Your Experien ce With PSX-1-AC ?

@Porschev posted:

Are you sure it won't pass the DCS signal?  I have 4 of them (4 loops) installed between the track and the TIU and the DCS signal on each loop works perfectly: 10/10.  I installed them after past  derailments killed a TIU. :-(    Does anybody know for a fact that there is a choke or filter in the PSX-1AC design that should be killing the DCS signal?

I believe they will pass the DCS signal, but as I recall some folks here were having problems with the PSX-ACs between the TIU and track. I'm thinking some could have added chokes? Been quite a while and I don't remember the exact outcome of the folks having problems?  My PSX-ACs are pretty old (9-10 years) and the discussions I recall were all some time ago as well.

As far as I know there are no filters or chokes on my older PSX-ACs.  I have no knowledge of this, but it's possible the PSX-ACs could have been updated to correct for the DCS signal interference?

I seem to recall there was a cap that was causing DCS issues on the PSX1-AC

I apologize if my information is dated about PSX and the DCS signal. Still, however, if the PSX is that much faster than the ph 180 breaker I can't see any advantage to having one after the TIU. It will protect just as well placed before the TIU I would think.

We have them on the club layout (thank you Adrian Tang), but DCS is run in "Passive Mode" and the PSX is only dealing with the AC current -- the DCS signal doesn't go through the breakers. Get it with the speaker -- it's annoying but lets you know immediately when there's a problem.

@gunrunnerjohn posted:

I seem to recall there was a cap that was causing DCS issues on the PSX1-AC

I see one larger 1000uf 25volt cap, possibly the suspect? The rest are all small SMT caps that I can't see any markings on. I count 6 that I can see, but the numbering seems to go up to C9 and there are 2 C8s.

I have four that I use to protect four districts on my layout.  They are hooked up after two legacy ZW-L's.  I run command only.  I added the sonic alarm and wired in a control panel overload led that activates when the alarm sounds.  These work great!

Well, good or rather EXCELLENT discussion. I am going ahead with the PSX-1AC on my 8 block railroad. I'll put them ahead of the TIU, between transformer and TIU. Until some brave soul does thorough testing to see if these degrade the DCS signal (and for that matter TMCC and legacy), I think the protection will have to be on "the wrong side of the tracks".

What a friggin hobby! My trains drag me into every corner of the known hobbyverse!

Don

@turkey_hollow_rr posted:

I apologize if my information is dated about PSX and the DCS signal. Still, however, if the PSX is that much faster than the ph 180 breaker I can't see any advantage to having one after the TIU. It will protect just as well placed before the TIU I would think.

I don’t see any way the PSX AC can be any faster than a 180 watt brick. This is for AC not DC. AC passes through zero 120 times a second. You can’t sense a short circuit when there is no current. Only as it approaches max voltage can it sense a change in current.
On a DC layout it can respond faster than 8 ms but not AC.

Folks using these after a modern transformer, they are really only useful if you want to limit the current on a section to less than ten amps which is what a modern higher power transformer of at least 180 watts trips at.

Want to turn your Post War ZW into a modern transformer? Use a PSX1-AC.

Pete

If there is a generous SME on the forum willing to take on such a study;  (pretty please! )  I suggest the study must answer at least these two questions:

1.) Which position offers the better protection for the TIU; between the track and the TIU or between the TIU and the Power Source.... and WHY?

2.) If installed between the track and the TIU, does the PSX-1AC degrade the DCS signal?  If so, can it be measured?   

I am running PH135 bricks.  In all cases the PSX-1AC trips first and without a visible spark/arc.  I have yet to have a PH135 breaker trip before or with the PSX-1AC.  Before I installed the PSX-1AC's it would take quite a short to trip the PH135 breakers and through the years I damaged 2 TIUs.  While it's only been a year, there has been NO damage to the TIUs since install of the PSX-1AC's.

@Porschev posted:

I am running PH135 bricks.  In all cases the PSX-1AC trips first and without a visible spark/arc.  I have yet to have a PH135 breaker trip before or with the PSX-1AC.  Before I installed the PSX-1AC's it would take quite a short to trip the PH135 breakers and through the years I damaged 2 TIUs.  While it's only been a year, there has been NO damage to the TIUs since install of the PSX-1AC's.

What are your PSXs set at? The bricks set point is fixed, the PSXs are adjustable.

Pete

Norton, I just don't trust Lionel's Chinese contractors to build the PH180s consistently as designed. Heck, when I set up my layout, 5 of the 12 PH180's were out of phase with the other 7!! If they can't get the doggone things in phase consistently (I mean--flip a coin!), what makes you so confident they are building the rest of that transformer to a superior standard?

The PSX-1AC is a cheap defense. We can discuss whether it's the first line or the second, but it's good insurance for me--saving just one loco repair repays the entire investment!

Don

Don, use what you want. Just trying to explain the physics here. As for anyone wanting to know if these degrade the DCS signal, just test it your yourself. See what the signal strength is with the breaker before the TIU then after the TIU. The handheld is your measuring device.

Pete

@Don Merz 070317 posted:

Norton, I just don't trust Lionel's Chinese contractors to build the PH180s consistently as designed.

But you trust the Chinese contractors that build the PSX1-AC boards?  I'm failing to see the distinction.

gunrunnerjohn...it's a very fine line...I was just put off by the phasing fiasco. Those are NEW transformers. I was expecting them all to be in phase (yes, I know--please pass the cheese to go with my whine...). But then too, I liked the sonalert addition to the PSX-1AC. That was actually what sold me on the thing.

The PSX-1AC does a good job of notifying me that there is a problem. It has lights, sounds and dancing girls--what more could you ask for? The PH180 just sits there and says "hah! good luck finding that short sucker!"

So yes, I like the PSX-1AC's Chinese contractors better... <grin>

Don

Don,

The PSX-1-AC can give you a better hint as to where a short is than a PH-180?  I may be wrong but I don't think so.

There are many ways a PSX-1-AC could be better but this isn't one of them.  (It doesn't say "crystal ball" in the features list.)

Mike

Good point!  My PSX-1AC's are set for 8 amps which probably explains why they trip before the PH135's.   Interesting that I don't get a nasty spark/arc with the PSX-1AC like I do with just the PH135.  Perhaps the PSX-1AC opening at lower amperage is the reason for no spark/arc?    I have tested the DCS signal on my layout and without the PSX-1AC (between track and TIU) and I can't determine a difference. 

The little spark I get with the PH180 actually is a good thing, it helps me find where things are touching the wrong rail.  If there wasn't any spark, it would be a lot harder to track down!

Do the PH135s have the same breaker circuit in them as do the PH180s?

GRJ, in the olden times, all the electronics (radio) guys used to be called Sparks. Since that usage is now gone, maybe you can adopt it for you and like-minded guys who have shorts to locate!

Don