Hi all,
I just got a digitrax DCC system and it has a feature where you can run a DC locomotive on it alongside DCC locos. The person who I got the system from does it with his DC locos, but I’ve read both from manufacturers and modelers that it’s potentially bad for the loco. What’s your experience with DC on Digitrax?
Yes, and no.
It can cause the motor to heat up, and if left standing it will also heat up. It was designed for Direct Current and it won’t like the DCC waveform. The nature of the DCC waveform creates a lot of heat within a motor.
If it has a coreless motor, it will be destroyed quickly. Not an issue for older locomotives, but if the motor was replaced the new one may be coreless.
Occasionally running an old DC locomotive isn’t really an issue, just don’t leave it on the track or move it to a section which can be isolated and disconnected from the DCC system when you are not using it.
If you purchase a new DC locomotive, read the instructions as it may warn you about using it on DCC.
The ability to run a DC locomotive on Address 00 was a feature added in the early days to keep some modellers happy. If it disappeared tomorrow no one would really notice. In the early days of DCC some manufacturers felt that it was necessary to include Analog capabilities to sell their product to a hesitant consumer. Many modellers had a very dim view of command control in the 1990s.
If you just run it and then remove it you should be ok. The problem arises when you forget and leave the DC locomotive parked on powered track. If you run mainly DCC you get used to the stopped locomotives taking care of the continuous power supply issue automatically.
https://www.digitrax.com/tsd/KB774/dt400-how-to-run-an-analog-loco-on-address-00/
So, for a demonstration run just to enjoy running the one DC locomotive and nothing else on the layout, sure. But don’t forget and leave it on track after you’re done. You will forget and you will then destroy the motor.
A much better idea is to just slip a decoder into your DC locomotive(s). In many cases this is not too difficult.
If the DC locomotive is DCC ready then it is really easy. You can usually save the jumper plug to convert back if you ever needed to.
I have a MRC Tech 6 in order to run a fleet of DC and DCC locomotives on the same layout while I go through this decoder installation process one by one.
Even with the Tech 6 you must remove all DC locomotives from powered track before pressing the all too convenient DCC “dual mode” button. Just BTW, the label on that button ties with Tesla’s “auto pilot” button for most misleading label ever. It is in no way shape or form a “dual mode”. It should be labelled: DCC ONLY!!! (The Tesla button should just be deleted until they fix their" self driving" software.)
So, since I am having trouble with my DCC engines pulling my CMX track cleaner, I can hit 00 and run my old Kato’s NW2, have a pair that I know will pull it ?
The two points where the brushes contact the armature get quite hot when the loco is sitting still and DCC still on the rails. The amature is still vibrating at the DCC frequency. I did measurements some years ago with an infrared temp scanner. I could see those two points even through a can motor shell on a test stand.
Rich
Just get a single DPDT switch. Hook one side up to a good dc power supply. Center will be OFF, and hook other side to DCC system of choice. This WILL STOP the dcc system from seeing the dc system as a short and WILL protect the dc diesels.
I have several units each of the very same manufacturer’s current diesel models in both dc and dcc. The power loss due to ESU LokSound Version 5 decoder combined with the manufacturer’s crappy garbage mother board is quite noticeable in engine performance on the layout. It is enough to sometimes kill a motor that works adequately in plain dc. (I have one dcc unit dead so far).
Honestly, I do not like dcc. It is difficult to run an advanced consist and then play with sound or lighting effects on individual units at the same time without stopping your train from moving when you return to the consist. I think dcc just utterly sucks. Also this is because I can NOW readily see the actual loss of performance of the dcc loco due to all the boards sucking voltage, power, and current. They run MUCH better in plain dc!
I fail to see how dcc is a “gain” unless you love the lighting functions (and sound).
John
John,
A consist in DCC is usually set up so that you control the sound and lighting effects of the lead unit. While you can set up and adjust those on the individual helper units, you should do this before setting up your consist. And the lighting effects are really only going to pertain to the lead unit, yes? Once the consist is broken apart, the individual locomotives retain their individual lighting effects.
I don’t run many MUs but I’ve not had issues setting them up, operating, or breaking them apart using with my Power Cab. It does not support “00” addressing though, which I’m perfectly fine with.
Tom
I have a Lenz DCC system which also supports the Engine Zero option for DC engines. I’ve tried a few and the horrid performance and buzzing noise immediately sent me out to my LHS for a decoder.
As a side note, be aware that an autoreverser for DCC will not work with a DC engine used this way. The autoreverser works fine, but the DC engine will reverse when the phase is flipped, while a DCC engine will keep going the same direction.
I have to agree one of the main advantages of DCC is running the trains together, the other is sound. I don’t ussually need to run engines together so the sound is what won me over. Yes you can have sound in DC but it is way harder.
