Twins_sasa Posted December 21, 2005 Report Share Posted December 21, 2005 i had bought a motion detector(Paradox DG55). It has 6 pins: N.C, COM, +i/p. -i/p, 2 pins for anti-tamper switch.Some info from the data sheet:Alarm output: Form A relay 100mA/28Vdc, N.C (optional form C relay 500mA/30Vdc, N.C/N.O)Anti-tamper switch: 150mA/28Vdc, N.CVoltage input:: +12VdcNormally motion detector is connected to alarm. But in my project, my idea is to connect the output of this motion detector to a ToothPIC microcontroller.So when motion is detected, the motion detector will send an output voltage which is connected to input pin of ToothPIC. So the ToothPIC microncontroller is activated everytime when there is an motion detected by the sensor.I'm not sure whether this idea is correct or not.And i want to measure the output voltage of the motion detector(because the input voltage of ToothPIC is only 5-10Vdc).My prob is i don't know how to connect those equipments together.Can anyone teach me how to connect the motion detector with power supply and which pins to be tested with multimeter in order to get the sensor output voltage???High appreciation to all of u guys reply and help.Thanks very much.i guess it don't have N.O because in the data sheet is stated "N.O optional": Form A relay 100mA/28Vdc, N.C (optional form C relay 500mA/30Vdc, N.C/N.O) , am i right??? Quote Link to comment Share on other sites More sharing options...
Twins_sasa Posted December 22, 2005 Author Report Share Posted December 22, 2005 from the power supply, i connect the +12Vdc to +i/p, then ground should go to -i/p or COM?since the sensor only have N.C and COM, i/m wondering does it mean when motion is detected, the N.C relay switch will open and no output voltage will trigger the PIC. Is my concept correct?pls advise. thanks very much. Quote Link to comment Share on other sites More sharing options...
audioguru Posted December 22, 2005 Report Share Posted December 22, 2005 Won't 12V applied to the input of a ToothPIC blow it up?Connect the detector's COM to the ToothPIC's ground.Connect the relay's contact and a 10k pullup resistor (from the ToothPIC's supply) to the input of the ToothPIC.The normally-closed relay contact will apply a logic low to the ToothPIC when there is no motion. When motion is detected then the relay contact opens and the pullup resistor applies a logic high to the ToothPIC.The normally-closed contact detects tampering. When the wires are cut then you get an alarm. A smart thief would just short the relay contacts then you need another method to detect him. Quote Link to comment Share on other sites More sharing options...
Twins_sasa Posted December 22, 2005 Author Report Share Posted December 22, 2005 thx very much for audioguru reply.But the N.C and pullup resistor connected to ToothPIC input are as series or parallel? Quote Link to comment Share on other sites More sharing options...
Twins_sasa Posted December 22, 2005 Author Report Share Posted December 22, 2005 thx very much for audioguru reply.But the N.C and pullup resistor connected to ToothPIC input are as series or parallel?i mean is it place the pullup resistor between the ToothPIC input and the N.C contact?orplace the pullup resistor between the ToothPIC input and a +Vcc?? if so, the +Vcc should be +12Vdc (same source wit detector +12V i/p) or another pwr source +5Vdc (ToothPIC i/p requirement)?? Quote Link to comment Share on other sites More sharing options...
audioguru Posted December 22, 2005 Report Share Posted December 22, 2005 The Vdd of a ToothPIC is +5V. Input voltages must not exceed +5.5V. You can power its built-in 5V voltage regulator with +12V if you want.1) Connect the COM of the detector to the ToothPic's Vss (ground).2) On the ToothPIC, connect a 10k pull-up resistor from Vdd (5V) to the input to provide a +5V logic high.3) Connect the NC relay contact also to the the input of the ToothPIC to provide a logic low.When there is no motion the input is low. When motion is detected the input is high.12V operates the detector and no voltage is on its relay contact until you connect it to the ToothPIC's input with the pull-up resistor. Quote Link to comment Share on other sites More sharing options...
Twins_sasa Posted December 27, 2005 Author Report Share Posted December 27, 2005 ya, i followed your way and the sensor can work already.But when motion is detected, the output of the sensor is very small(<1V), unstable, discontinous and only trigger for around 3 seconds. It's not as the expected +5V. After 3 seconds, it wil back to ready state(0V) again.This is not enough to trigger the ToothPIC to work properly.I plan to have a OP-AMP to boost the voltage. But how about the problem of discontinous output? Any idea or better solution for that? thank q very much for your advise. Quote Link to comment Share on other sites More sharing options...
audioguru Posted December 27, 2005 Report Share Posted December 27, 2005 But when motion is detected, the output of the sensor is very small(<1V)You said that the output of the detector is a normally-closed relay contact. The relay will open its contact when it detects motion. The 10k pull-up resistor to +5V allows the input to the ToothPIC to go to +5V, not less than 1V.unstable, discontinous and only trigger for around 3 seconds.After 3 seconds, it wil back to ready state(0V) again.Maybe that is the normal operation of the motion detector. Quote Link to comment Share on other sites More sharing options...
Twins_sasa Posted December 28, 2005 Author Report Share Posted December 28, 2005 yaya..sorry..you are right, i made a mistake.i got the "unexpected output" is because i connect wrongly some wiring.ya, the output is +5V when moton is detected. But it only last for 3 seconds, then the sensor will go back to ready state (0V). How to make the output voltage last longer so that the ToothPIC can have enough time to perform its task? (last 10seconds will be good enough).Appreciation and Thanks for helping. Quote Link to comment Share on other sites More sharing options...
audioguru Posted December 28, 2005 Report Share Posted December 28, 2005 You can make a 10 seconds timer from a 555 IC. Its details are in our Articles section and in its datasheet:http://www.datasheetarchive.com/semiconductors/pdfdatasheet.php?Datasheet=1136921 Quote Link to comment Share on other sites More sharing options...
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