Adding light to Doorway Sensor

Discussion in 'Electronics & Electrics' started by glenpinn, Mar 15, 2020.

  1. glenpinn

    glenpinn Member

    Joined:
    Dec 11, 2006
    Messages:
    5,882
    Location:
    Hobart
    Hi everyone, just curious if there might be a way to add a small LED light of some kind to the following mains powered Doorway Beam Sensor, either by replacing the alarm speaker with a light, or adding a light to the alarm speaker itself.

    https://www.jaycar.com.au/commercia...-L-GOwmBbr7acbXGz887jQ3GeHqIfA6xoCctoQAvD_BwE

    Any possibility, or is there such a Beam Sensor available that actually includes a light of some kind.

    Cheers
     
  2. Technics

    Technics Member

    Joined:
    Apr 29, 2002
    Messages:
    2,006
    Location:
    Brisbane, AU
    Well the manual says it had an NPN output (which implies an open collector wiring) and the extension speaker you can get shown it uses a 3.5mm stereo plug (and doesn't require external power). It's likely that the three pins are supply, ground and alarm (pulled to ground when active). This would be easy to verify with a meter. It would be trivial to use this to light an LED. With the anode connected to the supply via a current limiting resistor (suitable for the 12V supply) and the cathode connected to the alarm output. The issue would be that the output may only light the LED while the beam is blocked and this may not be ideal if someone quickly walks through the beam. In that case a retriggerable monostable timer circuit might be a good addition as it would keep the LED lit for a short period after breaking the beam. The speaker likely contains such a timer circuit to ensure the chime operates as expected and you may be able to access a suitable signal from it internally.
     
  3. OP
    OP
    glenpinn

    glenpinn Member

    Joined:
    Dec 11, 2006
    Messages:
    5,882
    Location:
    Hobart
    Thanks for that, seems like too much hassle, but i am wondering if the small Red LED light stays on until the beam is broken (by a car for example) then the light goes off, and stays off until the car is moved so the beam is re-activated and the light goes back on.

    If it did stay on, and goes off as the beam is broken, then i could mount the sensor body and the reflector on opposite walls in the garage, and at a height that allows me to see the small red light from inside the car, and stop the car as soon as the light goes off, or i hear the alarm go off.
    The thing i like about this kit is that it has a fairly long range of about 6m (my garage is 4.5m wide) and it is powered by plugging into the mains power, not operated by batteries.

    [​IMG]
     
    Last edited: Mar 16, 2020
  4. Technics

    Technics Member

    Joined:
    Apr 29, 2002
    Messages:
    2,006
    Location:
    Brisbane, AU
    That makes more sense. I didn't understand your use case was to detect a vehicle. For that, no timer circuit would be required. Yes I would expect the internal LED to stay illuminated while the beam is unbroken. I would also expect the output to remain low while the beam is broken. The wiring would be fairly trivial but you would need to use a multimeter to work out the wiring of the output jack.
     
  5. OP
    OP
    glenpinn

    glenpinn Member

    Joined:
    Dec 11, 2006
    Messages:
    5,882
    Location:
    Hobart
    Yes it is for detection of our new SUV as it enters our garage, but not as a security measure.

    We built a new Laundry along the front wall of our garage, the rear wall has a roller door, and with our new Forester parked inside the garage with the rear bumper 50mm from the roller door, we are left with only 700mm between the front of the bumper to the benchtop of the laundry and washing machine (the ASX we had was 1200mm) and we need access to the benchtop and washing machine while the vehicle is parked in there, so we decided to look for some kind of sensor device attached to a light or an alarm that we could set up so that we could stop the vehicle 700mm from that laundry and still be able to close the roller door.

    We initially thought of the following Striker system, however it was going to be a lot more difficult for me to set this type of kit up on the front wall (where the laundry is) than it would be to have a beam detector type system mounted on the 2 side walls of the garage.
    The biggest issue for me with this system would be the placement of the actual sensor, as well as the fact that this kit only operates on 4x AA batteries, and i have read reports that it can be a bit dodgy in the way it actually works, such as batteries not lasting very long, the preset distance selected is not always accurate (which i do need) as well as a few other issues which i won't go into here.

    https://www.roadrunneroffroad.com.au/00246-striker-ultrasonic-parking-sensor

    I did a google search on the Jaycar Commercial Doorway Sensor kit and it turns out to be a brand called Tech View, and i found one for sale at a cash converters store for $15, so i just bought it to see what it is like, beats paying $79.95 from Jaycar, so it should arrive tomorrow so i can test it out.
     
  6. Technics

    Technics Member

    Joined:
    Apr 29, 2002
    Messages:
    2,006
    Location:
    Brisbane, AU
    What about the old tennis ball and string system?
     