It ‘works’ but to varying degrees, depending on the loco. The main intent was for N scale locos in the early days of DCC, when decoders were a lot bigger than the ones we can get today and before all the N scale locos had easily swappable boards with multiple manufacturers making decoders for them. Athearn BB locos for example, buzz horrible - those gold motors are loosely assmebled so the whole thing vibrates. Some better wuality motors run better, but they will all buzz or sing to some degree - the DCC frequency is within human hearing range, especially the younger you are.
As mentioned - don;t leave a DC loco sitting there not moving. In this situation, many times it’s the better quality motor that is more vulnerable to overheating.
Sometimes it comes in handy - once had an old Bowser PRR T1 that had been built up but never run, just packed away for 15 years. Put it on the DC track, and it wouldn;t turn, just popped the overload on the DC power pack. Put it on the DCC track and tried address 00, and it gradually started turning. The more it ran back and forth, the better it got. I wasn;t too worried about the open frame motor overheating, there was plenty of airflow, especially witht he armature turning, even slowly. It wasn’t particularly noisy, but a real 2.5 amps from the DCC system combined with the harsh pulses got the motor and gears moving and worked everything loose to where it was finally able to run.
–Randy
I’m pretty sure 00 addressing won’t work for more than one DC locomotive at a time.
All the current dual mode decoder DCC locomotives automatically produce sound when running in DC mode.
The only drawback to operating a DCC locomotive in DC mode is the narrower range of throttle control due to the minimum startup voltage of the sound decoder.
Unless you already own the DC powerpack buying the MRC Tech 6 is an easier solution. If you also get the handheld extension throttle that’s enough to control up to six DCC locomotives concurrently on your layout.
You may need an auxiliary power source for most accessories though since the Tech 6 only outputs track voltage.
Fitting the DPDT switch also does not eliminate the “forget factor”. You can still inadvertently deliver DCC line voltage to DC locomotives left on track. The switch system only protects if you remember which type of locomotive might still be on powered track.
What’s actually needed is a power system that automatically defaults to DC every time you switch it off and switch it on again. Even that’s not foolproof but the operator will realize it’s set to DC as soon as it takes 3/4 throttle to wake up any locomotive. Up to that point only the DC locomotives will move.
It would have been handy if the Tech 6 did that but it doesn’t. It restarts in the same mode as when you turned it off.
I actually had a Tech 6 until it wore out (knob went past zero and so it would not “stop” trains) and then I replaced it with a new MRC Tech 7, which works very well but does not provide the same features–is a conventional plain dc power supply–but a good one.
BUT
My son wanted some fully featured Athearn Genesis 2.0 SD90MAC-H’s and we also acquired some other dcc units. The other dcc units have not worked out well, so much so that dc replacements have been ordered and arrived. My dcc units are on Ebay currently.
Now, back more on topic: We don’t have all that many units on hand and I never ever leave locos on the track unless they are my son’s for him to run. So I know which units are plain dc and which ones are dcc. That is not a problem (actually because all dcc units excepting my son’s are up for sale).
With the DPDT switch ONLY the selected power supply is active. NO power from the other supply can get to the rails. Most problems are solved. Most people unless they are new to the hobby already have a decent dc power supply.
It is perhaps easier to program cv settings with the NCE Powercab than it is with the Tech 6, or at least you have ready access to more of the cv settings than one actually has with the Tech 6, as I think it is limited in which cv’s it can change.
John
The Lenz DCC System on address ‘‘00’’ will run at least two DC locos together or separately with each having a train in tow. All the DC Engines should be speed matched if running MU’ed. All DC Engines will run in the same direction on the track no matter which way they are facing.
You can leave ‘‘00’’ and the DC locos will still be moving at what ever speed and direction you left them on.
I think it was me that was corrected later down the line of replys. I edited my words above. 10/26/20 8:40 pm.[:$]
Now my cloudy mistaken and confused thoughts may have gone back to when, I would change the wire leads to the motor, then the DC Engine would run in the opposite direction it was intended to.
It also works with Digitrax. I sometimes use “00” to test DC brass engines, and there is no problem with running two at the same time.
Thanks for the advice everyone, I breifly tested a DC loco on it today but the terrible buzzing, poor control, and apparent risk of overheating and ruining the motor was enough to convince me to order a bulk pack of decoders.
Good choice Harrison. [Y]
Mike.
Address 00 will run as many DC locos as there is current capacity in the DCC system. They just aren’t individually controllable. It’s like having 4 DCC locos all set to the same address.
–Randy
But you’re not running them.
What do you mean “you’re not running them”? If I put 4 DC locos on the tracks, dial up address 0 on my Zephyr, and increase the throttle, they will all move. If they are the same brand, with the same motor, they might even move together, at the same speed, like they would on actual DC power. I have speed control and direction control. Unless one is wired backwards, they will all move the same direction. I could keep adding more locos, as long as I don’t exceed the 2.5 amps the system can supply. Or I could power the track through my DB150 booster and run up to 5 amps of DC locos simultaneously.
Exactly the same as using a regular DC power pack, or the same as having multiple DCC locos all set for the same address - select that shared address and all locos using that address will move at the same time. Same direction, same speed (if they are similar locos).
–Randy