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Discussion Starter · #1 ·
I've read in a few places that swapping a motor on SCX Digital fries the decoder ,
has anyone tried this on Scalextric Digital yet ?

If I go (as planned) to Scalextric Digital I got a fair few cars with Slot.it 25k motors
in them (Mainly slot.it own !) and don't want to have to swap these out for
crappy normal Scalextric ones.

So has anyone tried it or willing to have a go ???

Chris
 

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Julius Wilkko
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... and problems of the digital railways are discovered by slotracers....

If somebody can take detailed picture of a decoder where component codes are visible it is possible to tell how much current you can get without frying the decoder. It may be possible to construct a power booster to be installed beside the decoder. Naturally such booster will draw more power from the control station and power supply which will be the next components to overheat and fry.

Ugrading digital cars with more powerful high-current motors requires more current handling capacity to both command station and decoder. Not an easy task.

Julius
 

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Discussion Starter · #3 ·
QUOTE (lordjw @ 16 Nov 2004, 10:29)If somebody can take detailed picture of a decoder where component codes are visible it is possible to tell how much current you can get without frying the decoder. It may be

So does anyone have these ?
I am guessing and hoping that the Scalextric ones can take the extra power.
Adrian and people at scalextric have always touted that any car can be updated
to have the chip in.

To quote them

QUOTE The retro fit chip can be fitted to ANY car. There are some obvious cars which the hobbyist may find a challenge to fit the chip in to such a small space such as the Caterham, MotoGP bikes, motorbike/sidecar combos, horses, sulkys and cars with no underpans!
Standard non-Digital cars made from 2005 onwards will be made with mouting points on the chassis ready for the hobbyist to convert to digital.
QUOTE Most cars from last 50 years can be fitted with the decode chip. Our latest cars will now have a purpose built chassis to take the decode chip.

QUOTE The conversion of competitors cars to use Scalextric Sport Digital Track is also clarified here.

Scalextric SCX Carrera
Digital Track compatible with standard existing track? YES NO YES
Conversion of Standard Cars to Digital Cars? YES NO NO
Conversion of other manufacturers cars to Digital? YES NO NO
Digital Cars able to race on non-digital track? YES NO NO
Digital racing up to 6 cars on same track? YES YES YES
Digital Track in same scale (1:32) as Digital Cars? YES YES NO

The last one (the table) is the most interesting as they have ALWAYS maintained you can convert other makes cars buy fitting the chip.

Someone out there must have a set by now - come on guys fill us in !
 

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Fouldsc certainly talks sense! One would hope 6 of any of the RTR motors (slot-its, nincos, fly racing etc) will be easily handled by the chips and base; More esoteric and current huingry motors like falcon? maybe not, it would be very useful to have some limits provided.

As for SCX chips frying - even their LED lights for analogue cars seem to fry under SCX PSUs, so maybecompany policy is to run their components very close to the limits...
 

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Julius Wilkko
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So, you want to find out how much power your decoder can handle. I will use PRO-X decoder as an example, hope that picture comes from photobucket without problems.

How much current? Just have a look at the components. Here is a picture of Carrera PRO-X decoder.



... and what can we tell? Firstly guide plus wire goes to a component that is marked "SN1A", hope its visible at the picture. The other end of the same component is connected to motor plus, in other words all current goes through SN1A component. Closer examination reveals (Google SN1A) that this component is a general purpose rectifier diode. Datasheet tells us that maximum AC? current through this device is 1A. With 1A constant current the device temperature will propably increase and when it reaches 100degC, current rating will degrade rapidly. I would say that you could safely have maybe 0.5Amps continuous DC current through this component. You can have instantaneously more that 1Amps when accelerating. This is very rough estimate and there may be some variation with the components.

Can you then upgrade your decoder by replacing the diode with high current model? Nope! PRO-X decoder has transistors BSP100 & BSP250 for motor control. Very rough calculation gives us an estimate how much current those transistors will tolerate. Transistors are surface mounted devices, package type is SOT223. Current through transistor generates heat. SOT223 power dissipation is approximately 5W. We can do very simplified calculation. Full power 12Volts, maximum power dissipation 5W. Maximum allowed constant current is: I=P/U=5W/12V = 0.416Amps. You can draw more current for a short period of time when accelerating.

