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Discussion Starter · #1 ·
We may have covered this before however it does seem that there is a lot of confusion over what to do with capacitors fitted to locomotives and other parts of the control grid.

It seems that some manufactures suggest that you can leave them in and others suggest that you can remove them and others are undecided what to do. Locomotives that are "DCC Ready" come with capacitors. Even locomotives that are "DCC Fitted" come with capacitors. Some power clips have capacitors although the "official" ones for use with digital control do not. It is a very confusing picture.

Is there a simple definitive answer or a set of rules?

Happy modelling
Gary
 

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I say cut 'em off!!!
Technically, the results will vary depending on what the decoder is sending to the motor and whether it uses back EMF, however not having the capacitors there will not have a negative effect on the performance whereas leaving them there probably will.
On principal, decoders should comply with whatever local RF suppression regulations apply to the area in which they are sold and should not rely on the manufacturer of the model having done so already.
Furthermore, any decoder manufacturer who refuses to state categorically (when asked) whether or not the capacitors should be removed is....

bad.
 

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Any on the power clip should definitely be removed.
For locos, if it works with the capacitors present then leave them, otherwise remove them. Some decoders are more sensitive to the presence of capacitors than others. However it is easier just to cut them all off regardless.
 

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Discussion Starter · #5 ·
So is the definitive answer to remove all capacitors 100% in all cases even if "DCC Ready" locomotives have them fitted and even if "DCC Fitted" or "DCC Onboard" have them fitted?

Can I refer whoever to this thread in due course?


Happy modelling
Gary
 

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DCC ready have capacitors as there is a chance that the loco will be run without a decoder on DC.

If a DCC Fitted/DCC Onboard loco has capacitors, leave them in if the loco works fine. If there is any erratic behaviour or shorting of the command station due to the loco, remove the caps as this could be a cause.
 

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Heh! Heh! I have to laugh. What about those companies who offer "DCC Fitted" or "DCC Onboard" and fit capacitors and state that you can operate your loco on both DC and DCC layouts. What are the implications of removing the capacitor in these circumstances for DC use even if one is not required for DCC?

You would suggest leaving the capacitor in place in such a circumstances?

And if you have no intention of running on DC would you susggest removing the capacitor?

And what about those companies who offer decoders which can permit your loco to run on both DC and DCC? If you fit one of these and you do run your loco on both DC and DCC layouts what is the capaciter position then?

Would you suggest leaving the capaciter in place or removing it regardless?

I do seriously want to clear this up once and for all and have an answer that is consistent for all conditions and circumstances irrespective of decoder manufacturer!

Is this actually possible?


Please answer "Yes" if a 100% definitive answer can be given that leaves no room for doubt and that can be offered up in the form of a logic table.

Or "No" if it is down to performance criteria and the answer is not 100% black and white but a shade of grey.

Happy modelling
Gary
 

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QUOTE (Gary @ 26 Jan 2007, 12:02) <{POST_SNAPBACK}>Heh! Heh! I have to laugh. What about those companies who offer "DCC Fitted" or "DCC Onboard" and fit capacitors and state that you can operate your loco on both DC and DCC layouts. What are the implications of removing the capacitor in these circumstances for DC use even if one is not required for DCC?
DC or DCC is irrelevant for DCC fitted locos since the decoder is always in circuit. The motor is always being driven by the decoder and the capacitor will have the same effect (or lack of) whether you run on DC or DCC.

QUOTE You would suggest leaving the capacitor in place in such a circumstances?
As suggested, if it works, leave them in or, if it aint broken, don't fix it.

QUOTE And if you have no intention of running on DC would you susggest removing the capacitor?
See above.

QUOTE And what about those companies who offer decoders which can permit your loco to run on both DC and DCC? If you fit one of these and you do run your loco on both DC and DCC layouts what is the capaciter position then?

Would you suggest leaving the capaciter in place or removing it regardless?
See above.

QUOTE I do seriously want to clear this up once and for all and have an answer that is consistent for all conditions and circumstances irrespective of decoder manufacturer!

Is this actually possible?
I have never heard of a case where removing the suppression components did not work. That is the only answer that can apply under all conditions. Otherwise there are too many variables in the choice of decoder and the type/quantity of suppression components fitted.

Suppression components should always be removed from power clips. They should not be confused with the filter components (Resistor and Capacitor) sometimes used on larger layouts.

Andrew Crosland
 
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