News:

Please read the Forum Code of Conduct   >>Click Here <<

Main Menu

DCC Loco Break In

Started by mitremark, February 25, 2009, 12:55:09 AM

Previous topic - Next topic

mitremark

I read on a post that you should break in a DCC loco on a DC system but I cannot find that post and do not remember the details, so what is the best way to break in a new DCC Loco?

Yampa Bob

#1
Just run the loco both directions at varied speeds. Check for any sluggishness, binding or noises.  Most locos will break in within 30 minutes, some take a bit longer.  

Regards
I know what I wrote, I don't need a quote
Rule Number One: It's Our Railroad.  Rule Number Two: Refer to Rule Number One.

boomertom

Bob,

I am curious as to why you suggest breaking in on DC?


Although I suspect the majority of those just starting in the hobby still begin with conventional DC sets, Bachmann does market several sets with the E-Z Command as the sole power source.

The recommendation to break in on dc would require the purchasers of those sets to also acquire a conventional power pack thus adding to the start up cost.
Tom Blair (TJBJRVT68)

Rangerover

I think it would be wise to check the lube in the gear boxes, some are overlubed and some are dry from the manufacturer.  Also steam loco's should have the rods and levers lightly oiled with a plastic friendly oil. Auto trans fluid, hair clipper oil or labell.

mitremark

Bob,
Thank you for your input, as always it is very informative. 

Rangerover,
Will check fluid levels as well, I did not think of that. Thanks

Jim Banner

The only reason I am aware of for breaking in a decoder equipped locomotive on dc is that you can conveniently do it on a separate track.  Many model railroaders end up with a spare dc power pack or two and enough sections of track to set up a circle, or better, a figure eight break in track.

If you don't have a spare power pack or the extra track, by all means break your decoder equipped locomotive in on DCC.

Having said that, if you have a new locomotive without a decoder, break it in and tune it up before you install a decoder.  That way, if you have any problems after installing the decoder, you will know that they are not caused by a faulty mechanism.
Growing older is mandatory but growing up is optional.

Yampa Bob

#6
Modelers who buy DCC controllers from the start usually end up acquiring a conventional pack for the AC accessories terminals anyway, so the extra cost shouldn't be an issue.  In the event your DCC controller malfunctions for some reason,  you can use the DC controller to keep rolling.
I know what I wrote, I don't need a quote
Rule Number One: It's Our Railroad.  Rule Number Two: Refer to Rule Number One.

Jim Banner

Bob, I am glad your methods work for you.  And we all appreciate your willingness to share them.  But there are a couple of errors in your reasoning which I think might be the result of not fully understand analogue conversion in DCC decoders.

If you can measure locomotive current on dc, then you are only a bridge rectifier and a capacitor away from measuring same on DCC.  In either case you will get the same errors in you are using a cheap, non true RMS meter, but the results are close enough.  The advantage of measuring with DCC is that you have something to refer back to if you run into performance problems in the future.  I will refer to the old question, "does this locomotive need lubrication now or is it running okay?" later on.

Motor heating is virtually identical with dc and with DCC, as long as there is a decoder involved.  If you can change the locomotive over to dc (e.g. unplug the decoder and install a dummy plug) then you may have a little less heating.  But this does not give a true picture of how warm the motor will be when you ultimately run on DCC .  With DCC, you have the decoder as an added source of heat.  The reason the heating is virtually identical with the decoder in place is because the waveforms applied to the motor are very, very similar, whether you use DCC or full wave rectified dc as put out by virtually all power packs.  The reasons are long and involved, but we can go into that and look at some waveforms at another time if you wish.

The noise from a motor running through a decoder is the same whether the decoder is powered by DCC or the full wave rectified dc from a power pack.  Again because the waveforms are so similar.  The only time the noise is lower on dc is if it is pure, filtered, regulated dc from a laboratory type power supply.  Not many of us have access to these.

Draw bar force tests can by done with your handy dandy force gauge (link needed) on either dc or DCC.  But if you plan on using DCC as your normal operating system, it makes more sense to do them on DCC.  Then you do not have to convert back to dc to repeat them down the road, if you feel you are losing draw bar pull.

Testing a motor is something you can do with a dc power pack that you cannot do with a DCC booster.  But if you are advocating that people do this, please remind them to either disconnect the motor from the decoder or make sure the locomotive off the track.  If you apply power to the motor with either dc or DCC on the rails, and you have forgotten to disconnect the motor, you will destroy the decoder.  Once you have disconnected the motor from the decoder, you can also test it with a 9 volt battery.  This has the advantage of limiting the applied voltage to a safe level.  Some power packs put out enough voltage to over speed some motors, causing them to fly apart internally.  That too is a story for another time.

