Azatrax PFRR-3W User manual

Installation guide, 'Pickle Fork' Back-and-Forth Model Train Controller Azatrax model PFRR- W
This controller can automate a 'back-and-forth' model train layout
with optional siding at either or both ends of the layout -- or, one
train can travel continuously around a loop, making stops at
predetermined locations.
Requirements:
Trains must be DC powered, not DCC or AC, because train
direction is controlled by the polarity of the track power.
aximum track current: 2 amps (2.5 amps for acceleration).
If turnouts (track switches) are used, the turnouts must be operated
by switch machines with 3-wire control cables. These are 'snap'
type switch machines with twin coils such as Atlas, Bachmann or
Peco.
If your turnouts have switch machines with 2-wire control cables,
use the Azatrax PFRR-2W control circuit.
An accessory power supply, 12 to 17 volts AC or DC is required to run the PFRR circuit. This is separate from the track
power.
This power supply must have sufficient current capacity to operate the switch machines -- typically 2 amps or more.
Train sensors:
One train sensor must be installed at each track location where a train is to stop. One sensor is needed at each track end
point. Additional sensors or external detectors may be added for station stops where a train will momentarily stop, then
continue in the same direction.
The PFRR controller has connections for up to four train sensors. They are numbered W1, W2, E1 and E2.
The operating mode of the PFRR is determined by the combination of sensors that are connected.
So be careful to connect your sensors to the correct terminals on the PFRR controller. The wrong
combination will result in unexpected operation.
Back and forth, no turnouts
Connect sensors: Do not connect W2
W1 at west end
E1 at east end
2 may be used as a station stop between W1 & 1.
xternal detectors may also be used for station stops.
see
page
2
Back and forth, one turnout
Connect sensors: Do not connect E2
W1 at west end, track 1
W2 at west end, track 2
E1 at east end
Use external detectors for station stops if desired.
see
page
2
Back and forth, two turnouts
Connect sensors:
W1 at west end, track 1
W2 at west end, track 2
E1 at east end, track 1
E2 at east end, track 2
Use external detectors for station stops if desired.
see
page
2
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Connect sensors: Do not connect E1
W1 at exit from clockwise loop
W2 at exit from counter-clockwise loop
E2 at east end
Use external detectors for station stops if desired.
see
page
Connect sensors: Do not connect E1
Do not connect E2
W1 at first station stop
W2 at second station stop, if desired
xternal detectors may also be used for station stops.
see
page
Back-and-forth operation Must connect sensors W1 and E1
Sensors W2 and E2 are optional
Step 1 - Track wiring and rail gaps
Connect the main line rails to terminals 'main N' and
'main S' on the PFRR circuit board.
Power-routing switches are track switches that
automatically connect power to the track that is
aligned with the switch points, and cut off power to
the other track. If using power-routing switches (or
no switches) then no insulating rail gaps are needed.
Power only needs to be connected to the main track.
If your switches are not
the power-routing type,
one rail of each siding
must be electrically
isolated from the rest of
the track. This is done
with a plastic rail joiner
or by cutting a gap in the
rail. It is important to put the gaps or plastic joiners in the correct rails.
Non-power-routing switches also need feed wires connected from the PFRR 'sidings' terminals to the siding rails as shown.
Use the above wiring diagrams when non-power-routing track switches are being used.
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Step 2 - Install the Sensors
Install a train sensor at each location where a train will stop. Leave space
between the sensor and the end of the track so the train will be able to slow
down and stop before reaching the end of the track. The rate of deceleration
and acceleration is varied by turning the ACCEL adjustment.
Sensors W1 and E1 must always be used for back-and-forth operation.
Add sensor W2 for a siding at the west end, and sensor E2 for a siding at the
east end.
For the basic configuration only - sensor E2 may be installed for an
intermediate station stop between sensors W1 & E1.
Other station stops can be created with external train detectors connected to terminals 'ST' and 'C.'
Go to page 4 for sensor installation details.
Out-and-back reverse loop operation Must connect sensors W1, W2 and E2
Do not connect sensor E1
Step 1 - Track wiring and rail gaps
Connect the loop track outside rail to
'main N' on the PFRR circuit board.
Connect the inside rail to 'main S'.
Connect the 'north' rail of the tail
track to siding terminals E2N and
E1S. Use a short wire to connect
E2N to E1S.
