Is it possible? I own 2 AC Roco loco for marklin system and because i jumped to DCC system i would like to convert them to DCC.They have a motorola decoder.How difficult is it?
it depends on how the engines picked up power from the track.
If they are 3-Rail (like Lionel):
For starters you’ll need to convert the pickups so that you can pick up power from either side of the track with the drivers (left or the right) - I don’t know if they make (replacement) drivers that can pick up power from both left AND right tracks at the same time…
You’ll then need to convert the tender so that it can pick up power from the other rail, and install a jumper wire between the motor and the tender.
You’ll also need a DC motor - from my (limited) understanding of AC and DC the motors work differently, so you can’t use one type of motor with the other power source…
After that, its just a matter of rewiring the locos so that the motor gets power, and doesn’t short out.
If they are 2-Rail for the AC pickups then you pretty much will only need to swap out the motor for a DC unit, well and install a decoder in it.
The locos are coming out from Roco in two versions.One for AC and one for DC.But i don’t know what are the differences between them.If it is only the pickups then it should be easy.But i must be certain that the decoder and the motor are the same in both system.I will use them with DCC and somewhere i heard that AC digital and DCC use both AC current on the track.Is that right?
It’s almost a certainty that you will have to change the motor out. Very few AC motors will work on DC.
No, DCC does not put AC current on the track – it puts a high-frequency square-wave DCC command signal superimposed over DC track power. This is not AC in the same meaning as applied to your Roco AC powered locomotives.
Trying to modify AC powered locomotives to run on DCC is likely to be more technologically complicated and expensive than it would be to simply purchase new enignes.
Ok,probably i will sell them.
how is it complicated? I mean, sure he has to swap out the motor, and maybe the drivers/tender wheelsets, it should take no more than an hour or two. The most complicated part would be making sure that the fram is isolated the right way to allow for DCC operation…
Why? There is no reason DCC can’t be used on three rail track. The center rail is one conductor and the outside rails are the other. In fact it is easier with three rail because one doesn’t have to worry about reversing loop issues.
I believe all one would have to do is convert the motor.
very true!
Unless those AC units (as I was assuming) are 3-rail, and he only had 2-rail DC (which has since been converted to DCC)
Yes they are 3-rail and i want to convert them to 2-rail DCC
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Almost anything is possible given enough effort.
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Detailed knowledge of the locos is critical to know how much work is going to be involved.
Do the locomotives use the center pickup? That has to be changed. Most AC locomotives do not have insulated wheels - wheels on both sides pick up for one “wire” to the decoder/motor, with the center pickup providing the other “wire”. The conversion involves installing insulated wheel sets, and rearranging power pickups to pick up from the 2 rails. How best to do this would require detailed knowledge of the locos.
The decoder will have to be replaced with a DCC decoder.
The motor itself may or may not be a DC motor. Many-to-most current AC loco production uses DC can motors with a rectifier/decoder/controller in front. A lot of older AC loco production used universal motors which run on either AC or DC just fine. So the motor may or may not have to be replaced. Again, detailed knowledge is required.
Because of the work of replacing/insulating the wheel sets for 2 rail operation, most modelers do not bother with these type of conversions. However, if replacement insulated wheel sets are readily available from Roco, than the job might not be so onerous.
my thoughts, your choices
Fred W
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Almost anything is possible given enough effort.
-
Detailed knowledge of the locos is critical to know how much work is going to be involved.
Do the locomotives use the center pickup? That has to be changed. Most AC locomotives do not have insulated wheels - wheels on both sides pick up for one “wire” to the decoder/motor, with the center pickup providing the other “wire”. The conversion involves installing insulated wheel sets, and rearranging power pickups to pick up from the 2 rails. How best to do this would require detailed knowledge of the locos.
The decoder will have to be replaced with a DCC decoder.
The motor itself may or may not be a DC motor. Many-to-most current AC loco production uses DC can motors with a rectifier/decoder/controller in front. A lot of older AC loco production used universal motors which run on either AC or DC just fine. So the motor may or may not have to be replaced. Again, detailed knowledge is required.
Because of the work of replacing/insulating the wheel sets for 2 rail operation, most modelers do not bother with these type of conversions. However, if replacement insulated wheel sets are readily available from Roco, then the job might not be so onerous.
my thoughts, your choices
Fred W
Ah, now I understand. In that case it might be better to consider this as two separate conversions. 1. Convert to DCC. and 2. Convert from three rail to two rail operation. The order which they are done doesn’t matter, but it would help clarify which item people are addressing in their posts.
In this case as the prior poster also stated, I believe the hardest part will be isolating the power across all the axles, and to be of more help we would need to know more about the specific loco. Is it possible to post pictures?
Well after a closer examine of the locos i found out that the wheel are isolated across the axles.So here no broblem
At the techical data of the loco it says.
Outputs:
-Motor circuit,max.current load 1,1 amp.,overload protection;
-4 outputs, 2 of themfor illumination, 0,3 amp max. load for eachoutput, max.additive load for all outputs 0,3 amp each simultaneously.
Connection: standardised interface; polarity designations according to NMRA S 9.1.1 and NEM 650/652.
Also to the replacement parts it shows one motor for both AC and DC versions but it shows different wheel sets.I dont know why but probably the wheels must be different because i tried the loco on a roco track code 83 and the flywheel are so big that are touching the ties.
Here are some fotos.You see 4 black cables 2 to each side taht comes from the contacts to the wheels and the brown cable that comes from the center contact.All 5 cables are isolated between.So i think if i split the 2 black form one side and connected them were the brown cable is should be ok.
The only thing that it should be replaced is the decoder.
Is there a way to shorten the flywheels?
rom your photos i don’t see any flywheels… but you should probably remove the third-rail pickup as you make the conversion so that it doesn’t get fouled up on something.
It appears that you are calling the wheel flanges, flywheels. The wheel flange is the part that hangs down inside of the tracks - and keeps the wheels on the tracks. If this is the case; it is a machine shop cure by turning down the wheels. This is a major job; not easily done at home. Most of us that use older loco’s just use code 100 rail to avoid this problem.
You are right! [8)] Wheel flanges not flywheel.
Finaly i put a DCC decorder made the changes to the cables as i wrote before and it work!!I have a DCC loco now!