I ask this question because I have kicked around the possibility of upgrading my DC Transformer from a 15 volt dc output up to a transformer that outputs 23 volts.
What is the advantage of increased voltage DC? Will it make my locomotives run faster or will it have no affect? Curious and for those that would read this question and only respond by suggesting I upgrade to DCC let me stop you right now and say, I know I have thought about it but the timing just isn’t right.
Thanks
Will
Don’t do this unless you are running O Scale DC.
Most HO can motors are rated to run at 12Volts DC. N scale runs even less! Any more and you risk burning them out. If you buy a model with sound onboard, they typically engage a safety shutoff around 17-18 volts. Overvolting them will void your warranty.
If you need your engines to run faster, put in different final gearing . Try www.nwsl.com for replacement gear towers.
To be honest though, I wouldn’t even do this. Most people run their trains way too fast. And changing the gearing will make your slow speed movement less smooth/reliable.
If you want burnt out motors and light bulbs, go ahead. It’s like running your 3 battery torch with 4 batteries . You will get a very bright light for a very short time. Same with running your trains on higher voltages than they were designed for. Stick with 12 to 15volts.
If you’re having problems getting trains to run at full speed, check that the transformer has enough current (amps) for the load you’re putting on it, that is much better than raising the voltage.
cheers
Alan J
Ok sounds good, I had a sneaking suspicion that running a higher voltage may potentally harm my locos. Thanks for the reply
Will, what are you trying to accomplish, make the engines run faster, or run more engines?
On my Digitrax DCC system I have 3 voltage settings, one for N 10-12 volts, HO 12-14 volts O/G scale that I think will go to 20 volts. The Digitrax manual recommend running HO scale on the N scale settings. (thank to reduces claims on there decoders) I ran on N scale for a while and found I could run 10 engines, but they where slower and I need to clean the track more. Using the HO setting now, could still run the same number of engines but they could run faster and do not have to clean the track as much.
Hope this helps, and stay DC! Reason you ask? I got some free decoders from the DC folks here![:D]
Cuda Ken, looking for more DC friends again!
Will:
One DC power pack from Model Rectifier Corporation–their ControlMaster 20 has a dual-mode DC setting–12 volts for N or HO and 16 for G scale done by the flip of a switch. I have it on my layout and it does yeoman service. I run HO, but one time I accidentally flipped the switch to the G setting–only for a few moments until I realized the mistake–and yes, my locomotives had quite a bit of a faster response. But unless you want to end up eventually replacing all of your motors, I wouldn’t recommend running at the higher consistent voltage.
What I WOULD recommend for better starting and slow-speed control is the “Nudge” switch on the pack. It throws in a little extra voltage right at the beginning (not enough to damage the motor) and cuts off when the loco attains the speed you’re aiming for. It’s also very good for controlling most dual-mode DC/DCC steamers that take extra voltage to run with sound.
So, if you want smoother response from your DC locos, I’d definitely look for a power-pack with the 'Nudge" switch. I believe that it’s on several of the MRC models. The ControlMaster 20 is the model with the tether and hand-held controller so you can follow your train around the layout.
Tom [:)]
You are forgetting the MRC 6200–which also has two modes.
It all depends on whose motive power or lighted passenger cars you are running. For those who do choose to run MTH’s DCS system, it supplies a constant 12 volts to the MTH engines all the time–even when not moving. However, to run the very same MTH engines in plain DC mode one might need 16 volts to run the passenger steamers at a scale 80 miles per hour.
Some equipment would simply run a little faster if given 16 volts.
Some other manufacturers’ engines really don’t move all that fast at 12 volts, and I’ve found that they do run better perhaps at 13 volts or 14 volts–it depends if they have sound or not, too. Some sound equipped engines don’t do anything till 8 volts, and might have full speed (in plain DC mode) around 14 volts.
Various folks have also told me through the years that low speed creeping in DC mode can actually be harder on the motors than running at higher speeds (and voltages) because the motors run cooler at the higher speeds than in low speed drag service–and last longer than those in drag service.
I have a modest layout with an 81-foot mainline and no toggle switches or blocks anywhere (power routing turnouts instead). I have absolutely no use for DCC, but I did find that switching to the MRC 6200 does provide more “oomph” for those slow moving, voltage- or power-sucking, sound-equipped diesels and steamers.
Even the non-sound Bachmann Spectrum K-4 pulls a pretty good sized train quite nicely on 13 volts.
It’s your railroad. Run what makes you happy.
John
Voltage that high won’t help your locos at all if their N or HO, rather it could burn up the motors and a bevy of light bulbs to say nothing of any voltage sensitive LED’s that were installed.
I wholeheartedly disagree–I’m running HO and I have no problems.
The MRC 6200 also comes with a built-in ammeter and voltmeter–both of which are highly recommended even for Athearn Genesis diesels, BLI diesels, etc.
The built-in gauges do help me to assure my engines run fine.
BLI’s own instructions specify some sound equipped engines (ie the RSD-15’s) can run on voltages up to 18 volts. I think at 18 volts they automatically shut down to prevent damage.
With lesser quality power packs I experienced sound unit cutout, and power shut down on some Athearn Genesis diesels because the voltage got too high (and I didn’t know what it was). Switching to a power supply like the MRC 6200 is highly recommended for those folks who choose to run sound equipped units from multiple manufacturers.
The different manufacturers have different voltage ratings on their engines. Some HO engines can even take up to 22 volts and be just fine. One must read the instructions–especially with sound equipped units.
John
MRC 6200
Mode I: 0 to 18.5 volts DC
Mode II: 0 to 14 volts DC
Some, not all. My nephew burned out three locos at 20-22 volts. A Bachmann 0-6-0, a Model Power F unit and an older Athearn GP9.
