Digitrax is now shipping the UP6Z LocoNet 6 Jack Universal Panel with Voltage Reduction for Z Scale Layouts. UP6Z is a LocoNet universal panel/junction box with 6 jacks that works in all scales and can be set to reduce track voltage as needed for Z scale operation. What is it, what does it do, do we need it, will it keep me from burning up my decoders in the Marklin mikados??
Bingo! While there are many opinions that the DCC voltage really don't affect the motors in our locomotives as all, and it's true I have not heard of anyone actually burning out a motor due to the voltage of the DCC system, I have made this observation... Marklin Motors tend to get hot after about 2 hours of running on DCC, where both types of each AZL and MTL motors do not seem to exhibit this effect. I have no explanation for this observation, however it seems that lowering the voltage a couple volts and Marklin motors do not get AS hot as they were before. I have my DCC voltage turned all the way down to 9V at the track (NCE Powerhouse System) just to be safe. Maybe it's voodoo, maybe not. That said, after reading the instruction sheet of the Digitrax UP6Z, it seems Digitrax is also concerned about the track voltage level for Z Scale, especially since Digitrax does not have a track voltage pot on their boosters, so they offer this device to reduce track voltage. It will work with ANY DCC SYSTEM to lower the track voltage either 4 or 6 volts from whatever DCC track voltage is input, however it is unclear if you can use the 6 jacks for anything other than the loconet interface. If you are planning on running Marklin locomotives with DCC, I personally would feel it safer to lower the track voltage to 8-9V, so my Marklin locos do not run too hot. I have had a bad experience running a Marklin loco too hot, the motor heat caused expansion and split the clear plastic wiper cradle in one of my Marklin 0-6-0 switchers. This was not from DCC, but just running too fast for a couple hours, on a brand new loco. I would like to congratulate Digitrax for stepping up as the first North American DCC supplier to support Z Scale in such a big way. PS: it probably will not prevent you from burning up decoders in your Marklin Mikado. I identified one of my Mikado's which has had 6 decoders burn in it. It usually happens when I change direction from forward to reverse and back after the loco has warmed up. I suspect the wobble of the motor brushes allowing an in effect "short circuit condition" where the motor's resistance drops from normal 10 ohms down to 0 ohms long enough to kill the H Bridge in the decoder. No fix was found, so that loco can only be ran on DC going forward.
My experience with digitrax started in N and and I saw lots of problems in the early days, so, as a result when I saw the NCE power cab at NMRA shoe in Anaheim in 2008 I went to NCE for my Z and Nn3 as out of the box the power cab is 12v ac to the track and I am now using TCS decoders, in both N Nn3 and Z with a couple of CT electrnik added to the mix and I set motor volts start, Mid and top to limit power to the DC motor and since I have done that I have not had a decoder burnout or a motor burnout, Touch wood and after my experience with Z I went back and reprogrammed my N-scale to limit power to the DC motor using TCS and CT electronik decoders, I get no heat with long hours of running anymore and I have slowed acceleration and deceleration as well. With TCS decoders 255 = track voltage so 9v is about 2/3rds of 15 so I use 255 x .67 to get 171 which I round to 180 for top volts and mid volts I use 90 and for start I use 4, 3 or 5 depending on loco and how it starts. Sure this does not set the DC volts to the motor but it does control the power the motor is getting from the DCC decoder. DCC is what I use at home, but at shows I used DC and that is why I like the TCS decoders as they don't draw allot of power to get started in DC mode, ditch lights still work and I do not have to be quite as vigilant for wandering small hands when running on DC, and have not burned a decoder or motor or melted a truck side frame doing this for N Nn3 or Z at shows. My experience with digitrax in N was it was not friendly in dual mode DCC and DC. This may well not be what works for others but it certainly has saved me gnashing teeth and angst running DCC equipped locos, over the last 5 years.
I'm not running any DC locos on DCC. I would think the decoder would "insulate" the motor from any high voltage issue, no? (as long as it was within the spec of the decoder)
Motors are current devices so voltage does not matter as long as you limit your current. The decoders pulse the voltage to the motor to control the current. You can go full power and run the motor really fast to burn it out at higher voltages or if you have BEMF enabled and if there is some problem with the loco that stalls or overloads the motor you could over drive it with higher voltage and overheat it. The main reason for the scale (voltage) switch on the boosters is for the accessories connected to the track which could let the smoke out if they are sensitive to higher voltages. To make it fool proof the motors and voltage are being designed and set so the motor could be stalled at full power for a long time without burning up anything. It boils down to your application on how you want to run your loco, if you are running at shows and a large layout it would be a good idea to keep the track voltage low, and if you are running the loco by yourself and are going to keep an eye on on it at all times then the voltage is less of a concern. Kim
Doug, The answer is probably not, unless you want the extra LocoNet ports the unit provides. While I'm not familiar with your Digitrax unit, the documentation I have from them states that the track voltage is 12.8V and the "modern" AZL locos you want to run, while not outright specified, are all 12V motors. No problem I understand for those other scales, there are power boosters that can output 14 or 16 volts. These would be a problem. Likewise older locos from Marklin or MTL or AZL might have a problem on a 12V track. Mark
You can use the Zypher as it is. The 12.8v is *well* with acceptable. NCE's PowerCab puts out 13+ volts and hundreds of them are running our Z scale locos. As Kim points out, current is your enemy. If you stall a loco, that current goes UP ! That translates to Power, as in Watts. So think about a 2-3 Amp system at 12 Volts (keep the math easy) and you have 24-36 Watts. You know what that wattage of light bulb or a soldering iron feels like. So, if you don't stall your train (mostly in turnouts), we don't have problems. Always watch your trains ! Now, back to our program. DCC is great ! Multiple locos, directions, speeds, lights, sounds, . . .
That's why always preach short protection over reducing voltage. If you are going to run dcc, get a short protection.
