Powering Powered Up hub from 9v track?

[Modeltrainman]

With the news that FX Bricks cables are coming, does the possibility exist of powering an unmodded Powered Up from my 9v track? Ideally,I'd like to leave everything unmodified, and plug in a cable. Could that be possible, if not yet?

[Toastie]

28 minutes ago, Modeltrainman said:

With the news that FX Bricks cables are coming, does the possibility exist of powering an unmodded Powered Up from my 9v track? Ideally,I'd like to leave everything unmodified, and plug in a cable. Could that be possible, if not yet?

Yes. Plugging in maybe difficult, though, as the PUp hub wants 6 x 1.5V batteries. And “upstream” of the PUp hub's power feed, some additional gear is required, at least this is my experience, others may know better. You may want to take a look at this pinned topic:

The PUp hub likes nicely conditioned 7 … 9V, as, e.g., provided by rechargeable or alkaline batteries. The “condition” of 9V track power depends on a) your track power supply and b) your power pickups. What I have done (there are several posts here on EB, I am happy to digging them up, let me know) - and this is the most expensive, but really fail-safe approach:

1. Power pickup = burnt or modified 9V train motor. The nice things about this is that the wheels are usually in good contact with the rails, as they are sort of “spring-loaded”. I strongly recommend putting in a bridge rectifier to avoid any polarity issues.
2. Power supply = the rechargeable PowerFunctions battery box 8878. If you are not afraid of the dark side, they sell for $10. If you are, you are looking at +$80.
3. You feed the power pickup terminal to the charging socket of 8878. The latter accepts any voltage between <9V and 18V; even if the power feed from the rails is noisy - 8878 simply does not care.
4. You feed the PF 9V output terminal to the PUp hub with a custom cable you have to fabricate.

As a result, your train can run “forever” provided it is always on 9V track; can run over plastic track, as the battery box then still feeds the PUp hub; and simply parking it on 9V track will fill up the battery box to full, when not in use.

As said, there are some references, let me know if you need these.

All the best
Thorsten

Edited yesterday at 08:11 PM by Toastie

[Modeltrainman]

2 minutes ago, Toastie said:

Yes. Plugging in maybe difficult, though, as the PUp hub wants 6 x 1.5V batteries. And “upstream” of the PUp hub's power feed, some additional gear is required, at least this is my experience, others may know better. You may want to take a look at this pinned topic:

The PUp hub likes nicely conditioned 7 … 9V, as, e.g., provided by rechargeable or alkaline batteries. The “condition” of 9V track power depends on a) your track power supply and b) your power pickups. What I have done (there are several posts here on EB, I am happy to digging them up, let me know) - and this is the most expensive, but really fail-safe approach:

1. Power pickup = burnt or modified 9V train motor. The nice things about this is that the wheels are usually in good contact with the rails, as they are sort of “spring-loaded”. I strongly recommend putting in a bridge rectifier to avoid any polarity issues.
2. Power supply = the rechargeable PowerFunctions battery box 8878. If you are not afraid of the dark side, they sell for $10. If you are, you are looking at +$80.
3. You feed the power pickup terminal to the charging socket of 8878. The latter accepts any voltage between <9V and 18V; even if the power feed from the rails is noisy - 8878 simply does not care.
4. You feed the PF 9V output terminal to the PUp hub with a custom cable you have to fabricate.

As a result, your train can run “forever” provided it is always on 9V track; can run over plastic track, as the battery box then still feeds the PUp hub; and simply parking it on 9V track will fill up the battery box to full, when not in use.

As said, there are some references, let me know if you need these.

All the best
Thorsten

I'm sorry, sir, I didn't understand any of that, save for the implied 'It's possible, but...' I'm sorry if I didn't phrase it better. Basically, 'once FXBricks stuff comes out, can I plug a powered Up to 9V cable to their wheelset, other end into the A port on a PU hub and power the hub via track?' is my question.