Fortunately, your locomotive does not have to be any more perfect to test it and break it in on DCC instead of on dc.  The one exception to this would be if you installed your own decoder without first measuring the locomotive's lock rotor (stalled motor) current draw.  Then you run the risk of having an inadequate decoder for that locomotive.  When you buy a locomotive with the decoder already installed by the manufacturer, he has already taken care of that problem for you.  What he may not have done is provide any method for disconnecting the decoder without invalidating the warranty.  In this case, you end up testing and breaking in with the decoder in the circuit, whether you use dc or DCC.  If the motor is shorted from the get go, you will end up sending your locomotive in for a new decoder as well as a new motor, no matter what you used for testing and break in.  If you do not want warranty, then by all means disconnect the motor by whatever means, and test it on dc.  If the manufacturer has provided some means of disconnecting the motor (such as an 8-pin plug and socket, then testing the motor on dc is a good idea, subject to the warnings above.

While I obviously do not agree that Bob's break in methods are the only suitable ones, I heartily agree on having a test and break in program in place for your railroad.  I think what matter more than the details of the methods you use is that you are consistent in their application.  That, and making notes on each locomotive, are extremely useful when you have to deal with these same locomotives at sometime in future.  In a perfect world, all our locomotives would have hour meters to tell us when to relubricate them.  Then next best thing a quick test to see if they need lubrication.  If you know how much current your locomotive should draw under a given set of test conditions, it takes only seconds to measure that current and know your locomotive is either running fine or is due for a trip to the lube rack.

I also agree with Bob's forethought in having extra command control systems and dc power packs on hand.  Nothing is worse than arranging a train show, then have the whole layout quit at the last moment.  An "in orbit spare" can save the day.  Our club's large scale portable layout includes spares for everything - command station, boosters, transformers, radio receiver, throttles and so forth.  We have only had a problem once, and that was a blown command station right at the start of a show.  It sure nice that we could reach in a box and pull out a spare, already programmed, and keep running as if nothing happened.  When you figure five guys, and their wives, meals for 4 days, 3 nights in a hotel, and the costs of transporting the people and the layout to and from a weekend show, a spare system starts looking awfully cheap.   
Growing older is mandatory but growing up is optional.

boomertom

I suspect if I had the funds available for three E-Z Commands I would have gone with a more advanced system and been even more upset by down time due to repair delays.

I do have available a perfectly adequate dc paower pack -p a 30 something year old MRC Tech II 2500, which has proven useful and would allow me to set up a test bed for running in a locomotive.

Therefore should I be asked for a suggestion by anyone wanting to get started with Bachmann and DCC I will suggest purchasing on of the E-Z Command/.lococombos and a DCC on Board trainset with the standard power pack. Maybe a little more outlay, br maximum utilization.

Tom

Tom Blair (TJBJRVT68)

Jim Banner

#9
Bob, I think we agree on more than we disagree on.  But your original reply to mitremark could be misconstrued as meaning break in on only dc, leading him to buy a dc power pack that he could do without at this time.  He may have a dc pack but he could equally as well be running his lights, turnouts etc. off a fixed voltage wall wart.

I seem to remember saying something about not installing decoders in locomotives until you have them working well.  And I stand by that.  But when the locomotive comes from the manufacturer with the decoder built in, you are often forced to test it and break it in through the decoder.  I suspect mitremark fell into this category with his new DCC on board locomotive.

Bottom line, and I hope we can both agree on this -

- if a locomotive has no decoder or the decoder can be unplugged and replugged, then the locomotive should be tested, broken in, and tuned up on dc before installing or replugging the decoder.  This will protect the decoder if there is something seriously wrong with the locomotive.

- if a locomotive already has a decoder that cannot be easily removed, then the locomotive can be tested, broken in, and tuned up on either dc or DCC.  If there is something seriously wrong with the locomotive, this may damage the decoder.
Growing older is mandatory but growing up is optional.

