Power Shield X

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The Power Shield X series is a DCC Power Management device. The PSX will handle the increased inrush currents which occur due to large capacitors used for sound systems. This load appears as a system short circuit until the capacitors are charged. The logic in newer PSXs determines if the load is a true short or just an inrush overload.

The Power Shield X (PSX) is the continuation of the Power Shield series of power management devices.

Power Shield X (PSX)

There are several versions of the PSX:

  • PSX-AR, with integrated stall motor decoder
  • PSX-ARFB, with network feedback
  • PSX-ARSC, with integrated snap switch decoder
  • PSX-ARSCFB, with network feedback.
  • PSX-AR-AC, for 2 rail AC.

The PSX series also includes 4 DCC power district circuit breakers. They are identified as PSX-x, where the x indicates how many blocks they can control, from 1 to 4.


Compatible with 2 Rail AC.

  • Automatic Coordination of Auto Reverse and Circuit Breaker Tasks: It is both a auto reverser and a circuit breaker. Fast, all solid state design with reliable quiet electronic reversing, no blinks, clicks or sparks!
  • Adaptive Load Reset: Electronically senses if the overload is a real short or due to in-rush capacitance of sound decoders.
  • Automates Reverse Loop Turnouts: Integrated stall or solenoid decoder, automatically lines up turnouts when the polarity reverses. Switch machine can be controlled accessory commands or push buttons as well.
  • Manual or Automatic Reset
  • LEDs can be added to monitor; input/output power and status.
  • Trip currents adjustable by jumpers or CVs: 1.27 to 19.2 A
  • A single CV command sets all Addresses and CVs to original factory values.
  • An audible sounder can be added to the card to alert you when there is a short.
  • Low Current booster reset if needed
  • Auto Stop with CV Reset: A photocell can detect a train in the reverse section and turn off power. A DCC command can then restore the power
  • Board size: is 5 3/4 by 3 3/4 inches

The PSX-AR may not operate reliably when connected downstream of a PSX Circuit breaker.


All of the PSX-AR features plus

  • Feedback: Shorted and Occupancy Status to Digitrax (LocoNet), Lenz (XpressNet) and NCE (CabBus)
  • Block Occupancy Outputs: Indicates block is occupied or shorted
  • Occupancy Amps adjustable

All PSX series devices also include network feedback


There are some configuration details regarding the PSX-AR. Read the manual for the details


For use with Digitrax DCC systems, a jumper must be installed from terminals J7-3 to J7-4 (LocoNet Configuration). After doing that, move the program jumper to J3-1 and J3-2 (Programming Mode), an apply DCC power. When LED D6 stops flashing, remove DCC Power and return the jumper to J3-2 and J3-3 (Operations Mode).

Set the command station's OpSw 18 to CLOSED to extend the time before the booster's circuit protection activates. The PSX-AR will still have settings to configure to select its trip current either via CV49 or jumpers.


For NCE there are two options. Choose 1 or 2:

  1. Install a jumper from J6-1 to J6-2
  2. set CV49 = 1

Do not do both steps. Only a single option is needed.

Analog Operations

The PSX-AR will not work when Analog mode is in use.

Rail Gaps

Gaps are required for the PSX and PSX-AR to function. It is recommended to offset one gap by 19mm from the other rail's gap. Fill the gap to prevent it from closing.

Additional programming may be require if a locomotive hesitates when crossing a reverse gap.

PSX-AR Accessory Addressing

  • If using a Digitrax system see the note above.

The PSX-AR has three accessory addresses in use:

  1. Turn output On or Off
  2. Activate the photo cell detector
  3. Throw a switch

The manual has complete instructions, including any variations necessary for various DCC systems.

Options with the PSX-AR

See the manual for complete details.

Reverse Loops

It is possible to use pushbuttons to throw a switch at the entrance to a reverse loop. The wiring is quite simple. Pressing a switch will throw the turnout and reverse the phasing of the rails at the same time.

Track Status Indicators

A simple circuit consisting of two diodes, two LEDs, and two resistors can be created to indicate phase settings on a track schematic or other display.


The DCC Specialties Website has a lot of information and more DCC items as well. Main Website
PSX Manual
PSX User Shares Layout Information
Controlling Hidden Staging with the PSX Series Power Sheild X Hints and Tips