Bit by the DZ-2500 Serial Data Bug

Our club tried these not long after they came out. 6 months later we replaced them with DZ1000s. That was a dozen years ago. I guess they still haven’t been sorted out.

Pete

Darn!@!   That sucks!   I blew the engine in my '85 MB 300TD on Saturday.  Oil cooler line blew and I didn't notice it as I was tooling along on I-10 ...one MB down four to go.  I have almost as many MB(s) as I do switch machines.

@gunrunnerjohn posted:

Disconnected all the serial data feeds, and power cycled, local control of the switches returned.  Started removing serial data leads from each switch until the DZ-2001 LED went out, I replaced that switch machine.  Reprogrammed the new switch machine and we were back in business.

John,

This is my biggest concern.  You stated you first Disconnected all the serial data feeds, then after re-powering them, you disconnected them again.  Did you re-connect them first before disconnecting them again (one at a time?)

I have a feeling I will be doing this too.

Thanks.

Well, since I was given a heads-up on the serial port issue, my serial feeds are in groups of six.  So, I can disconnect six at a time and narrow any issue down to those six leads.  When I pulled the lead that was lighting the DZ-2001 LED, all the other switches worked again.

I used the CSM2 Breakout Boards for my switches, so it was pretty easy to just pull the DZ-2500 wires from the breakout board press-in connector and install the new switch machine.

I think your engine was more expensive than my switch machine.

Pete, I looked at the DZ-1000, but I wanted the smaller footprint and of course, the command control.

Sure hope you get the bugs worked out on those things and they can be made so work reliably.  At least it sounds like you are in the home stretch anyway.

@gunrunnerjohn posted:

I used the CSM2 Breakout Boards for my switches....

John,

Thanks.

I was hoping the BBs would fix this.

I recently had the same problem with a newly relocated turnout. I bought a brand new turnout with the DZ2500 switch machine, wired it up to the lose of control on all the switch machines. Replaced it with a spare and now all the turnouts are functioning properly. Best advice I have for the new layout builder is less turnouts in easy to access locations. You’re gonna have to replace one sooner or later.

This confirms my decision to go with DZ-1000. I had read about DZ-2500 problems. I love technology and would use the DZ-2500, but I don't need this aggravation. It's enough that I have to replace Atlas switch machines. I was hoping that the DZ-2500 problem was outdated information.

Keith,

If you go with DZ-1000's will you be activating them by command control?  If so, how?  I'm thinking of ASC2 or  AIU perhaps for my situation.

Mike

I feel your pain John. I have over 30 of the ROSS / DZ2500 switches. I had the DZ1000 on my old layout and piggybacked the DZ1008 relay to most of them. They always worked flawlessly but were big and some equipment would hit them. I paid the premium for the 2500 on my new layout because they were much smaller than the 1000 and I did not need the relay plus I liked the remote interface.

I had so many problems using the remote interface, I went back to push button operation for the motors. Even doing that, sometimes they "stick" and do not work, even with a lot of tinkering. Some I removed the motor completely and just installed ground throws where convienent.

For me, in hindsight, I just should have bit the bullet and installed Tortoise motors under the layout. They are much more difficult to install for me, but once done, they will work forever.

Live and learn. Pre-covid I had a discussion with Dennis about this at the York TCA meet. He offered to replace any defective motors for free if I send him the bad one. I did get a few replacements but now just live with all the quirks. I am not a Sparky so once something does not work as advertised or as shown in the directions, I need to move to Plan "B".

Donald

I'm back in operation, and I have a couple of switch motors to send back to Dennis.   Given the fact that I think I followed all the guidelines for these, I'm not sure why they should continue to croak.  I am supplying them with 14VAC to limit heating from a separate supply for just the switch machines.  I feed all the serial data with the DZ-2001 Data Driver.

The one complication is the four turnouts on the second level have extended leads to get down under the main level, when I have to swap those out, it's a much larger PITA.

@CAPPilot posted:

I was hoping the BBs would fix this.

Those are really targeting the issue with the non-derailing inputs getting a spoke and killing the board I believe.  The serial data just goes directly back to your serial data driver.

@Oman posted:

This confirms my decision to go with DZ-1000. I had read about DZ-2500 problems. I love technology and would use the DZ-2500, but I don't need this aggravation. It's enough that I have to replace Atlas switch machines. I was hoping that the DZ-2500 problem was outdated information.

I read about the DZ-2500 issues as well, I just figured I was smarter than all those people.  Just shows you how wrong you can be!

@3rail posted:

For me, in hindsight, I just should have bit the bullet and installed Tortoise motors under the layout. They are much more difficult to install for me, but once done, they will work forever.

I did think about using Tortoise switch machines, but it's so much more work to install them, and I also would have to add all the wiring and controls for command operation, I decided to go with the DZ-2500.  I may yet regret that decision, but that's water over the dam at this point.

@Mellow Hudson Mike posted:

Keith,

If you go with DZ-1000's will you be activating them by command control?  If so, how?  I'm thinking of ASC2 or  AIU perhaps for my situation.

Mike

At this time, I don't have any plans for command control of my switches; just push button.

One thing for sure John. When you’re unable to sleep at night thinking of the problem you’ll come up with an electronic solution that will help many people with the same problem. We will be waiting for it to be sold thru Hennings Trains.