Similarly, connect the 'south' rail of the tail track to siding terminals W2N and W1S.
Install insulated rail joiners or cut insulating gaps in all four rails where the loop ends meet the turnout.
Step 2 - Install the Sensors
Install train sensors at the locations shown above. Leave space between the sensor and the end of the tail track so the train
will be able to slow down and stop before reaching the end. The rate of deceleration and acceleration is varied by turning
the ACCEL adjustment.
Station stops can be created with external train detectors connected to terminals 'ST' and 'C.'
Go to page 4 for sensor installation details.
One-way loop operation Connect sensors W1 and/or W2
Do not connect sensor E1 and do not connect sensor E2
Step 1 - Track wiring and rail gaps
Connect one loop track rail to 'main N' on the PFRR circuit board.
Connect the other rail to 'main S'. To run the train in the opposite
direction, swap these two wires.
Step 2 - Install the sensors for station stops
Install train sensor W1 where the train will stop momentarily, then
continue in the same direction. If a second stop location is desired,
install sensor W2.
Additional station stops can be created with external train detectors connected to terminals 'ST' and 'C.'
The rate of deceleration and acceleration is varied by turning the ACCEL adjustment.
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Installing the Sensors
An IR (infrared) LED paired with an IR receiver may be used at each sensor location, or a mechanical switch such as a
magnetic reed switch may be used. When using a mechanical switch, a resistor must be wired in parallel with it (see pg. 5).
Use a resistor of 200 to 1000 ohms.
Each IR sensor pair may be installed in one of two different ways - 'Across the Track' or 'Reflective.'
Across the Trac sensing: The IR LED is positioned horizontally on one side of the track, and its
IR receiver is placed on the opposite side. A train is detected when it blocks the light path between
the IR LED and its receiver. The distance between the IR LED and receiver can be up to 18 in.
(46cm), or more with careful alignment. Place the sensors at an angle across the track to prevent
the sensors being fooled by the gap between cars.
Tip #1 - If mounting the sensors vertically as shown here, slide the plastic tube away from the sensor then carefully bend the
leads to a right angle. The leads are somewhat brittle, bending them more than two or three times may cause a break.
Tip #2 - Locate the IR receiver so it faces away from bright lights or sunny windows. Use scenery or structures to conceal
the sensors.
Reflective sensing: Trains are detected when light from the IR LED is
reflected off a train and sensed by the IR receiver. Typically the sensors
are mounted in two #12 (3/16 inch, 4.8mm) holes drilled in the roadbed
as shown above. Vertical installation works for S, O and larger scales as
long as there is no structure above the track such as a bridge.
Angling the IR LED and its receiver toward each other is best for N and HO scale where the trains are close to the rail head,
and in places where an object above the track might cause false detections. Angle the IR LED and receiver so their
centerlines intersect at the height of the bottom of your rolling stock.
Tip #3 - Track can be ballasted after sensors are installed. Cover sensors with transparent tape. Apply ballast. When the
glue has dried remove ballast from the sensors with a dental pick or similar tool. An opening of just 1 or 2 mm is required.
Connecting wires to the terminal bloc s: The PFRR has 'spring cage' terminal blocks for the IR sensors. Connections are
made as follows:
♣ Strip 3/8 inch (1 cm) of insulation off the end of the wire.
♣ Use a small screwdriver to push down (push, do not turn) the terminal's button. Push firmly.
♣ While the button is pushed in, hold the wire at a 45 degree angle to the terminal block and push it in. About 3/8 inch of
wire should go into the terminal block.
♣ Release the button. Tug on the wire to make sure it is secure.
Note - not all track configurations require installation of all four sensor pairs.
Connecting a sensor pair: This example shows the W1 sensor pair. All IR sensors connect to the PFRR in a similar way.
Connect the orange (or red) wire from the IR LED to the K terminal (W1K in this case).
Connect the green (or blue) wire from the IR receiver to the F terminal (W1F in this case).
Now, how you connect the white and yellow wires to the PFRR will determine whether this sensor pair operates in 'Across
the Track' or 'Reflective' mode. See the diagrams below.
