Protip: If your loconet is acting stupid, add more power.

[Ed Kapuscinski]

On a larger layout, it's folly to rely on track power (Rail A / B) to power those devices alone.  I make it a practice to use PS14s or equivalent to power all the electronics on the layout, including UPs

Yup. I thought I could get away with "every other thing". Nope.

[Ed Kapuscinski]

Oh, BTW, here was my "tell" yesterday. The throttle was stuck at this screen when I plugged it in.

[ Guests cannot view attachments ]

[reinhardtjh]

Oh, BTW, here was my "tell" yesterday. The throttle was stuck at this screen when I plugged it in.

(Attachment Link)

That's interesting.  Usually when the Loconet craps out it's down around 9v.  13.1v is actually a good voltage.

And yeah, when I read "optional" I figured that because the throttle jack next to it was powered it'd be ok. It was for something like six months. But then this past week: noooope.

All it takes is to have a throttle with a dead or low battery plugged in...  *boom*  Ask how I know.   

Ed specifically stated "LocoNet acting stupid".
Is LocoNet the bus for throttles or other similar devices? It also supplies power to the devices on that bus?  Just to verify my understanding of how Digitrax DCC works.

Peteski, LocoNet is a control bus/network.  It can provide power to devices plugged into the bus - generally throttles plugged into the LocoNet faceplates.  But as others have remarked, it's a road with potholes.  The LocoNet faceplates have power jacks that can be used to provide power to devices plugged into them and that generally the smart thing to do.  The LocoNet can power a few devices but if the voltage gets dragged too low then "bad" things happen.  Not quite crossing the streams bad, but close enough.

[mmagliaro]

That's interesting.  Usually when the Loconet craps out it's down around 9v.  13.1v is actually a good voltage.

All it takes is to have a throttle with a dead or low battery plugged in...  *boom*  Ask how I know.   

Peteski, LocoNet is a control bus/network.  It can provide power to devices plugged into the bus - generally throttles plugged into the LocoNet faceplates.  But as others have remarked, it's a road with potholes.  The LocoNet faceplates have power jacks that can be used to provide power to devices plugged into them and that generally the smart thing to do.  The LocoNet can power a few devices but if the voltage gets dragged too low then "bad" things happen.  Not quite crossing the streams bad, but close enough.

This is the part I wasn't clear on.  It looks like the faceplates (which means any throttles you plug in) will get powered off the LocoNet pins 1/6 if you don't have auxiliary power.  But the BXP88 looked like it was getting powered off the DCC rail power, so it should not be dragging down the LocoNet supply.  In fact, I would have thought that when Ed turn on the rail power, things would have gotten better, not worse, because the BXP88 would no longer run off the LocoNet bus power.  So is that not what it does?  Is that BXP88 running off the LocoNet unless you plug in an auxiliary power supply?

In retrospect, while I understand that they were trying to make this simple for people with small layouts (i.e. just plug everything in and it works), it was a really bad idea to power ANYTHING off the actual network lines (LocoNet).  That's like trying to run my Ethernet router off the CAT-5 cable plugged into it.

[reinhardtjh]

This is the part I wasn't clear on.  It looks like the faceplates (which means any throttles you plug in) will get powered off the LocoNet pins 1/6 if you don't have auxiliary power.

Correct. There is a diode power splitter setup using the LocoNet or the aux power jack - whichever is higher voltage wins.

But the BXP88 looked like it was getting powered off the DCC rail power, so it should not be dragging down the LocoNet supply.  In fact, I would have thought that when Ed turn on the rail power, things would have gotten better, not worse, because the BXP88 would no longer run off the LocoNet bus power.  So is that not what it does?  Is that BXP88 running off the LocoNet unless you plug in an auxiliary power supply?

Digitrax is bad about disclosing the internal wiring of it's devices, but I'd wager that the electronics portion of the BXP88 is the same as the LocoNet faceplates.  That is, it either takes power from the LocoNet or from the aux power jack if used.  The connections for the Rail A/B are used for the detection circuits but probably just monitored for power flow and not used for operating the device.  Which would leave the BXP88 vulnerable to a bogged down LocoNet

In retrospect, while I understand that they were trying to make this simple for people with small layouts (i.e. just plug everything in and it works), it was a really bad idea to power ANYTHING off the actual network lines (LocoNet).  That's like trying to run my Ethernet router off the CAT-5 cable plugged into it.

Well, there is POE but usually the power is supplied by the router, not vice-versa.

[nstars]

Be careful, in a way there are two different Loconet. Loconet has two signals on the pins. The genuine Loconet signal is on pins 3 and 4. Pins 2 and 5 are ground. The pins 1 and 6 are the tricky ones. The signal from the command station is the rail sync. This signal can only handle 125 ma. When connected to the back of UP’s the rail sync is passed through, but at the front the signal on the pins 1 and 6 is replaced by a 12 v signal when a power source is available. This signal can handle 500 ma. Please remember the rail sync is only necessary for items like boosters or detection units. Adding a power adapter to the Loconet just provides power to items like throttles.

Btw, the different Loconets is the reason why some European command station have a Loconet B connection (with rail sync) and a Loconet T connection (with 12v power)

Marc