Well, the "solution" for the way I wired would be fairly simple.  Since I ran every switch back to my power/control panel, I could simply build a PCB with individual serial data buffers that would isolate each serial data line so they couldn't affect each other.

For people that daisy-chained the serial data, you could add a tiny little buffer at each switch and accomplish the same thing, but it would be a bit of wiring.

It all comes down to the frequency of failures.  I'm certainly hoping I don't have enough failures to have to resort to extreme measures to solve them!

John, thank you for keeping us informed as you work through this installation.  I didn't see the value of the break-out boards and in truth, they don't seem to have been much help.

I too, have encountered issues with DZ-2500 switch machines in past, in particular the DZ-2500A model.  Dennis Zander has always replaced the problem children promptly and for free.  Fortunately, the DZ-2500C is much more reliable (although not perfect) in this regard.  The solution, or at least the work-around, is limit the number of switches controlled by the white DZ-2001 data wire to small groups (4 or less).  The photos below show how I did it.  It's not a solution - it's a faster diagnostic approach that acknowledges the issue and helps resolve it quickly.

As to alternatives:

• By comparison, the Atlas switch machines (a simple solenoid) have a much higher mortality rate.
• The DZ-1000 has been reported as significantly more reliable, but does have the larger form factor and is not directly addressable via command control (ASC-2, DZ-2000).
• The Tortoise enjoys a wonderful reputation both here and in the HO world and with its under-the-table installation might be the best approach, but I have some questions for all of you:

1. Does the Tortoise require DC only power?
2. Does it have any external outputs or ways to control signals?  If so, whose?

Thanks,

George

I separated my switches into blocks of six for the serial data, and then those blocks are wired together at the power/control panel.  I'm thinking I'm going to add a terminal block to make it easier to disconnect these in the future.

@G3750 posted:

1. Does the Tortoise require DC only power?
2. Does it have any external outputs or ways to control signals?  If so, whose?

The Tortoise switch machine has two sets of SPDT contacts rated at 1 amp.  Given that fact, it should be adaptable to most signals.  The motor is a DC motor rated at 12VDC or less, and will not be harmed by continuous application of power.

Tortoise current draw is so low that you can put a red/green LED in series with them so you have visual indication of position. I have mine wired through DPDT LATCHING relays operated by a SC-2 controller. Needs + and - 12 volt power on the SC2s. Added benefit is when you turn the layout off and back on the switches stay the same as when it was turned off.

GRJ, I am interested in using the DZ2001 with my DZ2500 switch machines.  Good idea or bad idea?  I have read this entire post but want your opinion. If I do this I would take your advice put them in groups to make troubleshooting easier.

Another question is does the CSM2, instead of the DZ-2001, solve or at least help this issue?

@Tanner111 posted:

GRJ, I am interested in using the DZ2001 with my DZ2500 switch machines.  Good idea or bad idea?  I have read this entire post but want your opinion. If I do this I would take your advice put them in groups to make troubleshooting easier.

The DZ-2001 works fine with the DZ-2500 switch machines, that's what I'm currently using for mine.

@CAPPilot posted:

Another question is does the CSM2, instead of the DZ-2001, solve or at least help this issue?

Actually, the CSM2 doesn't work properly with the DZ-2500, that's why I stopped using it and went with the DZ-2001!

I believe I've figured out what the issue is.  Apparently either the CSM2 initializing it's serial outputs or the DZ-2500 seeing something it doesn't recognize on the serial data causes the issue.  What happened to me is about every three or four times I'd power up the layout, all the DZ-2500 switch machines would be locked up solid!  They didn't respond to local or serial data control.  The best guess is that they were in manual control mode where you use them like a manual switch machine.  I suspect that by simply delaying the power up of the DZ-2500's for a couple of seconds after the CSM2 boxes were powered up would solve it, but I haven't gotten around to changing things to do that.  Since the DZ-2001 is working fine, I didn't see the urgency to change back to the CSM2 serial feeds.

@Tanner111 posted:

GRJ, I am interested in using the DZ2001 with my DZ2500 switch machines.  Good idea or bad idea?  I have read this entire post but want your opinion. If I do this I would take your advice put them in groups to make troubleshooting easier.

The DZ-2001 was designed to run multiple DZ-2500 switch machines, so yeah it's a good idea.  I've been using this set up since 2006; works great with the noted caveats.  And if you look at my previous post, I've given you a simple way to group them for debugging purposes.

George

I sold all 30 of mine and installed tortoise machines because all that had to happen was one 2500 to not throw all the way and the rest stopped. never had a min trouble with the tortoise .

Having some issues with a few DZ-2500Cs. Brought them over to DZ, he lives nearby. He reprogramed them.

I thought at the time that it would be nice if I could reprogram them.

If anyone is thinking of going back to DZ 1000’s you better have deep pockets. The large dealer of ZStuff at York now sells them at $34.95 each. I have 36 of them so I’m sitting on a goldmine. 😂😂

@AlanRail posted:

Having some issues with a few DZ-2500Cs. Brought them over to DZ, he lives nearby. He reprogramed them.

I thought at the time that it would be nice if I could reprogram them.

I have the tool to reprogram them, but I don't have the binary file to use.  The DZ-2500 uses the Microchip PIC processor, same family as I use in some of my boards.