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Add connections for the next sensor pair: This example uses sensor pair W2, your installation may not use sensor pair
W2. Connect the orange (or red) wire from the IR LED to terminal W2K. Connect the green (or blue) wire from the IR
receiver to terminal W2F. As with sensor pair W1, how you connect the two white and yellow wires will determine whether
sensor pair W2 operates in 'Across the Track' or 'Reflective' mode.
Sensor pair W2 can operate in the same mode as W1, or in a different mode. When both sensor pairs are wired to the PFRR,
there will be two white or yellow wires in 'X' and two white or yellow wires in 'R.' For best reliability, twist the ends of
these wires together.
Additional wire may be spliced to the sensor leads if needed. Use similar twisted pair wire up to 26 ft (8m).
Connect any remaining sensors. The E1 sensor, if used, connects to terminals E1K, E1F, X and R similar to sensor W1.
The E2 sensor, if used, connects to terminals E2K, E2F, X and R similar to sensor W2.
➽ Pairing is important! The IR LED that is connected to W1K must be paired on the layout with the IR receiver that is
connected to W1F. Likewise the IR LED that is connected to E1K must be paired on the layout with the IR receiver that is
connected to E1F. This is true for all sensor pairs.
Mechanical switches: Reed switches, limit switches or relays (such as
Azatrax RD1 detectors) may be used in place of the IR sensor pairs.
Connect the two leads of the normally open switch or relay contact to
the X and K terminals for the appropriate sensor. A resistor must be
connected in parallel with the detector switch. Use 200 to 1000 ohms.
Test the sensors:
Connect an accessory power supply, 12 - 17 volts AC or DC, to terminals P1 and P2.
If one side of the power supply is connected to a layout 'common' or 'ground,'
connect it to terminal P2. Connect the 'hot' side to P1.
When power is first turned on, the red & green Direction LEDs will flash back and forth (except for the Continuous Loop
mode, only the red W LED will flash because the train only goes in the 'west' direction).
During this time the yellow Detector LEDs will light to show which detector inputs actually have IR sensors or
switches/resistors connected.
Verify that all the detectors you intend to use show a lighted LED.
Now check each detector individually by placing a rail car or other solid object on the track at each detector location. The
yellow LED for each detector on the PFRR circuit should light when an object is at the detector, and should go out or blink
when the object is removed.
Step - Connect Optional Switch Machines
If the east end has a track switch, connect the east switch machine to
PFRR terminals EM1, EM2 and EM3.
If the west end has a track switch, connect the west switch machine to
PFRR terminals WM1, WM2 and WM3.
For an out-and-back reverse loop, connect the switch machine to terminals WM1, WM2
and WM3.
Do not connect to other buttons or circuits.
Do not connect 'E2' or 'W2' to a layout 'common' or 'ground.'
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Test the switch machines:
Bac -and-forth, end-to-end configurations:
Place an object like a rail car at all end point detector locations (E1, W1, E2, W2) that are being used.
The direction LEDs will flash in unison to indicate that too many trains are being detected. The track
switches will all align to track 1.
Out-and-bac reverse loop configuration:
Place an object like a rail car at detector locations W1 and W2. The direction LEDs will flash in unison and the turnout will
align toward sensor W1 (a train departing the tail track will go to the right, for a counter-clockwise trip around the loop).
Tip #4 - If a switch aligns in the wrong direction, swap the W 1/W 3 (or E 1/E 3) wires to the switch machine.
Always turn off power before making or changing connections !
When the switches are working properly, turn off power to the PFRR and remove the cars / objects from the sensors.
Step 4 - Connect the Train Power Supply to terminals T+ and T-.
Begin with the 'ACCEL' adjustment turned counter-clockwise for quick acceleration and
braking.
Place a train on the track. Set the speed knob to a slow setting, then turn on the train power. The train will not move until
the PFRR controller has been turned on (power applied to P1 & P2).
Increase the speed control until the train moves. If the train will not move, change the polarity of the power pack by
changing the direction control switch or swapping the wires at 'T+' and 'T-.'
ake sure the train moves East or West as the PFRR direction LEDs indicate. If the train is moving in the wrong direction,
swap the track power wires.
Tip #5 - Once the train is moving in the proper direction, mark the power pack's direction switch .
When the PFRR's power is first turned on, it checks the detectors to determine where trains are located. It also remembers
the switch positions from the last operating session. The PFRR uses this information to decide which train to run first.