John, unless they changed the MRC 6200, you must have a MRC 9000 or a 9500. Here is a link to the 6200.
http://www.modelrec.com/search/product-view.asp?ID=1262
I had both the 6200 and 9500, 9500 had the gages. 6200 was a POS, and went back to my LHS, had to beat on it to get it to work.
9500 on the other hand was sweet! Here is a link.
http://www.modelrec.com/search/product-view.asp?ID=1265
If I had stayed DC, I would have bought 3 more.
Cuda Ken
John:
You bring up a good point, and also a question from me.
I am given to understand that dual/mode DC/DCC locomotives DO require a higher voltage to run well in straight DC because of the advanced electronics to operate the sound. In fact, I understand that MTH locomotives work best at about 20 volts DC, and BLI locos only a little bit lower (the several I have require at least 8 volts to even get their sound working and lights on just standing still).
But In my case, I run mostly brass locos (because of the railroad that I model) with DC can motors and the motor-gearbox designs are designed to work more efficiently at the lower speed ranges. I very seldom run my locos at more than 45-50 SMPH, and the motors have all proven to have a very long life on 12 volts maximum. The 'Nudge" switch on my power pack evidently temporarily throws about 14 volts max for starting, then cuts back to 12 volts after the loco has obtained the speed that I want to control it.
What I’m wondering, is by using the Mode I of 16 volts instead of the Mode II of 12 volts, am I going to be eventually damaging the can motors of a brass locomotive that isn’t dual mode? That’s my main concern.
I’m talking ‘pure’ DC here, no “bells and whistles.” My BLI’s are in boxes, packed up and ready to be sold because of incompatibility with my basic DC roster.
Tom
Virtually all control/motion decoders made now are “dual mode” so an engine with one installed (at the factory or by the modeller) will work normally under either DC or DCC without the modeller needing to do anything. They should run at the same speed (or near enough) regardless of whether in DC or DCC, unless you adjust the CV’s so it runs slower in DCC.
However when you have a dual-mode sound decoder, the circuitry basically applies the power to the sound system first, and once that has enough power to make noise correctly, begins applying power to the motor. That’s why a sound equipped engine has trouble running with a non-sound one on DC, since the first 6-8 volts or so of power go to the sound system, so the non-sound engine is running along at track speed before the sound equipped engine has even started moving.
AFAIK there should be no problem using a powerpack with more power to run a sound-equipped engine. I wouldn’t go nuts and start running 20+ volts, but a little extra power above 12V DC should be fine.
When in doubt, send the manufacturer an e-mail or check out their website, I’m sure you wouldn’t be the first person to ask this question.
Some confusion here about voltage and current, and which affects what.
If the load is the same, when more volts are applied to a DC motor, the RPMs go up. Usually in the range we are discussing the load does not vary significantly from 12V to 16V, so the extra voltage makes the locomotive go faster. Depending on motor design, there are diminishing returns to extra voltage for extra speed. Smoothness of the commutator and brush design determine what the maximum RPM is before the brushes start losing contact, providing some self-governing of the motor. And balance of the rotating motor parts and the bearings will impact how fast the motor can turn before it vibrates itself to pieces. But none of this is overheating or “burning up”.
The current (amps) going through a motor are proportional to the load on the motor. And the heat produced in a motor is proportional to the square of the current. Adding more cars drives up the motor current, as does going up a grade. All DC motors have a maximum continuous current rating that should not be exceeded for the longevity of the motor. This max continuous current rating is almost always less than the stall current of the motor. So stalling a motor with an overload is a leading cause of burnt up motors. In the bad old days, locomotives would be weighted so that they slipped their driving wheels before they reached their max continuous current. This provided a safety margin in normal operations - the drivers would slip before the motor would overheat in most circumstances. Traction tires remove the safety of slipping drivers.
Extra or too much friction in the mechanism is the hidden killer of motors. Due to poor assembly or QC of the locomotive, high friction can make the motor current a lot higher than it should be right out of the box. Slipping drivers is only a safety valve for ad
Thanks fwright for the good explanation.
Forgive me for being confused–I now currently only use the DC power supply to provide power to the DCS Controller. I also use the DCS controller to run trains in plain DC mode because with the wheel, the DCS controller offers more precise speed steps–and also constant voltage readout in plain DC mode versus smph in DCS mode.
I had the 9500 but must have sold it when I dumped some other manufacturers’ locos last year and switched to a mostly MTH roster. I think the 6200 actually puts out more voltage–so I needed that.
One thing I noticed was that many engines, running flat out full speed, never reach the “maximum” rated voltage of the power supply–so if you have a power supply capable of higher voltages, but you run your engines at moderate or “prototypical” speeds, you have nothing to worry about. Just because a power supply is capable of putting out as much as 18 volts does not mean your engine will actually receive that voltage. I tried with Athearn SD40’s running flat out, and couldn’t get them to 16 volts–and I normally wouldn’t run them that fast. At 14 volts, they were moving plenty fast enough for my layout.
If you run MTH steamers in plain DC mode, you will need about 16 volts to get them moving at a scale 80 mph. This is because you are feeding the lights, sound and smoke unit. The very same engine running in DCS mode only receives 12 volts (and runs better).
Disclaimer: I’m not implying that everyone should use DCS, or that everyone should buy the MRC black box to run their sound equipped engines. My statements reflect what I use only and are not an attempt to get you to switch from what you like.
I would not run over 12-Volts for HO. I had a problem with boards burning up on Kato units several years ago and it was only after several heated (no pun intended) conversations that I found out about their lower allowable voltage ratings