Hello! I own a bunch of DZ123 and have some problems getting the locos started by CV2. Many, not all locos create a jerk (jump) first before they start slightly moving. I use the 3-point-speed setting by CV2,6 and 5. Since this decoder is almost a grandfather is was designed for older locos, creating a kick first to get the motor in motion. This is not required for modern 5-polers. How is this to cure? Have some of you the same experience with this decoders? Is his succsessor better (ok, it has BEMF and is smaler in size). Probably Digitrax was not able to handle the 3-step-speed table at thoses they developed this one. Would it be helpfull to use the 28-speed-curve although I can switch off the kick start by CV65? Regards Mathi
Sorry, cant help with your actual question, because I have never had any issues. I have several locos with the DZ123 in them and have never had any issues. All of them with the 5 pole motor. I also have many with its predicessor the DZ125 again with no problems.
Hi Louis, thanks for this suggestion but if I do this I need more speed steps on my throttle to get the engine run. Wasn't the idea of CV2 to set the very slowest but consisting starting point at throttle 1? Ok, this could solve the problem depending on the loco. If a loco needs few power to start consist it will work. The other one needs a higher power level and the throttle is to set on step 3 or more to start the engine. I'll give it a shot tonight, thank you! Regards Mathi
Hi there! Well, it works as I said! Engines with low power to start and less friction start moving on throttle steps 1 to 3. This is tolerable, but some other locos need up to 6 steps before they show movement. These are in need of speed table tuning, some work for a rainy day! Another story about DZ123: I had on of these in a Bachmann H16-44 (nice loco and ran very well with it). It even works well on DC, CV29 is 6. Last day I put it on a friends dc-layout and it cruised for about 20 min., then it sudden stops, a loud "Pop" was audible and "electric smell" was in the air. This was the end of the song! I opened it and the first thing I saw was a fried decoder. The DZ123 burned 3 or 4 black spots through the red insulation, both LED are on, flickering. I took it out and put back the two brass clips to check if it runs on DC yet. Yeah, is was ok so far, but the LED's are off on both sides. I checked the pc board for burn marks (nothing visible for my old eyes) and metered the LED's on board, both are alright. So what is going on? Next to do is to solder an other brands cheap decoder in it to see if it works as before, but more and more I'm done with those DZ123. Some my question again. How is your experience with the newer DZ125, is it better? Thank you Tudor for your reply but I wonder why I have this issues (different locos and brands, all new and broken in, some have doubles with other decoders and work fine). Probably is it caused to the digital system I'm using. It is very common here in Germany and its for HO as well but has no device to turn down the power for N scale? Once I used a power supply with less output this effect improved and was almost gone. The drawback was I needed to adjust all my CV's again. The locos behavior changed due to less power. Enough so far Thanks for reading this! Mathi
Hey Rich! My digital system ist the TRIX MOBILE STATION, very common here in Germany over many years, developed by Märklin / Trix for SX and DCC. It has a standard power supply with 1,9A and 24V for the needs of HO. I guess this is to much for N and are planning to reduce the power by an array of rectifiers (as suggested on the Atlas hp). The DC-layout, where the decoder gave up his gost, is powerded with an older but well working transformator+throttle in one with a turn knob for left and right movement (means comutate) and delivers 0 to 12 DC for track and 16V AC for switches and/or lighting. This device has been used extensively over 10 years and never caused any problems, not even with DCC locos on DC layouts. Well, I'm unhappy, sort of.......! Regards Mathi
Using 24 volts for your N scale layout is way too high , I think you should invest in a better power pack to save your units ! On my Digitrax system there is a switch to power HO or N . I have installed a lot of the DZ125 and they are very reliable . I also have programmed mid speed , top speed and momentum on the start and braking . All my units are now smooth as silk . All my units have now the same top and mid speed . It's a lot of fun to be able to run any type of locs together . I just begun to play with CV2 with a few LL E8 units and it improoved their operation a lot , these units were a bit slow to "understand" to start moving . I use Decoder Pro to program my locos and it's a lot easier to change CV value , this program is available for free . Just do a Google search to find it . You will also have to buy some hardware to connect the computer to your DCC system . First of all you should get a real "N" DCC system to save your units !
Hi Mathi, I Have been using the DZ123 decoder for years and I just installed 3 in the past couple weeks and have 7 more on order. I have not had any problems with them. As to way the one gave up the ghost while running on DC at 0 -12 volts, my only guess is that maybe because it was run on the much higher 24 volt system the decoder was damaged. I have a inline volt/amp meter that is designed for DCC. The voltage reads 11.5 and my Digitrax system is set for N Scale. Digitrax states on their website that the DZ123 Works with most DCC-ready Z, N, and HO scale locomotives up to 18V track voltage. 24 volts is 133.33% the maximum recommended voltage. Gary
Hi Gary, thanks for your words. The longer I was thinking about it I came to the conclusion to lower the volts on my DCC system, not the amps. So I put two bridge rectifiers, each in the two cords from central to track They are in line with the two ac outputs while the + and - are joined. This lowers the track power 2 - 2,5 volts. I've to check this for a while but the first thing I observed was the decoders are less warm than before. That indicates the genuine system uses too much volts. The DC track voltage was common 12V, reason for toast must have been caused different. Anyway, I'm looking forward with these rectifiers! Regards Mathi
You really shouldn't be running these decoders on more than about 15V DCC track power (12V track power is recommended for N Scale due to the motor ratings). Most likely the bridge rectifier in the decoder has been stressed by the excessive voltage and failed. On your DC power supply, are you using capacitors to filter the DC voltage? What type of rectifier are you using? Rich
Supply voltage and DCC decoders As others have mentioned 15VDC should be about the maximum for supply voltage. Many of the better DC power supplies (throttles) had a switch to limit the output voltage to 12-14VDC for N and Z scales, to avoid motor overheating. The over-voltage and heating is just as much an issue when using DCC. If you are trying to reduce from 24VDC to 15VDC or even 18VDC, that is going to require a lot of series rectifiers to get the voltage drop you desire. A better method would be to install a voltage regulator chip rated for the power requirements you need. There are a number of circuit designs for voltage regulators available on model railroad electronics sites - just do a Google search. Reducing the supply voltage to what you need should make ALL your electronics happier!:tb-biggrin: Best regards, Don
Hi friends! Lets get back to my DZ123 problem with bump before slowly speeds up. I solved this after messing around with CV settings. I set CV65, the kick start to 0. The DZ123 has a factory value presetted at 1 (along with a complete speed table default). I have no CV29 setting for 28/128 speed table and despite the Digitrax manual does CV65 work without setting for those speed tables. Now I can adjust, as I know it from any other decoder, the start speed on CV2 with no more bumps or jerks. The locos start smoothly now. There is just a mistake in the decoders manual, thats all! Now theyare fine with only the CV2,6 and 5 plus 3 and 4 for acc./dec. Regards Mathi