    Andy3008 likes this.
  7. OP
    OP
    glenpinn

    glenpinn Member

    Joined:
    Dec 11, 2006
    Messages:
    5,882
    Location:
    Hobart
    I know all about the tennis ball and string method (plus others) but it is not the method that i want to use, so i am going to try out the Tech View sensor kit and see how it goes, if that fails then i could look at other options such as the string and ball.
    I am a bit of a gadget person as well, so trying this sensor kit should be interesting as i have not done something like this before.

    I am keen to see if i can mount the sensor and reflector in a position on each side wall that will enable me to see the small red LED light go off when the car has hit the beam, and if that does work, then i can turn off the alarm so it doesn't go off whenever someone walks past the beam.

    The garage is also used as my carpentry workshop during the day, so the new car is put outside the roller door during the daytime if my wife is not using it for work.

    With the ball and string method it would get bumped quite a lot, so i would have to place it up on a hook while i am working in the garage, and drop it back down when i leave the garage.
     
    Last edited: Mar 16, 2020
  8. Technics

    Technics Member

    Joined:
    Apr 29, 2002
    Messages:
    2,006
    Location:
    Brisbane, AU
    That's fair enough. I'd be hooking up an external LED just so I didn't have to look sideways at the sensor while trying to look where I'm going.
     
  9. OP
    OP
    glenpinn

    glenpinn Member

    Joined:
    Dec 11, 2006
    Messages:
    5,882
    Location:
    Hobart
    Actually from what i can work out so far, i won't be looking sideways exactly, as in 90 degrees, i would be more looking at about 45 degrees to the right of me from front on, as the sensor will be placed on the drivers side and the reflector over on the passenger side wall, and both will be aligned to a height and position that will detect the outer most edge of the bonnet hitting the beam, and this would make the sensor body at about 1m to 1.1m from the floor, so it should be very easy to see that small light when glancing sideways, or at least hear the alarm if the light is too small to see properly.

    Also, given that the sensor will be placed 700mm in front of the laundry bench, i should not have to be looking towards the front once i have driven close enough to the sensor, i just glance sideways and stop the car as soon as the light goes off, of coarse keeping a bit of an eye open towards the front just in case it fails.

    Can't really see any issue with this working out the way i hope it will, but a separate LED light attached to the actual alarm box using a cable would make it a lot easier, which is why i posted this topic in the first place, to ask if a light could be attached fairly easily.
     
    Last edited: Mar 16, 2020
  10. Technics

    Technics Member

    Joined:
    Apr 29, 2002
    Messages:
    2,006
    Location:
    Brisbane, AU
    If you work it out without needing an external LED then great. If not we should be able to help you figure out how to wire it up once you get the unit and provided you have access to a basic multimeter. It looks like it uses a 3.5mm phono plug for the connection but it's best if you check once you have the unit.
     
  11. OP
    OP
    glenpinn

    glenpinn Member

    Joined:
    Dec 11, 2006
    Messages:
    5,882
    Location:
    Hobart
    No probs, it should be here tomorrow or Wed as i had it posted via express post, i will find the best location to attach it, and report back, with photos i need be.

    I also want to thank you for not going off tangent by trying to push me towards another "simple" option like the ball and string method, or just bolting a block of wood on the floor where the front tyre needs to stop to leave the required space, or just draw a vertical line on the wall where the mirror is and just line them up as i/we drive into the garage.

    Cheers

    BTW this is the inside of the garage in question.

    [​IMG]
     
    Last edited: Mar 16, 2020
  12. merlin13

    merlin13 Member

    Joined:
    Apr 12, 2003
    Messages:
    1,953
    Location:
    back in BrizVegas
    Pffft - a real Foz driver would park it in there sideways. That'd give you a metre more or so clearance to the bench, wouldn't it?... ;)

    Anyway, enough frivolity.

    Ultrasonic or laser proximity/distance sensor attached the bench, buzzer and/or indicator light set at suitable location. That why you also get a clearance indication if/when you ever reverse the Foz in.

    Else if you're a gadget man, a laser pointer attached to the ceiling, pointing straight down on to a suitable position on the bonnet or even the dashboard, triggered off a suitable motion sensor as well.

    And if If you really want to go all out, maybe look at grafting position sensors into the front (and rear) bumpers of the Foz?... That might also help with parking out in the real world perhaps.
     
  13. OP
    OP
    glenpinn

    glenpinn Member

    Joined:
    Dec 11, 2006
    Messages:
    5,882
    Location:
    Hobart
    Well we only had the FOZ for 2 weeks, still getting used to the size compared to the ASX we had before :D

    Any links to some possible solutions you have mentioned ?

    Got an email from the place where i bought the Tech View Doorway Sensor yesterday, should be in the post by end of business today, will set it up and report back.
     
  14. merlin13

    merlin13 Member

    Joined:
    Apr 12, 2003
    Messages:
    1,953
    Location:
    back in BrizVegas
    Well, I've used these types of critters to control 5 metre 12 volt LED strips in garages and small workshops/sheds.

