Update on the testing of the auto reverse units.

The MRC AD520 and the DCC Specialties Frog-AR are powered by the track buss in the same power block as the mainline buss that is connected to the reverse loop.  I use a DCC Specialties PSX as the circuit breaker on the mainline.


1.  MRC AD520 - $33.81 at Blue Ridge Hobbies

Very easy to set up.  Two red wires to the mainline and two yellow wires to the reversing section.  No options or adjustments to set.
Wires are approximately 22 AWG and do not have connectors.  The wires need to be stripped and spliced to the mainline and reverse loop busses.

Results of test:  Worked initially but became intermittent.  Several retests with the same results.  I plan to retest again.


2.  DCC Specialties Frog-AR - $49.95 at Tony's Train Exchange

Can be configured to power four turnout frogs, or two turnout frogs and one reverse loop or two reverse loops.  Has adjustable trip current independent of the circuit breaker for the block it is in.

Requires wire jumpers soldered to the pc board to configure for reverse loops.  Also requires wire jumpers soldered to the pc board to change trip current from one amp to up to four amps.
Must be used within the same block powering the mainline and frogs or reverse loops.  Input power is off the mainline buss.

Screw down terminals for input power from mainline block and four screw down terminals for wiring to frogs and / or reverse loops.  One wire for each frog and two wires required for each reverse loop. 

Worked well without stalling or hesitation.  Ran a two diesel consist into and out of reverse loop and also had another diesel enter reverse loop while first consist was in loop without any stalling or hesitation.



3.  DCC Specialties PSX-AR - I had these sitting on the shelf since 2013.
Current cost is $53.95 at Tony's Train Exchange


This is a combination circuit breaker and auto reverser.  Set up is similar to the standard PSX with push pin jumpers to set trip current at one of four settings - 1.27, 3.81, 6.35 or 8.81 amps.  Screw down terminals for input power from booster and for output terminals for reverse loop.

Test results the same as the Frog-AR.

I plan to use this device to power Fuhgeddaboudit Yard (upper level yard) which is a large multitrack reverse loop incorporating a freight classification yard and locomotive servicing area.

This device has many features that I will not use so it is overkill for this application.  In testing I found that 3.81 amp trip current setting will handle five sound equipped locomotives at startup.  Since this is a yard there may be that many powering up although I plan to use the switches within the turnout motors to control on / off power to various tracks limiting the number of locos in the servicing area firing up simultaneously.  The classification yard will always be powered.