I emphasize that these calculations are very simplified estimates of the PRO-X decoder performance. You can apply this kind of estimating for Scalextric Digital.

You can prove me right or wrong by experimenting with high current motors. If only diodes or transistors are fried they can be easily replaced with minimum cost. Who will be the first one to try? (...and fry!)


Julius
 

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QUOTE (fouldsc @ 16 Nov 2004, 17:56)QUOTE (lordjw @ 16 Nov 2004, 10:29)If somebody can take detailed picture of a decoder where component codes are visible it is possible to tell how much current you can get without frying the decoder. It may be

So does anyone have these ?
I am guessing and hoping that the Scalextric ones can take the extra power.
Adrian and people at scalextric have always touted that any car can be updated
to have the chip in.

To quote them

QUOTE The retro fit chip can be fitted to ANY car. There are some obvious cars which the hobbyist may find a challenge to fit the chip in to such a small space such as the Caterham, MotoGP bikes, motorbike/sidecar combos, horses, sulkys and cars with no underpans!
Standard non-Digital cars made from 2005 onwards will be made with mouting points on the chassis ready for the hobbyist to convert to digital.
QUOTE Most cars from last 50 years can be fitted with the decode chip. Our latest cars will now have a purpose built chassis to take the decode chip.

QUOTE The conversion of competitors cars to use Scalextric Sport Digital Track is also clarified here.

Scalextric SCX Carrera
Digital Track compatible with standard existing track? YES NO YES
Conversion of Standard Cars to Digital Cars? YES NO NO
Conversion of other manufacturers cars to Digital? YES NO NO
Digital Cars able to race on non-digital track? YES NO NO
Digital racing up to 6 cars on same track? YES YES YES
Digital Track in same scale (1:32) as Digital Cars? YES YES NO

The last one (the table) is the most interesting as they have ALWAYS maintained you can convert other makes cars buy fitting the chip.

Someone out there must have a set by now - come on guys fill us in !
<{POST_SNAPBACK}>


That table is a LOAD of propaganda!

"Digital track in same scale as cars!" HAHAHAHAH! SInce when was the carrera track size ever a liability? And some of the other fields are just wrong.

Its digital warfare!
 

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QUOTE (lordjw @ 16 Nov 2004, 19:42)So, you want to find out how much power your decoder can handle. I will use PRO-X decoder as an example, hope that picture comes from photobucket without problems.

How much current? Just have a look at the components. Here is a picture of Carrera PRO-X decoder.



... and what can we tell? Firstly guide plus wire goes to a component that is marked "SN1A", hope its visible at the picture. The other end of the same component is connected to motor plus, in other words all current goes through SN1A component. Closer examination reveals (Google SN1A) that this component is a general purpose rectifier diode. Datasheet tells us that maximum AC? current through this device is 1A. With 1A constant current the device temperature will propably increase and when it reaches 100degC, current rating will degrade rapidly. I would say that you could safely have maybe 0.5Amps continuous DC current through this component. You can have instantaneously more that 1Amps when accelerating. This is very rough estimate and there may be some variation with the components.

Can you then upgrade your decoder by replacing the diode with high current model? Nope! PRO-X decoder has transistors BSP100 & BSP250 for motor control. Very rough calculation gives us an estimate how much current those transistors will tolerate. Transistors are surface mounted devices, package type is SOT223. Current through transistor generates heat. SOT223 power dissipation is approximately 5W. We can do very simplified calculation. Full power 12Volts, maximum power dissipation 5W. Maximum allowed constant current is: I=P/U=5W/12V = 0.416Amps. You can draw more current for a short period of time when accelerating.

I emphasize that these calculations are very simplified estimates of the PRO-X decoder performance. You can apply this kind of estimating for Scalextric Digital.

You can prove me right or wrong by experimenting with high current motors. If only diodes or transistors are fried they can be easily replaced with minimum cost. Who will be the first one to try? (...and fry!)


Julius

<{POST_SNAPBACK}>

Well, according to you calculations, the circuit doesnt have enough capacity to handle the motors that are in there!
 

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Julius Wilkko
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Hmmmm....

..... and what motors are in there might I ask ? Motors have marking "E200", does not tell me anything.

Julius
 

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Brian Ferguson
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I think Julius is right on with his observations. But what does it mean in terms of motors? I'm only guessing here, but I suspect that even a Rabbit or Fox may be pushing the decoders to their limits, and L'il Rippers or Falcons.... not a chance! Components rated at 1/2 amp or so won't live long with motors that can draw 4-6 times that or more.

The train world went through this too. The original decoders in RR couldn't handle some of the more powerful motors and the manufacturers responded by upping the max current capacity of their decoders. Will this happen in slots? Probably... but I wouldn't hold my breath waiting for it... it took several years in the train world.

I'm actually a bit surprised that the slot manufacturers didn't learn from the train guys and build high-current decoders to begin with.

Hopefully, I'll be proven wrong, but I doubt that motor upgrades will be a viable option on digital cars.
 

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QUOTE (lordjw @ 16 Nov 2004, 20:00)Hmmmm....

..... and what motors are in there might I ask ? Motors have marking "E200", does not tell me anything.

Julius
<{POST_SNAPBACK}>

I have the Pro-X set and the cars have the same acceleration and power as the analog models.

These "standard" motors are generally understood to draw 1.2amps. I have not opened the cars yet.

Your analysis may be true, but are you sure that the power from the track is going through those components? The carrera track supplies full DC power so there is no conversion from AC to DC going on.
 

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Julius Wilkko
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Darainbow, yes - the motor power goes throuh these components. And as I said, you can draw more current, maybe that 1.2A or even more, but just for a short period of time. Acceleration from zero to full speed will consume more power but as the car is moving the current consumption is decreased.

Julius

PS.
Waiting for the Pro Digital pics.....
 

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Julius Wilkko
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Astro, Microchip Dallara Indy is unfortunately just a regular slot-car.


Julius
 

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Cheeky buggers having analogue promotional cars! But still, collectable!

I guess with chip temperatures rising, cars with open vents will do better; time to start cutting up bendy straws to make some ducting...
 

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Discussion Starter · #17 ·
Julius ,
Thanks for your info on the Pro-X system , I am guessing you have one.
Your calcs even add up ! (I know a thing or two about electronics also and like
you just given the part numbers on the Scalextric decoder could solve this riddle).

The difference I see is that Carrera and SCX have always maintained that there
systems are just for car they make and you can't put it in any other. So swapping
motors in them cars for hotter ones and the circuits frying does not surprise me in
the slightest.
Scalextric however has always maintained that they will be selling chips to upgrade
old cars AND to put in other makes cars.

So I am hoping (I really am !) that they been sensible and rated these things to 3amps
or more.

I see from pictures on the web (home racing world) that the standard powerbase for three cars on digital is kicking out 12V 2.5amps (so 0.8 per car) . Which is not alot.

So I put this appeal out - if you got a Scalextric digital car - can you open it up and
take a good photo of the circuit board on both sides

Ta
 

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Julius Wilkko
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Hi, fouldsc, others

Yes, I have Carrera PRO-X and considering order for both SCX and Scalextric digital sets so that I could make in-depth comparison between the three. Maybe I should ask Sean at Pendle if he is willing to give me a good offer for both SCX and Scalex digital sets. £400 is a lot of money.

Julius
 

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As soon as I saw this - Ive tried to do as requested - except - my camera aint up to the job.... It wont take a photo good enough at such a close distance.
CoolS
 

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coolscientist - maybe reading the numbers off the chips and telling them to Lordjw Fouldsc will be a start... obviously the way the circuit is configured can add protection, but it might be a start..
 
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