Removing Surface Mount Capacitors

[wcohen]

All,

All or most Bachmann locomotives come with information regarding removal of the (Europe required) capacitors on the motor for better performance on American DCC systems.  On newer models, surface mount capacitors are used on the PC board instead of on the motor.  Which ones should be removed?

Model in question is a Bachmann 44 Tonner.  There are five or six surface mount capacitors, labeled C1 - C5 or C6.  Again, which ones should I remove?

You would think that Bachmann's service department should know the answer; however, they referred me to this forum.  That sure doesn't give me much faith in their service department, but that's another story.

Thanks for any and all assistance.

Wayne

[Len]

If you're talking about the 'DCC On Board' version of the 44-Tonner, I wouldn't mess with it. I operate mine "stock out of the box" using an NCE Power Cab with no problems at all.

Len

[brokenrail]

I totally agree with Len .They are like a electrical noise shock absorbed in layman's terms that knocks down the noise from the motor.If they short it would be a dead short and the loco would not run.It has no adverse effect other then that.I have seen a lot of talk about these and by removing them ,your removing added protection also to the circuitry on the board if you do.Old Saying .If it aint broke .Don't fix it.If it is not running right .It is something else.
Johnny Adam

[rogertra]

They are TV noise suppressors.  They are required in Europe so your model trains do not interfere with your neighbour's TV picture reception.

Cheers

Roger T.

[wcohen]

All,

Thank you for the opinions, but without going into detail I've seen the improved performance of other Bachmann models once the motor caps are removed.  I've seen the noise they create in the DCC system when they are not removed.  I just want to know which ones to remove. 

Thanks,

Wayne

[jbrock27]

I have experienced that as well, removing them for DC operation.

[brokenrail]

All,

Thank you for the opinions, but without going into detail I've seen the improved performance of other Bachmann models once the motor caps are removed.  I've seen the noise they create in the DCC system when they are not removed.  I just want to know which ones to remove. 

Thanks,

Wayne

Wayne, They do not create noise they suppress them .They are used in many applications in the automotive computer control circuitry that deals with output controls.All motors create electronic noise when poles are switched.Sometimes spikes that can destroy integrated circuits .I  myself survived the automotive change over from standard electronics to base computer control and had the term diagnostic tech labeled.Retired now.It is a fact not a opinion.Removing them can cause more harm then good in the dcc world.If you have a dc loco and use this motor with the caps on it and add led lights and do not install a cap in the circuit .You will not have a reverse light flicker .If you do not use one with caps on it you will .Eventually the leds life will be cut short  because of the electrical spikes caused by the build and collapse of the magnetic field of the motor .
Johnny Adam

[wcohen]

All,

The issue of noise is really beside the point.  I and others in my club have seen the improvement in the ability to program Bachmann locomotives once the motor capacitors are removed.  Sometimes, the ability to program other locomotives (programming on the main) is hindered if a Bachmann locomotive is on the main somewhere.  I don't want to remove ALL of the capacitors - just the ones related to the motor.  I suspect it's some combination of C1 and C2 with the others used for anti-flicker. 

I find it shocking that Bachmann suggests doing so in the literature provided with the locomotive, yet they cannot find anyone who knows which ones to remove.

So let me rephrase:  Which are the surface mount MOTOR capacitors that Bachmann recommends removing from the 44 Tonner?

Thanks,

Wayne

 

[AGSB]

If you are determined to do it, go here https://sites.google.com/site/markgurries/home/technical-discussions/decoder-motor-drive/motor-capacitors/bachmann-engines

[wcohen]

Hi AGSB,

Thank you for the response.  Unfortunately, the links show examples of the ceramic capacitors, but not the surface mounts.  I like the idea of using the stock board if possible because it holds the LEDs in place and makes for easy connections.  I'm about at the point where I will scrap the whole board and just wire in the best after market decoder that will fit.

Wayne

[AGSB]

Have you tried contacting the manufacturer of your decoder and see if they can help?

[wcohen]

It has the stock, Bachmann decoder in it. 

[Len]

According to a thread back in 2011, if you're going to remove the SMT capacitors on the 70-ton and 44-ton locos, you remove all of them.

The comment specific to those locos is here: http://www.bachmanntrains.com/home-usa/board/index.php/topic,18019.msg145415.html#msg145415

But I would suggest going back to the start and reading the entire thread.

Also, I believe Lenz makes the "stock" Bachmann non-sound decoders to Bachmann's specs.

Len