gca173-en
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| + | ====== GCA173 Hall-sensor annex reed-switch annex infrared converter. ====== | ||
| + | [[english|{{ | ||
| + | [[english|Content]] -> [[hardware-en|Hardware]] -> [[hardware-en# | ||
| + | * [[mgv-overview-en|The GCA modules]] | ||
| + | |||
| + | \\ | ||
| + | |||
| + | ^^^^By Peter Giling ^^^^ | ||
| + | |||
| + | | **This Unit is NOT 3V3 compatible, because Hall-sensors need minimal 5V.** | | ||
| + | |||
| + | |||
| + | \\ | ||
| + | ===== Introduction ===== | ||
| + | Quite a few systems are available now to detect the Loc, passing a certain area.\\ | ||
| + | Most of them require extra construction inside a loc.\\ | ||
| + | Sometimes, it is already available in the decoder, like Lissy or Railcom.\\ | ||
| + | But to receive these messages, it requires quite some expensive hardware.\\ | ||
| + | One other system , Maerklin' | ||
| + | any information about the exact position.\\ | ||
| + | The wheel-counter **[[mgv141-en|GCA141]]** together with Rocrail, is a system that will tell you at least \\ | ||
| + | that a train has entered completely into the block.\\ | ||
| + | But then, placing the IR transmitter and receiver is a very precise job, maybe not easy to fix for everyone.\\ | ||
| + | All the other systems do not give you any info about if the complete train has entered the block, without losing \\ | ||
| + | some wagons or couches on the track.\\ | ||
| + | This of course unless you will build-in Lissy transmitter | ||
| + | equipped with some way of drawing current from the rails, where the current detection on the track will pass that information to the computer.\\ | ||
| + | Reed-switches were very popular long before the digital era was emerged.\\ | ||
| + | But due to the very limited possibilities of magnets, and the fact that faster running trains sometimes ' | ||
| + | reed-switch made the use of it less popular.\\ | ||
| + | Even now, while we have many other ways of sensing the train on the track, a reed-switch might be sensible to use.\\ | ||
| + | But we have a better, and much smaller option now : Hall-sensors.\\ | ||
| + | These sensors, like the **[[http:// | ||
| + | are very small items, even usable for N-track, because this sensor only measures 4,2 x 3,3 x 1,5 mm.\\ | ||
| + | It even can be inserted inside the gravel, making it totally invisible.\\ | ||
| + | The other advantage we have now, is the availability of very strong and yet very small Neodynium magnets.\\ | ||
| + | |||
| + | | {{: | ||
| + | | An example of a very small 1x4x5 mm magnet under this Fleischmann N-track 781283 Loc | A small N-Track kipper with a (not glued !) 5mm cube magnet. | ||
| + | | {{: | ||
| + | | A small example of all different kinds of magnets available | ||
| + | \\ | ||
| + | |||
| + | This sensor is 3-wire connected and could be connected directly to a CAN-GC2. or GCA50.\\ | ||
| + | But why should we need this extra GCA173 ??\\ | ||
| + | First of all the connection itself, This pc-board makes that much easier.\\ | ||
| + | Than the pull-up ohm either GCA50 , CAN-GC2 or GCA-PI02 is 10K ohm, which should be much lower to have a solid distortion resistance.\\ | ||
| + | Also a capacitor of minimum 47 nF is needed, conform the data-sheet.\\ | ||
| + | CAN-GC2 needs pulses from feed-back with a minimum lengt of 25 mSec. For GCA50 even the minimum is 80 mSec.\\ | ||
| + | The GCA-PI02 needs minimum of 10 mSec.\\ | ||
| + | That makes them practically not suitable for this hall-sensor, | ||
| + | To explain that let us make some approximate calculations. **:** \\ | ||
| + | If we have a distance of 5mm between magnet and hall-sensor, | ||
| + | A HO train, running in scale 120 km/h runs in reality 380 mm per second.\\ | ||
| + | If the sensor only ' | ||
| + | A pulse like that is bound to fail, because the pulse will be only 1/4 of what we need.\\ | ||
