Azatrax SHS Installation Manual

Installation Guide
What it is:
The SHS operates distant, home and starter signals on a single track at a station, generally following practice
derived from British railways.
Trains are detected by infrared sensors, independent of the room lighting. The rail does not need to be cut into isolated
blocks and resistor wheel sets on the train cars are not required.
LED signals must be used.
Signals with incandescent bulbs
need solid state relays such as
Azatrax model SSR6 between the
SHS and the signal.
The polarity of the
signals (common
distant signal, up
anode vs. common
cathode) is
automatically
Down
detected by the
SHS.
Train direction:
For single direction rail traffic, place the "down" (approach) sensor on the approach side of the station just past the home
signal. Place the "up" (departure) sensor some distance beyond the departure end of the station. The starter signal will
change from green to red when the head of the train trips the up sensor. The home signal will change from red to green a
few seconds after the rear of the train clears the up sensor.
For bi-directional rail traffic, place the sensors about midway between a
home signal and the opposing starter signal.
Kit contents:
Circuit board
♦
Infrared light-emitting diodes (IR LEDs) with orange & white wire leads
♦
Infrared photo receivers with green & yellow wire leads
♦
Plastic mounting tubes. The tubes are for protection of the sensor leads and to provide mounting support. They are not
♦
essential for detector operation and may be shortened or removed entirely to best fit your situation. Just use caution to
avoid damaging the leads.
This guide assumes an up/down direction of the track. If your track directions are east/west or north/south, make
appropriate substitutions -- and be consistent!
If using signals only for one-way traffic, install only signals for the "up" direction.
Install the sensors: Each sensor pair may be installed in one of two different ways - 'Across the Track' or 'Reflective.'
Across the Track sensing: The IR LED is positioned horizontally on one
side of the track, and the IR photo receiver is placed on the opposite side.
A train is detected when it blocks the light path between the LED and
photo receiver. The distance between the LED and photo receiver can be
up to 18 in. (46 cm), or more with careful alignment.
Tip #1 - If mounting the sensors vertically as shown here, slide the plastic tubes 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 photo receiver so it faces away from bright lights or sunny windows. Use scenery or structures to
conceal the sensors and shade them from room lighting.
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Azatrax Model Railroad Starter & Home Station Signal Control
optional
distant signal
Down
optional
home signal, up
down
sensor
SHS starter - home signal installation guide
"up" direction
home signal
down sensor
starter signal, up
station
starter
signal,
down
To allow the starter signal to automatically
Installation
starter signal
station
up sensor
up
sensor
home
signal, distant signal,
down
turn green, the end of the train must be
clear of the approach sensor when
stopped at the station. If not, manual
switch T1 or T2 will change the starter
signal to green (see pg 4).
SHS
Up
Up
optional
down
pg. 1 of 4