INSTRUCTIONS FOR THE SA-6
All the storage siding diagrams have been drawn for three sidings however any number of sidings can be operated.
Operation
The SA-6 operates as follows:
When a train is detected by the IRDOT-1 (I) at the approach to the storage sidings it will gradually reduce speed to an adjustable minimum speed. Detection by the IRDOT-P (at the end of the storage sidings) will switch the points to the next track and cause the SA6 to switch power off the track for an adjustable delay time. At the end of the delay time the next train will depart gradually accelerating up to the maximum speed.
INSTALLATION
First install the IRDOT-P's so that they are wired to the point motors, connected to a power supply and are operating the points in the correct sequence. i.e. on activating each IRDOT-P the points are switched for the next siding. See IRDOT-P instructions.
The IRDOT-1, SA6 control electronics, and IRDOT-P's must all use the same power supply. See below:
The diagram shows terminal "6" of the IRDOT-1, terminal "OV" of the IRDOT-P's and terminal "0" of the SA-6 connected to the negative or 0 Volts connection of the power supply. Terminal "1" of the IRDOT-1, terminal "+" of the IRDOT-P's and terminal "+" of the SA-6 all connect to the positive (or 12 volts) connection of the power supply. Alternatively all the units can be powered from a 16 volts AC supply.
Install the IRDOT-1 train detector at the approach to the storage sidings at the position where it is required for the trains to start braking. Terminal "2" of the IRDOT-1 is connected to terminal "D1" of the SA6.
Also connections are needed from each of the "P" terminals of the IRDOT-P's these can be made to either terminal "D2" or "D3"of the SA6. These connections are to tell the SA6 when a train has reached the IRDOT-P position. Operating "D2" or "D3" causes the power to be switched off the track for the time interval set by the timing "pot". At the end of this time the minimum speed power will be connected to the track and it will increase to the maximum setting according to the rate of acceleration set.
Terminal "D2" and "D3" both give identical operation. The reason for having two terminals is to simplify wiring when the SA8-S or SA5-S are used with the SA6. Both the SA8-S and SA5-S have a "next train is non stop" terminal". This is to allow goods trains or express trains to travel through a station without stopping. If each siding (at which a train arrives) before the non stop train has terminal P of its IRDOT-P's wired to terminalD2. Each siding before a stopping train has its terminal P wired to terminal D3. A single wire is run from terminal D2 to the non stop terminal of the SA8 or SA5. The operation now is that a train arrives at the IRDOT-P connected to terminal D2 and the non stop terminal receives a pulse so that the next train to leave will be non stop. However if a train arrives at an IRDOT-P with its P terminal connected to D3 the non stop terminal will not receive apulse so the next train to leave will be a non stop train.
Finally the inhibit "I" terminals of all the IRDOT-P's need to be connected together and connected to the terminal of the SA6 shown in the diagram. These connections allow the SA6 to prevent operation of the IRDOT-P point switching for departing trains. This is necessary to prevent the departing train operating the IRDOT-P it is passing over. This would change the points and so derail the train. The SA6 ensures that the IRDOT-P's cannot switch the points until a train is detected at the train detector at the entrance to the sidings.
Track Power Connections
Separate connections are provided to power the control electronics and the track.
This allows the choice of either powering everything from a 12 volt DC or 16 volt AC supply or powering the track separately through a conventional controller. Using a controller in this way gives normal control outside the storage sidings with no sudden speed changes on crossing to the storage sidings. The controller setting governs the maximum speed the SA6 can accelerate trains to.
Powering everything from a single AC or DC supply is more applicable to a completely automated system. The maximum speed is set by the "max speed" pot of the SA6.
Train controller
The wire link is removed. Either a 12 volt DC supply or a 16 volt AC supply is connected as described previously to power the control electronics, the IRDOT-1 and the IRDOT-P's. Insulation gaps are put into the rails either side of the storage sidings leaving a length of track long enough for the acceleration and braking within the isolated area. The controller is connected to the track in the normal way outside these sections. The controller is also connected to the SA6 unit. The track inside the isolation sections is powered from the SA6 track output. If electrofrog type points are used rail breaks will be necessary in the centre of each loop line (see wiring instructions with points).
12 volt DC supply only
Leave the wire link in place and connect the 12 volts D.C. supply as described previously.
TESTING AND SET UP ADJUSTMENTS
This is best carried out in the following order.
Turn the variable resistors with a fine screwdriver to give delay time=short, min speed=slow, max speed=fast, CC/BR (rate of braking/acceleration)=abrupt.
It is necessary to have one train for each storage siding. Start with either all the trains in the storage sidings or with one train outside. After the variable delay (green and red flashing) one train will quickly accelerate to maximum speed. When the train is detected by the IRDOT-1 at the approach to the sidings it will rapidly reduce speed and halt. Adjust the min speed setting until the train just moves. It will then travel to the IRDOT-P at the end of the line and the points change. The red and green LED's should now flash alternatively for the delay time. At the end of which the green LED will light continuously and the next train in the sequence accelerate away. Adjust the maximum speed setting to the required speed (unless using the controller to determine the max speed in which case the maximum speed should be left at max). As successive trains brake on approach to the sidings adjust the acc/br setting so that the train slows to the minimum speed just before reaching the IRDOT-P. Some further adjustment of the minimum speed setting may be required to suit the worst performing locomotive.
Note: min and max speed adjustments are confusing to set unless acc/brake is set to abrupt because of the effect of electronic inertia.
Finally adjust the delay time setting to the desired time. Note that the length of the flashes is proportional to the delay time.
Overload protection
Overload protection is built into the SA6. If an excessive current is drawn from the unit then the overload circuit will prevent the unit from being damaged by switching off power to the track. This fault condition is indicated by the red and green LED's both lighting. As soon as the fault is rectified the unit will resume normal working.
POWERING FROM 16 VOLTS AC:
The SA6 and IRDOTs can be powered from 16 volts AC. This requires the link wire to be replaced by a diode. The band on the diode must be in the direction shown.. If AC is used the output at the track will be half wave rectified DC. If a 12-volt DC supply is used the output at the track will be pure DC. The capacitor can be used. This will smooth the DC. The side of the capacitor with the minus signs and arrows must connect to the terminal shown.
Heathcote Electronics, 1 Haydock Close, Cheadle, Staffs, ST10 1VE, Tel/Fax 01538 756800
Email web site www.heathcote-electronics.co.uk
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