostly by me and more than once I did have things crossed. I've learned to check-re-check-and check 20 more times cause there is always something missed. Months later everything is properly connected.

I have tested the boards without any of the track busses connected (just shorted out the track + - connections on the breakout board). So the problem is within the boards/loconet/grounding wires... not with the track busses/wiring. There is defenatly some sort of feedback through loconet AND the ground. If both are disconnected, everything functions as it should.

The ID's are all seperate from the DS64's (100's range). The PM42's are all 200's range id 200-205. The only settings I've changed on the PM42's are trip detection speed and trip current. And I've only changed these settings with Loconet Checker. Everything else I think is at defalt settings but I'll recheck. 

The computer is only connected for JMRI decoder programming and occasional locochecker changes--mostly for ds64 addressing-pm42 programming thrown in when needed.

Is it possible that there is some sort of logic programmed into the PM42's? That will control itself without a computer? Because I know Digitrax uses both loconet and the ground for comunications and maybe....?

This- How!-one of the other things you can do with PM42s is send Loconet commands to them to make them turn off a section (as well as feedback messages that will tell you a section has tripped).

Thanks again for any help!

  • Member since
    January 2001
  • From: US
  • 1,774 posts
Posted by cmrproducts on Friday, January 9, 2015 6:56 AM

BrendanM

Thanks for replying.

The Loconet error comes from a throttle being left connected when the system turns on. It gives the command station 9 beeps. I've went through a while ago adding things one at a time and power cycling and I found the throttles are causing the problem (tested and re-tested) and they were the last things connected.

The throttles will cause the same error when plugged directly into either the booster or main command. I have noticed that the Ut utility throttles do not create this error, while anything newer (DT400(R)(D)) will. And yes, there are aux power supplies going to each of the UP5's through the coax. Trying to daisy chain them was a complete wast of time; it made no noticable differance in power avalible at the UP5's. And all cables are all made using RJ12 cables and connectors. I test them all (and almost every time I disconnect them) with the LT1. 

I have also added new ends (multiple times) to the throttles with no effect.

<snip> 

Thanks again for any help!

BrendanM

Why the DT series Throttles cause the "9 BEEPS" upon startup is the DT series throttles draw too much from the Loconet when the system begins its "initialization" and the Command Station is not up completely.

This start up procedure takes about 10 to 15 seconds to stablize the DCC signals and the Loconet signals.

So this is always going to happen.

I never leave any DT series Throttle plugged in as all of mine are Radio units.

So I never hear the 9 Beeps.

There is nothing bad about the system when it send out the 9 Beeps as once the layout is stabilized you should be ready to go.

If the 9 Beeps bothers you then just unplug the DT throttles from the Loconet and just wait for 30 seconds after you start the system and then plug in.

BOB H - Clarion, PA

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