| + | The CAN-GC2 and GCA-PI02 are better (=shorter) but still way too critical.\\ | ||
| + | GCA173 is here to take care for that\\ | ||
| + | It has connectors for 8 sensors, either hall-sensor or reed-switch.\\ | ||
| + | A small and cheap microprocessor on GCA173 checks continuously all 8 inputs, and will react when one or more inputs are going low, to forward this signal to either GCA50 or CAN-GC2.\\ | ||
| + | Even if the input is no more than 2 millisecs, the output will remain high for 150 milliseconds, | ||
| + | The hall-sensor itself is much faster than that (approx 1 uSec), so the chance that a train will be ' | ||
| + | One other extra advantage of using the GCA173 as a buffer, is that we will have enough connections for all eights sensors.\\ | ||
| + | In case of direct connection between CAN-GC2(GCA50) and 8 hall-sensors, | ||
| + | |||
| + | \\ | ||
| + | |||
| + | ===== Features ===== | ||
| + | * Easy connection of up to eight individual sensors and or reed switches.\\ | ||
| + | * Each input will be passed through with a minimum pulse length of 100 mSec.\\ | ||
| + | * Low impedance input takes care for high distorsion immunity.\\ | ||
| + | * Even for reed-switches , the low input current is exactly right, to keep the reed-switch in good shape.\\ | ||
| + | * 1 cable connection to GCA50 / CAN-GC2 / GCA_PI02 / WIO-xx / G-ASH02, which also feeds this board with 5 Volt.\\ | ||
| + | * Very low power consumption when all inputs are inactive.\\ | ||
| + | * Led signal on each individual input to simplify testing.\\ | ||
| + | |||
| + | ===== Counting Rolling stock ===== | ||
| + | The big advantage of this system is the fact that you will be able to detect if the train has entered completely into the block.\\ | ||
| + | As you are used from Rocrail, this fabulous program also does have a standard setting for this sensor, called 'Wheel counter' | ||
| + | Except here we are not counting wheels but Magnets. But the result will be the same.\\ | ||
| + | At least two magnets should be mounted under the train, the last one under the last wagon.\\ | ||
| + | When these magnets have announced themselves on entering the target block, the conclusion is safe to assume that \\ | ||
| + | nothing is left behind in a tunnel or shadow station, so the computer will proceed with clearing the used route and use it again.\\ | ||
| + | The sensor itself will be programmed as **[[: | ||
| + | Rocrail will automatically use this counter after the first initiation, and take over this info,\\ | ||
| + | If you like, more than one extra magnet is an option, even different trains with different number of magnets is an option.\\ | ||
| + | With that installed you could even distinguish which train did come in, but that is an option, not yet available in Rocrail. (Is not planned.)\\ | ||
| + | Commuting trains should be equipped with at least two magnets, so sensors will work in both directions, | ||
| + | and make the train stop at the first detected magnet.\\ | ||
| + | \\ | ||
| + | |||
| + | ===== One neww interesting option with GCA173 ===== | ||
| + | |||
| + | With the introduction of | ||
| + | \\ | ||
| + | |||
| + | ===== Handling in Rocrail ===== | ||
| + | Rocrail compares the counted wagons from the **From** with the **To** block: | ||
| + | * No comparison is done when one or both blocks are reporting zero. | ||
| + | * Normal (done by the " | ||
| + | * In case the **To** block reports less then the **From** block the loco is cancelled from auto mode and the **From** block is closed. | ||
| + | * After the lost material is connected to the train again, the **From** block can be set to action, and the train can be re-activated to auto mode. | ||
| + | |||
| + | |||
| + | |||
| + | |||
| + | ===== Boards available ===== | ||
| + | |||
| + | A nice double sided board, with through hole metallisation and silkscreen print is available now.\\ | ||
