Stay alive Capacitors

[sandy]

Stay alive capacitors for DC locos. I have ordered a couple to test them out on some locos which tend to stall on some dead frogs. I am hoping these capacitors stop stalling and run better. Will let you all know if the testing is successful or not. In the correct section this time.

[Chops]

That would be useful. Do keep us informed.

[sandy]

Have received a couple stay alive capacitors For DC locos, To busy over Christmas and new year but had a look at them now. I tried to put one into a 9F which is DCC ready. There was not enough space in loco for it. But am working on it will keep you posted. I am looking forward to see if it improves the running over my insulfrog crossing.

[508035]

When it comes to matters like this, my main remedy ( ever since I purchased them from maplins electronics when they were open ) has been capacitors that have the negative symbol on them ( I assume they are the polarised variety ).

The pack I purchase had capacitors varying from around 3 volts ( not sure of the microfarad rating ) upto around 400 volts at about 2,000 microfarad.

The main capacitors I have used have been either 2 x 10 volt / 1,000 Microfarad or 1 x 250 volt / 50 Microfarad and these do well in keeping my locos moving over insulfrog turnouts.

I did see a form of stay alive on a youtube video posted on the iron horse railways channel that appears to be around 4 or 5 capacitors like those I use connected together in the format starting either + or - for example for a chain 4 capacitors it would be something like this + - + - + - + - .

I want to point out that this explanation is NOT intended as a take the micky post but to help anyone who may never have used capacitors before to make their own stay alive if they wish to do so.

I once made a stay alive using 3 x 250 volt / 50 Microfarad capacitors for a 7 coach hybrid project based on the old ringfield motored hornby class 110 powered by 2 motors converted to cd motors and with upto 750 volts & 150 Microfarad available although I doubt the 750 volts was ever reached, the unit performed quite well over every formation of complicated trackwork I could run it over, at least, that was until the gears wore out with currently no replacements available in my immediate stock but anyway I hope this might be useful as a possible alternative answer.

[Tricky Dicky]

I think you have some misconceptions about capacitors. The voltage rating you refer to is the maximum voltage that can be applied across a capacitor. Taking an electrolytical capacitor apart will reveal two “plates” tightly wrapped around each other and separated by an insulator called the dielectric which is normally an oil impregnated paper. The overall area of the plates determines the capacitance whilst the thickness of the plate determines the maximum voltage that can be applied. In general use the voltage of a capacitor is immaterial as long as it exceeds the voltage being applied.

Unless I am misreading your post, you go on to say that you are connecting capacitors in series to increase capacitance. When capacitors are connected in parallel the total capacitance is the sum of all the capacitors.

Richard

[508035]

I think it is more likely to be my low level of understanding of capacitors which is purely based solely on my experiences with them. I am by no means an expert in electronics at all and I must also state for the record that any information I give is related purely to that experience.

I have found that even using just a single capacitor, as long as the voltage and microfarad ratings are sufficient enough, that the performance of my locos which have them fitted has been improved and the only reason I find at the moment for any of them to stall is if the wheels create a momentary short or if it a problem within my self made pickup and supply circuitry of the loco concerned.

I fitted a 50 volt / 220 microfarad capacitor into a B12 tender last night ( loco running number 8544 from the east anglian set I believe ) but when I tested the loco again after fitting it was jumping about and stuttering.

Further examination revealed that the tender pickups I had fitted were dirty and the self made loco pickups had lost contact on 3 of the 6 driving wheels 1 on 1 side 2 on the other, the pickups were adjusted and along with another B12 I numbered as 8524 ( formerly 8509 ) the loco now runs double heading a freight working although further remedial work may yet be needed.

[sandy]

My first loco fitted with a test Capacitor is a Hornby tender drive A4 Gillemot which would hesitate when passing over a dead frog point or a crossing. Now she runs over it at a steady pace with out a hint of hesitation. I think I will be fitting a few more of my older locos with these capacitors. Very happy with the improvement of my first loco. These capacitors are not as like the ones used in DCC where locos will run for quite a few inches without power. The DC version will just about gave enough extra power to to go over a dead frog. Just enough to allow the loco to not hesitate on a frog.
Increase in travel distance with out power is up to 46%
I think that makes a £6 capacitor well worth while. There are 2 sizes,and I used the larger 10 mm ones. I was advised that the neater smaller size does not work so well, so I did not order those Capacitor useds is a Hobby Trax Stay-alive Capasitor. Hobbytrax.co.uk. tel 0345 065 4472
Tested both forward and reverse..............Sandy

[Walkingthedog]

That’s great sandy, I reckon they may sell a few more after what you have said.

[Steve M]

I was sceptical when you first mentioned them Sandy but that clearly came from my lack of knowledge. I am pleased to have been proved wrong.
Having fitted over fifty locos with 'proper' DCC stay alives in the last nine months Imknow what a game changer they can be.
Well done.

[sandy]

I have been told by Hobby-trax if a loco is stubborn that you can fit 2 Capacitors which works even better. I have not got that far with the testing yet. That is if you can find space within the loco or tender to fit them in. I had trouble with finding enough space for one in some locos.