grumpy

Jim
I would like to add my 2 cents . This is not to disagree with either you or Bob who are both much more knowledgeable about the electronics than I am. I always test my locos when I first get them on DC . The purpose is to elimiinate as many outside factors as possible such as the command station should any problems occur. If I do find a problem then I know it is within the loco . In most cases the problem is covered by warranty and the easiest way to void a warranty is to disassemble and reassemble a product and then send it in for warranty. As Bachman prefer is to send it to the place of purchase and have them send it back to the factory. The mfg would be perfectly within his right to refuse warranty if he sees that the item has been tampered with.
If no problems occur while running the loco on DC I will then run it on my layout with my DCC system . If a problem the occurs I will test the loco on another system to eliminate another factor .If it runs fine then the problem is in my system . If it doesn't run properly then the problem is in the loco and it goes back to the place I purchased it from and have them look after the warranty.
No where in this procedure have I take a screwdriver or soldering iron to the loco. I have let the mfg take of the problem since it is his.
I have set up a special test track for my testing.
I will add a couple of sayings ( if you don't know what you are doing don't do it ) , If it ain't broke don't break it ) . I am not referring to you. Thanks for listening.
Don :)

pdlethbridge

I want to put in a couple of more pennies too. If all you have is a DCC layout and no DC test track, it would be crazy not to test in DCC. So if you have one system, and only one system, thats what you have to use.
I have been installing decoders in engines for my brother who has a duel system, DC and DCC. He is switching every thing over to DCC. Expensive yes, and in the long run, easier. His control panel is a nightmare, any time it has a problem, I get to fix it. He has over 30 DPDT, switches, 6 wires each for the blocks. All his switch machines (30 +) are switchmaster motors with SPDT switches for each one, 3 wires each So, at a minimum, there are 270 wires on that control panel. Its a mess and we can't wait to get the buss in.
I don't do any of his conversions at his house, I do them here. Its much easier. So, bottom line, I make do with what I have.

Jim Banner

Thank you both grumpy and pdlethbridge for helping make my point.  You really do not want to be unsoldering and resoldering factory installed decoders.  This would void your warranty.  Unplugging a decoder and plugging in a jumper is fair game - the manufacturer includes the socket for your convenience, not his own.  Incidentally, I have edited my previous post from "easy to remove and reinstall" to "unplug and replug" to emphasize this. 

Testing on dc or DCC with the decoder in place is fine too.  Just remember that when the decoder is installed, the power to the motor has to go through the decoder, whether it is running on dc or DCC.  If this destroys the decoder because of a serious mechanical problem, then it is the manufacturer's problem and by all means use the warranty, if you have one.

This still leaves the question of what to do if you do not have warranty on your new locomotive.  This can happen for a number of reasons including buying a new locomotive off eBay from someone who is not an official dealer.  If you are the cautious type and you feel comfortable disconnecting/reconnecting a decoder, then by all means protect the decoder by taking it out of the circuit and do your mechanical testing on dc.  If you boldly go where angels fear to tread, by all means test your new locomotive on dc or DCC with the decoder in place.  And if you are of a cynical nature, open up your new locomotive, power it up and see why the seller was getting rid of a brand new unit.  I will plead guilty to being one of those "boldly go ..." guys and on rare occasions, have lived to regret it.

If you don't have a warranty to fall back on, I suppose it all comes down to a personal decision based on your guess of the likelihood of a serious mechanical problem vs. the likelihood that you will damage the decoder vs. the cost of a replacement decoder vs. the extra time it takes to do it.   
Growing older is mandatory but growing up is optional.

James in FL

Mitremark,

Always check for proper lubrication before running a new loco. I clean and re-lube them again after about 8 hours run time.

The purpose of running a motor at various speeds and in both directions is mainly to wear the brushes into a concave surface providing maximum contact between the brushes and the commutator.
That's it.
This current draw can be measured with a Multimeter when first new then again after a few hours run time to see how this works.
I am not sure what useful information, if any, could be gathered by measuring draw before this process has been completed.
During that same time, the mechanical components (gears, bushings, bearings, etc.) are beginning to wear, increasing tolerances between them. In effect causing "slop", or what some may perceive to "breaking- in". Over time, as wear continues, the drive mechanism becomes "loose" and naturally, there is less binding between parts causing a smoother running locomotive, thus reduced load on the motor.
The idea to "break-in" on DC rather than on DCC is that you can remove one variable from troubleshooting (the decoder from the mechanical).

I have no desire to control with DCC.
To me, "breaking in" a locomotive for hours at a time is pointless. Motor brushes have a limited life. Why waste some of that life when the loco can be utilized on the pike? It will wear out just as well on the mainline.

"Breaking in" is highly overrated and the term is a misnomer at best.

Although measuring current draw to determine when one "should" lubricate a locomotive may be helpful to a point, it is certainly not a necessity to do so. A higher draw does not necessarily mean it's related to insufficient lubrication. A loco that's squealing, getting hotter than normal, or slower running than usual, is an equally good indicator.

The hobby is not as complicated as some make it to be.
The "right" way is "your" way.

Good luck.




mitremark

I would like to thank everyone for sharing their views. They all have been very insightful. Thank You.