| + | {{: | ||
| + | |||
| + | ===== Magnets ===== | ||
| + | |||
| + | A large variety of magnets is available from www.phgiling.net: | ||
| + | |||
| + | ^ Type ^ Size ^ | ||
| + | | 1 | Cylinder 4mm ∅ length 12,5 mm | | ||
| + | | 2 | Cylinder 4mm ∅ length 10 mm | | ||
| + | | 3 | Cylinder 3mm ∅ length 8 mm | | ||
| + | | 4 | Cylinder 3mm ∅ length 6 mm | | ||
| + | | 5 | Disc 5mm ∅ high 3 mm | | ||
| + | | 6 | Cube 5mm | | ||
| + | | 7 | Plate 5 x 4 x 1.5 mm | | ||
| + | | 8 | Plate 5 x 4 x 1 mm | | ||
| + | | 9 | Plate 5 x 2,5 x 1,5 mm | | ||
| + | | 10 | Plate 5 x 1,5 x 1 mm | | ||
| + | | 11 | Plate 10 x 4 x 1 mm | | ||
| + | \\ | ||
| + | Magnets are only sold in sets of 8 pcs per size.\\ | ||
| + | |||
| + | ===== Correct position of magnets ===== | ||
| + | Magnets have two poles, of which only one will activate the sensor.\\ | ||
| + | Before putting magnets on your rolling stock, please check the correct position.\\ | ||
| + | This can be done by checking with a sensor itself.\\ | ||
| + | Sensors should be with marked (rounded) side facing towards the magnets.\\ | ||
| + | |||
| + | ===== Safety precautions ===== | ||
| + | |||
| + | |||
| + | //**These very strong NeoDynium magnets are no toys !!!!!**//\\ | ||
| + | In principle they are safe by itself, but please be careful with these magnets , do not allow children play with it.\\ | ||
| + | There are quite a few safety remarks, downloadable here : {{http:// | ||
| + | |||
| + | |||
| + | |||
| + | ===== Connection Hall sensor ===== | ||
| + | |||
| + | The connection wires between Hallsensor and GCA173 can be up to 6' or 2 meter.\\ | ||
| + | Please be careful not to feed those wires parallel with rails and rail wires.\\ | ||
| + | A bit of twisting these wires will inprove protection to any distorsion.\\ | ||
| + | If that is inevitable, keep a distance of 4'' | ||
| + | Straight angle crossing is no problem.\\ | ||
| + | Below you can download a drawing of hallsensor connection.\\ | ||
| + | |||
| + | {{: | ||
| + | |||
| + | The #1 leg of the tle4905 connects with #1 connector to the gca173, the " | ||
| + | |||
| + | ===== Connection to reed-switch ===== | ||
| + | Allthough GCA173 can work fine with reed-switch as well, the option for wheel counter is NOT applicable.\\ | ||
| + | This due to the fact the the number of pulses, generated on the passing of a magnet is never the same, and unpredictable.\\ | ||
| + | {{: | ||
| + | |||
| + | ===== Cable to GCA50 / CAN-GC2 / CAN-GC4 ===== | ||
| + | |||
| + | refer to: | ||
| + | [[PSK-Interface connections-en|**Connection interfaces**]]\\ | ||
| + | |||
| + | ===== Connection table of J1 ===== | ||
| + | ^ J1 pin# ^ Function | ||
| + | | 1 | +5V | Supply GCA173 | ||
| + | | 2 | 0V/ | ||
| + | | 3 | Hall1 | output sensor 1 | | ||
| + | | 4 | Hall2 | output sensor 2 | | ||
| + | | 5 | Hall3 | output sensor 3 | | ||
| + | | 6 | Hall4 | output sensor 4 | | ||
| + | | 7 | Hall5 | output sensor 5 | | ||
| + | | 8 | Hall6 | output sensor 6 | | ||
| + | | 9 | Hall7 | output sensor 7 | | ||
| + | | 10 | Hall8 | output sensor 8 | | ||
| + | |||
| + | ===== Hardware ===== | ||
| + | |{{: | ||
| + | |{{: | ||
| + | |{{: | ||
| + | |{{: | ||
| + | ^N.B. Self made pc-boards are not supported! ^ | ||
| + | \\ | ||
| + | \\ | ||
| + | ^ Housing is only for DIY 3D printing. | ||
| + | | {{ : | ||
| + | \\ | ||
| + | ===== Firmware ===== | ||
| + | {{: | ||
| + | This latest 1_4 version is published, because it has a more accurate timing before resetting the output.\\ | ||
| + | Timing is close to 80 mSec.\\ | ||
| + | {{: | ||
| + | Version 1_5 has a better startup sequence. It will initial send all actual sensor positions\\ | ||
| + | |||
| + | ===== Pictures from satisfied customers ===== | ||
| + | | {{: | ||
| + | | 3 wires connected to sensor \\ middle wire isolated | ||