Model Train Technology NANO PRECISION DETECTOR 2 User manual

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NANO PRECISION DETECTOR 2™
Between-the-rails
1mm precision up to 150mm
OPERATIONS MANUAL
Version 2.0a
Works with N, HO and O Scale

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There are sizes: Short and Long. Use a 9/32” twist drill bit to
drill a hole between the rails. We recommend you remove at
least one of the ties so that you are drilling through the
underlayment or roadbed and not through the plastic rails.

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INSTALLATION SUMMARY
Plug the Sensor cable into the Nano Controller on the right side
FIRST. This cable is a 5-Pin connector. This plug will NOT fit on
the left side 4-pin socket. In this way you cannot make a
mistake. The plug will fit only one way – smooth side up.
Plug the sensor into the 5-wire connector BEFORE turning the
power on – otherwise it will not start or calibrate.

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The Model Train Technology™ PRECISION DETECTOR™ – NANO
is designed to provide an adjustable, multifaceted, and precise
way to detect trains with the least amount of work to install
and operate. At last, there is no need to adjust or calibrate for
changing or difficult light conditions. The NANO sensor is small
enough to fit between the rails of N Scale track (or any scale
larger) and is tethered by a five-wire harness that connects to
the “brains” controller that you place under the layout.
After we had our share of frustration with IR (infrared)
detectors that use reflected light and are susceptible to
changes ambient light, particularly florescent, some LEDs and
mercury bulbs found at large train shows, we searched for a
smaller, faster, more precise technology that would also be
impervious to poor light conditions. The sensor we chose,
along with our software, will detect without regard to lighting
conditions.

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Summary of Features:
• 3 pre-set sensor distances for N, HO & O
• Precise sensor range (1mm up to 150mm)
• No more adjusting for varying light conditions.
• Auto-calibration mode for precise range setting
• Short range under track mean no false tripping
• Adjustable time-out (0-60 seconds)
• Reversable Signal output (INVERT)
• One Shot mode
• Includes a 2mm screwdriver.
The board should be powered with a 12VDC supply which is
what the MTT Power Module outputs. To make sure all the
detection works properly we designed a low-cost Power Center
Module that comes with a power supply.
To operate properly the Signal Controller or MTT Relay and
the NANO Precision Detector must be connected to the same
power source.

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On the board is a blue indicator LED. This will flash four times
when power is first turned on and thereafter will light when the
detector is triggered. (INVERT mode will have the light ON
when not triggered and OFF when triggered)
NOTE: If the Blue LED doesn’t not Flash four times rapidly at
power on, no amount of pressing the select button will help.
Either the cables are not connected properly, a pin is bend or
the unit is faulty. If the LED blinks continuously about 2 times a
second then the sensor is not connect or has a fault.
SENSOR HANDLING
The Sensor has three tiny openings that measure the distance
to an object. From our testing we found these to be reasonably
tolerant of dust that invariably will collect. Use a SOFT paint or
makeup brush to gently whisk away dust that collects.
Cover the sensor gently with a bit of blue painters’ tape
anytime you are using glues or spays in the vicinity.
For setup, press the SELECT button according to this chart:
The wires of the sensor are slightly twisted. You can reduce the
twist but do not “tighten” the twist.

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The wire length is about 9”. This is the MAX length where the
sensor will work properly. The signal in the wire is relatively
low power (weak) so it can be upset by electrical noise from
nearby wires. Try to keep the sensor wires away from other
wires and do not cross over wires is possible.
Immediate mode (No Timeout) is very fast and it available for
you to use. However, we strongly recommend you set the
timeout to 5 seconds (#6) to avoid “signal collision”. Setting
the value to a 5 second timeout makes the NANO extremely
reliable.
All you do is push the SELECT button to fit your scale and adjust
the location of the sensor to meet your specific needs.

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The detector can be also set to detect an adjustable Long
Range from 5mm up to 150mm. In this case, the sensor does
not have to be mounted under the track. You can use it
anywhere. Anything within the range you set beginning at
5mm - will trigger the detector.

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To use the LONG RANGE you will use the Auto-Calibrate mode
that you may be familiar with in our other Precision Detectors.
AUTO-CALIBRATE for LONG RANGE
1. Press and hold the select button on the sensor. The blue
light will turn on momentarily and then go off. KEEP
holding until the light comes back on.
2. When the light comes back on, RELEASE the button.
3. The LED will blink slowly 5 times, once per second, to
allow you time place a train car on the track in front of
the sensor you wish to calibrate.
4. After 10 seconds (5 blinks) there will be a 1 second pause
and then the LED will blink very rapidly for about 1
second. This rapid blinking is when the sensor Auto
Calibrates (measures) the detected train car distance.
That distance is saved in the memory of the sensor.
5. After the rapid flashing the sensor LED will go out for 2
seconds and then return to normal operating mode. The
LED should go back on since it now detects the rail car on
the track in front of it. Move the rail car and the LED
should go out.

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NOTE: It is BEST to set the timeout adjustment to zero so
that the LED will go out immediately after you move the
rail car. This makes confirming the correct operations
much easier.
If you are using the PRECISION DETECTOR™ with our MTT
Signal Controller or MTT Relays you will most likely want to
leave the setting to 5 seconds and let the Signal Controller
manage the signal light timing. If you are using our Sound
Module, then use the PRECISION DETECTOR™ timing to adjust
when to stop a sound after the train has passed. An example
would be a crossing bell sound. With our Fiber Lighting
Controller and a gate crossing use the PRECISION DETECTOR™
to set the timeout so the lights and sound stop at the same
time.
The PRECISION DETECTOR™ provides a DIGITAL signal output
(LOW) which is the kind used by many model railroad electronic
controls that you would normally hook up such as sound
modules, Light Controllers (like our Fiber and LED Controllers)
and Block Signal Controllers. This detector can be configured
to switch a relay that has a digital input option, but it cannot
power or switch the relay itself.