[XG BC]

no you cannot, since you cant input power into the hub via that port. thats only a power output. it still wont be that simple.

either go wheelset -> powerfunctions rechargable battery box -> powered up hub battery compartment.

or go wheelset -> big capacitor and powered up hub (the capacitor is just to make the track power more stable, you might not even need it)

[dr_spock]

You could power the PU train motor off the 9V tracks.  You would need a power pick up wheel set.  Connect the PU train motor cable to the pickup.  If you make your own female PU adapter, pin 1 & 2 are the power control lines.

Powering the PU hub off the 9V track could be done.  You would still need a power pick up wheel set.  You can not plug into the A port.  You would need an adapter to take the place of the batteries holder.  Probably have to set the 9V train controller to full 9V output. Also you'll need the +/-  polarity to be correct or have some fancy diode bridge.

[XG BC]

by diode bridge you mean a bridge rectifier. these are available in one package, preassembled, you just need to connect the ~ inputs to the wheelset and the + and - output to your hub.

something like this:

https://www.digikey.com/en/products/detail/vishay-general-semiconductor-diodes-division/W04G-E4-51/754892

[Modeltrainman]

Thank you, all! Hopefully, someone could invent a way as ditching batteries, but still using the Hub'd be great!

[dr_spock]

Something like this could be 3D printed to make an adapter to feed 9V track power to the PU hub if you don't want to solder wires directly to the PU hub circuit board.

https://www.thingiverse.com/thing:6858192

[Modeltrainman]

Sadly, no 3D printer. I wish we knew why LEGO decided electricity was bad. Traditional model railroading has DCC.

[XG BC]

it was too expensive to make, and lego was struggling financially at that time. all plastic was cheaper to make, and thus here we are. i dont like it either (hence why i still use 9v with custom power pickups and copper tape on plastic track)

[L-Gauger]

@Modeltrainman, you make an interesting point regarding conventional model railroad power sources compared to Lego train power sources. As someone who is active with both conventional (HO and N scale) trains and Lego trains, I've never fully (notice I did say fully) understood why the battery-powered solutions offered by Lego are disliked by so many in the Lego train hobby. It's true that conventional model railroads usually use track power, but for the last eight years or so battery-powered, remote-controlled trains have been heralded by conventional model railroaders as the wave of the future. Meanwhile, us Lego train fans have had battery power since the mid-2000s, but many complain and wish for the days of track power. I can't deny the advantages of track power, but I also know what a pain it is to keep the track clean on my N and HO scale layouts. I relish my L gauge trains because, even though they do require battery changes, spotty electrical pickup is never an issue. 

That's not to say battery power is the only way (obviously it isn't, and Lego makes their battery boxes way too big to fit in little switchers/shunters,) but I do think that we Lego model railroaders should count our blessings in that we have both battery power (from Lego and 3rd party) and track power (from old 12v, 9v, and Fx Track/Fx Power.) Traditional model railroaders have to build their battery systems from scratch, and I'm grateful we don't have to. 

[XG BC]

30 minutes ago, L-Gauger said:

As someone who is active with both conventional (HO and N scale) trains and Lego trains, I've never fully (notice I did say fully) understood why the battery-powered solutions offered by Lego are disliked by so many in the Lego train hobby. 

I personally dislike it because batteries need to be changed, charged etc, and take up space (although with cirquitcubes the space thing is kind of a moot point, atleast for normal gauge models). track power is just more flexible with models, especially if you use custom pickups from model railroad companies like märklin.

regarding contact: lenz has an awesome solution if you use DCC. i currently dont, but my dad does, he is into h0 scale model trains, he has an h0 scale model köf II from that company. It has a supercap that powers the decoder through dead spots while still remaining controllable (i guess through capacitive coupling). its super wild, here is a Video (not my dad):

it can literally drive over a piece of paper and keep going. of course this is more involved than just plugging a hub in and stuff, but its still incredibly cool.