    Powered it all off the small 12 volt 3 or 5 amp powerpacks normally used for feeding the LED strips. In a couple of instances I've actually set them up to run off car 'n SLA batteries for camping.

    With your need there you might need to fiddle with the sensor sensitivity, either finding one with suitable adjustment or even covering up the sensor such as the deaden the detection area.

    Honestly NFI on where to acquire low-voltage lasers, not had a need to play with them for a coupla decades.

    But if you want to use those then should be relatively easy to grab a small laser pointer or two and graft some sort of voltage step-down thing onto them to replace the batteries. Obviously fiddle with the On/Off button to suit as well.
     
  15. OP
    OP
    glenpinn

    glenpinn Member

    Joined:
    Dec 11, 2006
    Messages:
    5,882
    Location:
    Hobart
    Got the doorway gadget today, tested on the workbench, all seemed good, so i attached the sensor to the side of a 75x75 steel post which happens to be located right next to the drivers side mirror, which allowed me to set the sensor and reflector up on the opposite wall to detect the drivers side windscreen pillar as it hits the beam.

    I set it up so the car is 75mm inside the roller door, and i tested it dozens of times, and it seems to be very accurate, i got it within 10mm most of the time.

    The red light is small, you could not see it very well unless the sensor was close to the window of the car, so with my setup, i can see the red light go off very easily as the sensor is only about 1m from my face at almost right angles to the window.

    I couldn't film any video tonight but i will do tomorrow, but i did shoot some footage while testing it on the bench today (link below)

    The speaker has a Chime and an Alarm setting on the side, select the one you prefer, on the back is 2 screws to set the timer and the volume, but the Chime only works once for about 5 seconds, regardless of the timer setting, however the Alarm is much different, that thing is more like a police siren, and it is very loud when on full volume, and on the longest timer setting it goes off for about 20 seconds, certainly loud enough and long enough to scare robbers away if that is what you was setting these up for.

    Because this system has been set up in my garage to set the car distance to the laundry bench, i can only use the red light on the sensor to alert us when the car is in the right spot, so i just need to turn the speaker switch to the OFF position to stop the alarm/chime from making a noise, and we just glance at the sensor and wait for the red light to turn off.

    This is a short video of the sensor set up on my work bench, click the link and open the video to play.

    https://cp.sync.com/dl/f55bc8cd0/6vq78cuw-xqu2iszz-agxwtu7a-acg22b4u
     
    Last edited: Mar 18, 2020
  16. OP
    OP
    glenpinn

    glenpinn Member

    Joined:
    Dec 11, 2006
    Messages:
    5,882
    Location:
    Hobart
    Video of the Doorway Sensor in action, had it installed 2 days now and very happy with it, i currently have the single Chime on low volume for now, but because the sensor is located where it is, we are always walking past the beam and it gets annoying, so i will be turning it off tomorrow so we just need to look for the red light going off instead.

     
    Last edited: Mar 21, 2020
  17. merlin13

    merlin13 Member

    Joined:
    Apr 12, 2003
    Messages:
    1,953
    Location:
    back in BrizVegas
    So you now need another sensor to control that sensor when you're actually moving a car?... ;)
     
  18. mtma

    mtma Member

    Joined:
    Aug 12, 2009
    Messages:
    5,244
    We had a similar problem but we went with wheel chocks at the front and a guard beam at the back.

    Guard beam is linked to the door so that if the door isn't in the fully up position it will warn you if you reverse. Helps prevent those antenna snapping moments when the door's stopped part way.
     
  19. OP
    OP
    glenpinn

    glenpinn Member

    Joined:
    Dec 11, 2006
    Messages:
    5,882
    Location:
    Hobart
    Not sure what you mean ?

    I didn't want to use any other method except for the sensor type, if i used wheel chocks i would have to shift them all the time as i use the garage as my carpentry workshop every day and i would be tripping over them, then i would have to put them back in place when i leave the garage, too much hassle for me, easier to set the sensor up and just drive the car until the light goes off, or if i turn the alarm/chime on we just need to listen for that to sound to let us know the car is in the right place.

    The same thing applied to the string and tennis ball method, i would have to tie that up while using the garage each day, and drop it back down before the car is driven into the garage, and also when our roller door goes up we sometimes get wind blowing in, which would cause the ball to move around.
     
  20. merlin13

    merlin13 Member

    Joined:
    Apr 12, 2003
    Messages:
    1,953
    Location:
    back in BrizVegas
    Follow The Bouncing Ball - if your new parking sensor now triggers when you walk past it, you thence need another one that'll disable it until it actually detects a large metallic mass (ie a vehicle) coming into the garage. At which point the parking sensor is then enabled.

    Never heard of Rube Goldberg?...
     

Share This Page

Advertisement: