PSX-ARSC bewilderment

[Drumguy]

Hi!

I am adding a PSX-ARSCFB to auto-throw a turnout that enters/exits a reverse loop. I'm a bit dense when it comes to figuring out some things, but darn good at following simple instructions. The PSX manual is a bit obtuse to my limited knowledge of electronics. The reversing bit is easy enough, but I have 2 questions:

1) I'm using it to control an Atlas twin coil machine. PSX manual says to connect one coil to J9-1, and the other to J9-3. It says J9-2 and J9-4 are the positive output voltage. On the surface this seems 2 or 4 should obviously be the machine's black (common) wire. However, I've read somewhere that Digitrax uses a negative common. So I am a bit usure what goes where…

2) This board is replacing a digitrax AR1, which was wired downstream from one leg of a PM42. Curious if I can wire the PSX in its place -- still downstream of the PM42. I realize this renders one leg of the PM42 redundant, but I've got 2 PM42's and only need 6 subdistricts, so no big deal. Wiring it downstream just makes it an easy replacement, no new wiring (except the auto throw wires). And if I understand correctly, the PSX will trip long before the PM42 does, allowing that leg of the PM42 to pass everything through itself unawares.

I realize there are easier ways to auto throw a turnout, but the location won't fit a tortoise, and due to a few other planning errors--and the misguided assumption that twin coils make things easier than tortoises--lets just say that ship has sailed.

[rrinker]

 Any DCC common has nothing to do with switch machines controlled by another option - but commons are typically the - side except in one notable exception - the blue common wire in a DCC decoder is the + side of the circuit. Atlas twin coil switch machines are just that - coils - so they don;t really have a polarity. They are designed to work on AC, so it matter not one bit which side goes to the common terminal of the machine and which goes to the two coil wires. There is I assume some setting to be made on the PSX-AR if it supports twin coil machines because for a Tortoise the power is left on constantly, this would burn out a twin coil, which needs only a momentary pulse of power. I didn;t think you could use a twin coil machine witht he PSX-AR, but I haven't read the instructions lately.

Downstream of the PM42 is fine. What doesn;t work is the opposite mix of brands - an AR1 downstream of a PSX breaker. The PSX always trips before the AR1 and can't be adjusted. But the PSX-AR downstream of the PM42 will be fine. It IS redundant, but if you can't easily run a new bus wire from in front of the PM42 to the reverse loop area, it will work.

               --Randy

 

 

[Drumguy]

Thanks, Randy. I assumed the twin coil connections were as you describe, but I prefer to double check my assumptions rather than risk fire, explosions, and catastrophic mayhem in general!

There are 4 diferent PSX-AR boards now, and two of them are factory set up for solenoid machines. I ran some tests last night, and the PM42 leg did trip twice (odd). So I'll just do a bit of re-wiring and bypass the PM42 for this subdistrict, keep it simple.

[DigitalGriffin]

increase the trip current on the pm42 or decrease it on psxar or do both