ACCEL adjustment - Turn the 'ACCEL' adjustment clockwise for longer train acceleration and braking times. Turn it
counter-clockwise for quicker starts and stops. It is OK to let the train coast past the train detectors. The PFRR will
remember that a train passed the detector, and will assume the train remains on that end track until the train trips the detector
again when going in the opposite direction.
Memory Effect - The PFRR remembers when a train enters an end siding (see 'ACCEL adjustment' above), even if the train
passes the detector before it stops.
Why is the yellow LED blin ing? When a train enters an end track, it starts decelerating when it is detected by
that track's sensor. If the train coasts past the sensor before coming to a stop, the PFRR circuit remembers that a
train is on that track. A blinking yellow LED tells you the PFRR believes there is a train on that end track, but the
sensor is not detecting the train. This is a "hidden" train.
When the PFRR wants to bring that "hidden" train back to the main line, it applies power to the track and waits for that end
sensor to be tripped, indicating that the train is coming out of the end track.
If that end sensor is not tripped within 10 seconds, the PFRR assumes that train was manually removed. It will shut off track
power and mark that end track as empty. The LED will stop blinking. Then the PFRR will look for another train to move.
When adding a new train to the layout, make sure all trains are on end detectors before turning the PFRR on again. The
PFRR will take a few extra seconds to reconcile train locations before starting operation.
At least one turnout should be aligned with an occupied track when manually placing or removing trains from the layout.
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If the PFRR is turned on and it finds its turnouts are all aligned with empty end tracks, it assumes a train is somewhere on
the main line. It applies track power and waits for a train to arrive at one of the empty end tracks.
When removing a train from the layout, it is best to let the train run to an end detector before removing it.
If a train is removed from the main line, allow the PFRR several extra seconds to adjust to the new situation. If it is not
able to start correct operation then the PFRR memory must be cleared.
Clearing PFRR Memory - If you have manually moved trains on the layout and the PFRR seems unable to sort out the new
situation, you can reset the PFRR's memory by turning off the PFRR's accessory power. This clears the memory of all
"hidden" trains (see Blinking Yellow LED above). ake sure each train is on a detector. Place a temporary object (rail car,
paper cup, etc.) on all remaining end detectors. Turn on accessory power. Wait for the direction LEDs to flash in unison and
the switches to align with Track 1. Turn off power, remove the temporary objects from the detectors, and turn on power
again.
Station Stops - Additional train detectors may be added to create intermediate stopping points. When a train reaches one of
these detectors, the PFRR will stop the train for several seconds, then the train will continue in the same direction. The east
or west direction LED on the PFRR module will flash while the train is stopped.
These detectors may be separate circuits or switches. The example here
shows two station stops. One is implemented with an Azatrax RD1-NV
detector circuit, the other with a reed switch.
Connect each station stop detector to PFRR terminals ST and C. Unlike
mechanical switches used at the endpoints (E1, E2, W1 and W2), the
switches used as station detectors do not need a resistor connected to them.
Longer Delays - The default pause time is six seconds. This can be changed to 12 seconds
by connecting a wire from terminal DL to C.
For other delay times connect a resistor or a 10k potentiometer to terminals DL and C.
A 10k resistor results in the maximum pause time of 45 seconds.
1k ➙ 4 sec, 3k ➙ 8 sec, 6k ➙ 20 sec, 10k ➙ 45 sec. (Times are approximate.)
On the first pass after the PFRR has been turned on, the train will only stop for one second at
each station stop. This lets you check all stops without having to wait for the full delay at each stop.
Troubleshooting - If the train is not moving, check the PFRR LEDs. If either the east or west direction LED is on steadily,
this indicates that power from the power pack is being routed to the rails. Check that the power pack is turned on and the
speed control is turned up. Check the power pack's direction switch.
Check for dirty track or a wiring problem between the power pack and PFRR or between the PFRR and the track.
If one of the direction LEDs is flashing and the other is off, the PFRR has sensed a train at a station stop detector. The
PFRR will pause the train and flash the direction LED, then will resume. When the train pauses at the west or east end, both
east and west direction LEDs will be off until the train starts in the reverse direction.
If the train is not moving and both direction LEDs are flashing simultaneously, it is because the PFRR senses too many
occupied detectors and there is no open destination for the train. Check sensor adjustments. The PFRR's memory may need
to be cleared if it is unable to resume normal operation (see above).
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