Running two locos on DC at same time?

Started by GoCanes, February 15, 2012, 01:32:15 PM

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GoCanes

Is running two locos on the same DC track a risk to the engines or power pack?  (I mean on the same block at the same time)


jonathan

There is no electrical danger to either the locomotives or the power pack.

I do it all the time (double heading).  I suppose, if you are running two different trains, there is a risk of rear-ending a train, if one locomotive runs faster than the other.

Regards,

Jonathan

phillyreading

The only concern is would your powerpack be strong enuff to handle the two locomotives? Some smaller powerpacks may heat-up after a few minutes.
I had a GG-1 that needed a bigger powerpack, as it would barely crawl with the powerpack I used at first, I bought a two train powerpack and it worked fine.

Lee F.

Desertdweller

This should be no problem, as long as you have the amperage.  For HO, I would think 1 1/2 to 2 amps would be plenty.

Of course, your locomotives both need to be wired so they both move in the same direction when under power.
This used to be a problem once upon a time.

I would do this:  Put both locomotives on the track, facing however you intend to run them.  Don't couple them together, leave them a foot or so apart.  Turn your throttle so they move about the speed you want to run your train at.

What you want to do is determine if they both run about the same speed at the same throttle setting.  If they will both run awhile while keeping roughly the same distance apart, they will work together (DCC systems somehow can compensate for variations).  Couple them up and run both powered units as if they were a single locomotive.

Les

phillyreading

Les,

What you mention is how I test O gauge engines for compatibilty as well, except I leave just a few inches. If one tries to out run the other then I know it is not a match. Just because you have two of the same engines, they may not run at the same speed when on the track together.
I double head some SD-45's in O gauge.

Lee F.

electrical whiz kid

Probably the most reliable method is to use an ammeter or wattmeter to monitor the watts o/r amperes consumed.
A standard medium load HO engine should consume in the neighborhood of 1-2 amps.  Most good transformers have overload protection in the form of thermal overloads.  I know that MRC power packs generally do.  As was mentioned also earlier, if you are running two engines in unison, they will "mimmick" each other as the result of the electricval characteristics.  There are several forms of multi-trin operation.  Why not look into these and try one?
Rich

Doneldon

Quote from: electrical whiz kid on March 20, 2012, 10:10:23 PM
A standard medium load HO engine should consume in the neighborhood of 1-2 amps.

Rich-

This would only be true for locos with older motors and sound. Modern can motors
use much less current, often in the range of .25 - .40 amps, and less than an amp
even with sound.
                             -- D


Jim Banner

Quote from: electrical whiz kid on March 20, 2012, 10:10:23 PM
Probably the most reliable method is to use an ammeter or wattmeter to monitor the watts o/r amperes consumed.
Rich

How does this tell you if the two locomotives are fighting one another or are running at the same speed?

Jim
Growing older is mandatory but growing up is optional.

electrical whiz kid

JIM;
speed would obviously be a calibration of its own.  Depending upon gearing, and to some extent motor design (as was previously mentioned here), two motors on the track would be considered parallel loads, and as such, one would not  "control" the speed of the other.  A wattmeter would indicate the sum wattage consumed by both engines at the same time.  An ammeter would do likewise with ampacity.
DOn; I will be the first guy to tell you that I am not that familiar with the newer motors, but they would, to my knowledge, operate in the above manner.  I have some reading to do about the particuliarities of the newer mechanisms.
Rich

jward

using a watt meter to determine ;load sounds good in theory, but it doesn't account for differences in the motors and drive train.. even two "identical" locomotives are going to have slight variations in their running characteristics.
Jeffery S Ward Sr
Pittsburgh, PA

electrical whiz kid

Jeff;
As I said, it would record the sum of both motors, thus it "sees" the loads as one single one.  The other way, not too too involved, would be to set up a test track with a wattmeter, a simulated load that would be the same for both motors, and check each one separately, thus recording the indivual values.
Rich

Joe323

Perhaps the biggest problem with running two locos on the same track is that unless you are double heading they are likely at some point to crash into each other.

bussy65

Hey phillyreading,

Which 2 train powerpack did you purchase??

I have been looking at the MRC, guy at the train shop said that it lacked power.

Let me know how it works and how many trains are you pulling.

Thanks

Jack