DCC wiring harness & shrink wrap tubing ?

"Dragon Heart" wrote

Not come across anything like that, but you might take a look here for some very useful tips on chipping locos:-

Good luck as this might tax your limits depending on the age of the locos. Should not be to much trouble with Hornby as they had a dry run with Zero One. The hardest I have found is Wrenn locos which required replacing one of the brush sleeves with an insulated one.

When you are talking about harness are decoders you have ones with plugs on are they wires only?

Chris

Chris

"Chris" wrote Snipped

Dublo and Wrenn locos typically draw 1amp and more but the Hornby R8215 decoder is stated to be suitable for a continuous motor output current of only 500mA.

I didn't understand the OP's question but shrink wrap is always recommended to cover any soldered joints between wires in decoder installation.

Dave W.

And testing there is no connection path from the pick ups to the motor brushes once installation is complete and before any testing of the loco.

Chris

Chris wrote :-

" Good luck as this might tax your limits depending on the age of the loco's. Should not be to much trouble with Hornby as they had a dry run with Zero One. The hardest I have found is Wrenn locos which required replacing one of the brush sleeves with an insulated one.

When you are talking about harness are decoders you have ones with plugs on are they wires only ? "

I can rebuild a PC no problem but some of my son's loco's are causing problems.

The Hornby Class 25 was no problem, good design to me as it has twin pick up points !

Then onto his Hornby HST Midland Mainline which appears to have an earth 'built in' to the motor so having difficulty isolating the motor.

His Lima Class 20, what are the two coils of wire that look like home made electromagnets that come between the pick ups and the motor ? Can they be discarded for DCC operation or do they provide some sort of assist when starting the loco ?

He's also got a number of 0-4-0 loco's i.e. Percy, Smoky Joe and a Virgin shunter that have the X8987, 59 or 61 chassis assembly. These have no wiring at all, just pick ups that rise up within the body to contact with the motor pick up points directly. Tried to isolate these and connect the track pick up wires from the decoder directly to them but whilst the decoder will make the motor turn the gearing tolerance is so small it slips and the loco will not move.

He also has a R357 with the X.337 motor which I have to repair with a new armature, will I have similar problems with that ?

Chris B

I put one in a Smoky Joe with branchline 2 stage gearbox, mashima motor, romford wheels. It can push a white metal tender without hesitation.

Cheers, Simon

I would think twice regarding "shrink fit " (thermo fit) shrouds. They are permenant and if you have any problems will only make thzm worse -- I would stay with loose sleeving.

It is also much easier to mount chips in the cab of most locos -- the cables take up very little room in the loco body.

Regards

Its the tag on the left hand side of the motor that has a wire going to the block of the motor so remove this or if the tag is touching the motor block isolate it.

Something to with interference suppression and this is included in a decoder it can be discarded.

"Peter Abraham" wrote

Very true Peter, but many of us spend hours trying to avoid the unsightly 'mess' that creates; although I accept it's less of an issue with the enclosed cab of a tank locomotive.

John.

I wrote :- Then onto his Hornby HST Midland Mainline which appears to have an earth 'built in' to the motor so having difficulty isolating the motor.

Chris replied " Its the tag on the left hand side of the motor that has a wire going to the block of the motor so remove this or if the tag is touching the motor block isolate it. "

The powered car has the motor at the rear with two isolated wheels on the 'gearing' side.

The front bogie has it's isolated wheels on the other side with two brown wires feeding from it. One goes to the right hand of the motor ( looking from the geared side ) whilst the other originally went to the front light and then back to the left side of the motor via a black 'in line' capacitor ( which I assume controls the light i.e. forward on / reverse off ).

As both isolated wheels on the front bogie are on the same side they both pick up from the same rail ?

The motor will still run on 12v DC even if I remove the left connection.

The only way I can see to isolate the motor for installing a decoder is the get another set of isolated wheels for the other side of the motor bogie and swap one isolated wheel on the front bogie so I can use these as the pick ups ?

That would probably be a diode for directional lighting an inline capacitor would not allow a DC to turn the motor. ( which I assume controls the light i.e.

Yes

Check the left connection is not touching the motor housing and also try removing the suppression capacitor between the brush holders.

I think I have solved the cause but not necessarily the problem on the HST.

The screws fixing the two metal plates that hold the carbon brushes and springs in place go through a plastic base then directly into the metal body of the motor.

Now I can see two alternative methods of getting past this :-

Get some plastic / nylon screws to replace the originals but they are very small ?

Fit some kind of grommet into the two metal plates to isolate the screws, I have an idea that may work which I will give a go tonight.

Any ideas ?

Come to think of it that was what I had to with a motor. Went to local model shop and got some plastic/nylon screws and worked fine.

Chris

Thanks folks

It doesnt have to be DCC.

I built a layout with 4 branches that was completely automatic using a computer and some basic electronics and relays.

" It doesnt have to be DCC.

I built a layout with 4 branches that was completely automatic using a computer and some basic electronics and relays. "

It does now, as we have just purchased my first DCC equipment !

As I am, what my former work colleagues used to call, a computer geek I know I could have gone down the PC control route but the layout is for my son who has 'special needs' so, despite him being great on the PC, I felt the DCC option was best.

I have created him a wall chart with 00 to 10 on it for the DCC codes with photos of the loco's ... 'James' will be 05 and 'Toby' 07 with his older loco's filling in some of the blanks.