X 10 PIR Notes

Tinhorn

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Eagle Eye was kind enough to send me an X10 PIR to poke around on and see how it ticks.  There is an indoor and outdoor version, he sent the Indoor version.  This is a dandy little PIR that had a pretty good range that about matches the Owl PF's flash range and is very energy efficient.

I agree with Hamiltoe that there is only one place to tap into on the PIR for a Timer Trigger.  It requres an interface of some sort between it and the timer since it's signal is so weak.  Hamiltoe has been using a Comparator IC which is available from RS (special order) which works fine but I decided to build a one transistor circuit that will trigger the timer without the Comparator.  The PIR and interface circuit succesfully triggered a 2 stage timer made from TLC-555's and one of Brian's Timers IC's.  I didn't have one of JoeD's timers available (they were busy in some camera's) but since they are the same ICs as Brians, I'm sure it'll work with no problems (but don't forget they use different trigger pins)

With Brian's help, I found the specs for the 2 - ICs in the PIR on the Internet which said one of the IC's would operate up to 5.5 volts & the other up to 18v's.  I was hoping the PIR would run on 4.5 volts so both the PIR and timer could use 3 - AA's or 3 - "C" cells but apparently it's not the case.  After running about 4 hrs on 4.5 volts, the PIR's walk test LED began to glow continuously and it wouldn't detect motion.    Now that the testing is done, I will try it again just to be sure it was not a fluke.  I didn't want to toast it before completing all the testing!  If the PIR would happen to work on 4.5 volts, no changes would be required to the interface circuit.

Both JoeD's and Brian's timers will run on 3volts ( 2 cells) but the question is - how long before weak batteries falls enough below 3volts to cause a problem.  The PIR is very energy efficient and it and the timers together drew so little my digital meter was barely able to measure the current. Maybe Hamitoe or other X10 users will post their experiences on how long a pair of batteries has lasted but I bet it's months.  Eagle Eye told me he messed around with the PIR he sent me on the same AAA's for 8 or 9 months and the batteries were still good.  3 volts may not be a problem!  Mouser sells a 3 terminal, 3v energy efficient regulator which would allow using a 6 or 9v battery if desired tho.

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Here is a Quote from one of Eagle Eyes Emails:
    I use one of the Black and Decker Versa-Pak batteries to power the X10
    and timer. They claim to be 3.6v, but Ive had some charge up at 4.5v and
    haven't fried a sensor yet, dont know how much they will stand. I have got 3
    months of continous use before I switched batteries , when I got home and
    checked it, it was showing 3.7v, so it might have gone longer
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Here are some notes and a pix of the unit, along with the interface schematic.

Tinhorn

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http://www.nightowl.net/~tinhorn/PIR-Interface.jpg

Dimensions:
     overall case size = 2-1/2" X 2-1/2" X 1" square
     board size:         2-3/8" X 1-1/2"
     Distance from Sensor to Fresnel Lens ~ 1/2"  (not measured)

Batteries:
     According to Battery Life Calculations, 2 "C" cells would last
           in excess of 12 months (includes timer)

PIR Range:
     at 75 degrees in the shade of the house, the PIR reliably
     detected motion at 30'
PIR Walk Test:
     PIR has an existing red LED

PIR Modifications:
     1.  Remove Light Sensor
     2.  Add 3 wires as shown on Pix above
           the red wire is soldered onto the (+)battery connection
           the Black wire is soldered onto the (-) battery connection
           the green trigger wire is soldered on to PIN 5 of IC IS27L2cn
                the easiest place is on that resistor that is on an
                angle by the IC

Interface Circuit Notes:
    1.  Transistor is NPN, used RS's bulk pack of 15 transistors for ~$2 or $3
              (similiar to 2N3904)
    2.  R3 special note:
              if the idle voltage on the timer trigger pin is at or near the
              battery voltage then R3 is not needed
    3.  PIR Trigger Signal goes from battery (+) to LOW (near ground)
    4.  NOTE:  This PIR/Interface circuit REQUIREs a timer be used,
                 it won't trigger a camera directly
 

hamiltoe

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Tinhorn,
I have one of the X10's in my garage that turns on the lights for me.  The batteries lasted well over a year before I had to change them.  That's just a plain X10 PIR without any other circuitry attached to it.

I also noticed that the PIR has a very LARGE field of view.  I ended up masking the lens with a strip of electrical tape on each side to decrease the field of view.  The PIR also detects movement too far below the sensor, so I found it best to also mask of the part of the lens that senses downward.  I had a lot of blank pictures with another picture 30 seconds later with a rabbit or possum moving directly away from the camera which led me to believe that the PIR was sensing things below the camera but out of the camera's field of view.
 

Archilochus

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Great info Tinhorn!  You must have spent quite some time on that PIR.
>>>>

Here's a tip for anyone interested in using this sensor -  http://www.x-10.com is always having sales & specials.  Lots of "2 fer ones" and such.  Try signing up to their mailing list to keep on top of the latest.
Maybe ****** could buy up a bunch on sale and re-distribute them :)

Archilochus
 

Eagle Eye

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Thanks Tinhorn, very useful infomation. I owe you one.

Hamiltoe, thanks for the tip on masking off some of the bottom, that may be why I will sometimes get a few pics with nothing in them. I will give it a try.

Arch is right about sale, if you spend over $50 shipping is free.
 

Tinhorn

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Tinhorn

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There is a problem that might occur with the X10 that might happen in both Hamitoe's and my interface version if the external timer is set below 1 minute. A 2nd pulse 60 or 70 seconds later may retrigger the timer causing a 2nd pix to be taken! Not sure this occurs in Hamitoes design but I assume it would!

The Cure:

Lift the leg (or just cut out) the resistor just above the transistor located at the upper right corner of the pix I posted. (It's 100K, brown,black, yellow)

There are 2 resistors side by side, you want to lift the leg of the resistor closest to the transistor, it has R15 under it but you won't see this till you remove the resistor. Right next to this resistor, at least on my unit, is a missing resistor labeled RX.

This resistor passes the "2nd trigger pulse" from PIC IC U1 pin 3, down to IC U2, pin 6 and this pulse is the culprit, I think it's bleeding over to the trigger going to the NPN transistor off pin 5....

It don't matter which leg is lifted, the resistor just needs to be out of the circuit.

The Pix in the original post will be modified and will point to this resistor to remove.....

Sorry!

Tinhorn
 
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