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Hi All,

I was wondering about power supplies for a routed wood digital track. I will be using a maximum of 12 cars (2 lanes with 3 lane in sections) and I would image around 24 Lane Brain's plus solenoid and flippers. Can anyone recommend a good supplier?

I'm guessing I will need a 240VAC to 12 VDC @ 40 to 50 Amps.

I was thinking of using two of these:

https://www.jameco.com/z/ERPF-400-12-MEAN-WELL-12V-30A-360W-Enclosed-Switching-Power-Supply_2253925.html

Any comments of suggestions greatly appreciated.

Thanks a lot

Dave

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novice jazz player &
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I am sure Scorpius system users will have great advice and experience to share...

In addition maybe the following thoughts are helpful?

1/ it is generally unsafe practice to parallel wire the outputs of two separate dc power supplies to achieve increased current drive unless the manufacturer has specifically designed the power supply output circuits for this purpose. If so this would be clearly stated in the spec sheet. If not dont risk it.

2/ ensure the design has a correctly functioning (and adjustable) current limit circuit. Remember the voltages and currents referenced here are similar to arc welding stations so even a simple track short could become a hazard if the correct safety features are omitted.

3/ adjustable output voltage could be useful too if you may want to adjust max throttles across the full race pack e.g. some raceways run at 11.5V not 12V nor 13.8V.

4/ to get a good idea of which currently available power supplies are routinely in play, the websites of the suppliers of hardware for the larger raceways are worth a look. Some nice single units available in the 100-200 Euro/GBP price range.

c
 

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...

I'm guessing I will need a 240VAC to 12 VDC @ 40 to 50 Amps.

...

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12 Cars = 7.2 Amps ($599.40 - average Amperage?) Calculated with each car drawing .6A (I personally don't have a car or truck that draws more than this)

24 Lane Brains ($1440 - up to 48 Flippers) = 9.6 Amps (average?) Calculated with each LB drawing .4A - these are wired directly to the rails

TOTAL Amps = 16.8 (based on above guesses)

(I'm well aware cars pull more amps in stall or standing start, however my cars don't draw more than stated above)

I'm guessing a 20A power supply will do... bump it up to 30A for good measure. Can you show your calcs for 40-50 amps you think are necessary? Perhaps I missed something...

4 Scorpius Controllers - $636

USB Dongle - $80

TOTAL SCORPIUS COST = $2755.40 Not Including Track and more cars. That's a Substantial investment!!! and I'm sure I missed something!
 

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Prof I T
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20 amp continuous 30 amp peak smoothed regulated psu is all you need
thumbsup.gif


Scalextric uses two 4 or 5 amp psu to power upto 6 cars and the xlc etc.
 

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. I will be using a maximum of 12 cars
What sort of motors are in those cars?

That's crucial because some motors take much more than others. Scorpius chips allow the use of considerably higher current motors than (for example) Scalex chips

There are replies above that assume you are using something around stock Scalex motor currents, Sure they might have guessed right and 40 to 50 Amps is overkill.
 

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2/ ensure the design has a correctly functioning (and adjustable) current limit circuit.
Protection against damage from short circuits is an important point. Obviously there has to be enough current to run all the cars properly, but much more current than is needed isn't a good idea.

In digital all the cars have to be run from the same supply, but the power for all the lane changing stuff doesn't have to be run from the same supply.
Therefore, it's an advantage to wire the power to the cars separately separately and limit the current to no more than necessary - either with a dedicated power supply with an adjustable current limit OR by a circuit breaker or fuse from a common power supply.

Obviously there is some risk of something shorting out the track power rails / tapes / braids. There's probably a much smaller risk of a short circuit in the all the lane changing stuff, but it's probably a sensible precaution to limit the current in that circuit.
 

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novice jazz player &
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Hi 300SLR, probably not for this specific thread but I do wonder if we could be more clever in how we design the current limiter circuits for slotcars... particularly if we are bringing 40A power supplies into play. I would imagine the times when very high current draw is likely could be predicted with reasonable accuracy from throttle settings and timing with respect to race start events and removal of yellow flag events etc. Probably should start a thread elsewhere on the forum to discuss further.

c
 

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Hi Dr_C

Agreed it's worth discussing and I think it's much better to start a new thread than tack it on to the end of this one.

Maybe the digital forum rather than this one - it's not just an issue for Scorpius.
Digital has the feature that the powers is on the rails/ tapes / braid whether or not a driver is pressing his controller. That does increase the risks in the event of a short across the rails.

I suppose you could expand it to talk about all slot cars. There might be something to learn from the over 50 years experience of using non-digital tracks with 40 amps + per lane. However the digital power on all the time business means that experience isn't all that applicable.
 

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novice jazz player &
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Is the Fusion 600W a good choice?
c
Interesting... the Fusion 600W has a user adjustable current limiter but not a user-adjustable overload cut-out (threshold trip). I.e. if running twelve cars (3A/car) the current limiter would be set to 36A. If this current is reached the power supply starts to reduce voltage to ensure the current setting is not exceeded. It does not trip-out. So a screw which falls onto the rails would be heated with 36A. Therefore I believe some other form of circuit breaker is required too IMO.

What is normal practice with these large high current raceways?

c
 

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What is normal practice with these large high current raceways?
Digital high current raceways? I'll leave it to the digital specialists to answer that one.

Non-digital? There's no universal standard.

Commercial tracks with 3 separate controller hook ups often had a fuse in the brake wire (some used a self resetting fuse). This provides protection against the controller being hooked up incorrectly, which is probably the largest risk with this sort of controller connection. With typical track wiring this allows a lower current fuse, but only protects against that problem and doesn't provide any protection for shorts on the track.

Tracks that use a 3 pin plug to connect the controller generally don't have this because the risk of that problem is very low. They often have a fuse in the power (+) supply line to the controller, this protects against shorts on the track and controllers wired up incorrectly.

With one power supply per lane, the power supply's current limiting / short circuit protection is often used.
 

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What type of short circuit and overcurrent protection do guys use when running with high current systems?
 

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novice jazz player &
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But a typical 40Amp power supply will happily deliver 40Amps regardless of whether it is powering lots of fast accelerating slotcars or gently kindling you favourite floor coverings. Ask it for 41Amps and it might start to show some slight concern.

To be clear I think we need to improve strategies for short circuit and over-current protection for our very high power dc systems.

c
 

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Prof I T
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Is 40a @12v the same 40 @ 230v..?
 

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novice jazz player &
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Is 40a @12v the same 40 @ 230v..?
Interesting question, in the UK a mains voltage consumer unit for a small house could be rated at 100A 240V and for a stand-alone consumer unit for a garage could typically be 40A 240V. In each case this would represent the maximum permissible current for all circuits supplied by the consumer unit in question. So the numbers are comparable to those quoted in the above question.

Meanwhile a 40A 12V slotcar power supply if 80% efficient would draw 2.5A from the mains at full load.

As I say, interesting question.

c
 

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Prof I T
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might be a good idea to look outside of the DC wireless only field , Analouge BRSCA tracks regularly use 40-50 amp power supply and that's per lane..

Also the Henley 24hrs event use similar from memory but obviously for the whole track..

So the answers to questions about circuit protection are probably already known
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novice jazz player &
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Great point... and of course the type of overload protection circuits built into the ARC PRO, APB and CU(D124/132) could be implemented in a scaled up version. This would certainly take us beyond reliance on the current limiters built into general purpose 12-15V high current PSUs such as the Fusion 600W... i.e. up 40A at up to 15V.

I am setting up a multicar high current test system - in my dev lab - and so am very interested in the instruction manuals and advice in this area from the main suppliers of dc wireless slotcar systems.

And of course all of this responds to the OP... (slightly rephrased as) what is the best power supply for this type of high current dc wireless slotcar system?

c
 
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