How To Test A Wired Motion Sensor Without Alarm Panel

ccmichaelson

Active Member
I'm starting to pre-wire my house and I have multiple locations I'd like to test whether a motin sensor would trip if a person walked by before I run my wires to that location. Is there a way to attach a motion detector to a battery (or something) so I could temporarily walk around the house and test it in multiple locations.
 
Battery and DMM with continuity function or a cheap 12VDC buzzer
 
Of course, that discounts the effect of the walls being closed, furniture, even wall treatments so you need to take what you determine as a rough coverage pattern with a slight grain of salt.
 
It's better to properly locate them and install more than put in only a couple and rely on higher sensitivity and miracle "trick shot" coverage. If you're doubting the person is going to be able to cross the detector's coverage pattern to begin with, it's location or distance is already in question.
 
Personally the older analog type DMM's have louder beeps than the newer digital ones (well from my experience). 
 
A 12VDC buzzer would be loudest.
 
You can also watch the LED on the device if you have it enabled to go on with motion - difficult to see the further you are from the device though unless the room is dark?
 
You can use that blue painters tape if you want for temp stuff or even little pins with big heads to temporarily hang a PIR.  Or just utilize the drawing of the PIR footprint that accompanies the instructions for the PIR you are utilizing and best guess your test position placement.
 
I'm okay with just seeing the led/light on the motion sensor.  What I don't understand is how to get power to it.  Can I just connect a 22 gauge burglar alarm wire to a 9 volt battery, AA battery, C batter, a car battery, or some other power source that is portable?  The motion sensor I am planning on testing is the Bosch Blue Line Gen 2 tri-tech.
 
Sure, just run a length of wire from the battery to the motion detector.  I'd use a 12V battery rather than a 9V, as 9V is at the lower end of the acceptable voltage range for the Bosch detectors.   To get 12V, you can use a single 12V battery, like a car battery or SLA battery, or put eight 1.5V batteries in series.  You could also use a 12VDC wall wart if you have one.  Just make sure it is really DC and not AC, and be sure to get the polarity right. 
 
You can make the PIR portable if just using the LED illuminator by using one of those tiny 12VDC lithium batteries DIYing the connection to the positive and negative power terminals inside of the PIR.
 
Use that stick'em clay putty like stuff to stick the PIR on the wall. Stuff works good and the PIR is light.
 
So I found an old wall wart from a radio scanner that states:  Output DC 12V 200mA
 
Could I cut the wires and connect the black/white wire to the + on the motion sensor and take the all black and connect it to the - then plug it into an electrical outlet?  I don't want to fry my new motion sensor.
 
Output DC 12V 200mA
 
will not fry new PIR.
 
The older wall warts were not regulated and you may see more than 12VDC coming from it.
 
The newer ones are regulated and typically you see 12VDC coming from it.
 
When you cut the wires on the old wall wart check the voltage and the polarity with a VMM and make sure as stated by RAL above you get the polarity right.  Don't guess.
 
Pete - you were right (no surprise).  I cut the wires and the voltage is reading about 15DVC volts (not 12) and amps were around 1.45.  Will this still work?  Otherwise I'll find another wall wart to test with.
 
Top end of the voltage for the detector.
 
Would work, but not the best. You could wire a large diode in series with the feed if you were concerned. I'd still recommend using a buzzer compared to relying on the LED. The Bosch units do have adjustments that would also need to be considered prior to accurately determining the coverage patterns, especially with no sheetrock masking out areas.
 
15VDC is the upper limit of what the Bosch PIR specs for an operating voltage.  I'm guessing you measured the voltage with nothing connected, in which case the voltage will drop a bit when you put an actual load on it.  
 
If you put a 2.2K resistor across the wall wart's output, and measure the voltage across the resistor, that will give you a better idea of what the voltage will be under load.
 
How did you measure the current when you got a reading of 1.45?  I hope you didn't just put the meter on the Amps scale and connect it to the wall wart's output.  That would put what amounts to a dead short across the output, which probably didn't hurt the wall wart, but could blow your meter.  I'll guess that the 200 mA that you said the wall wart is capable of didn't do any damage to the meter this time around.  So consider yourself lucky!
 
The right way to measure current is by putting the meter in series with an actual load.
 
I'm a software guy so this AC/DC crap is foreign to me.  I cut the wires to my old wall wart and then plugged it into my electrical outlet.  I grabbed my Walmart voltmeter and connected the black wire to COM and the red wire to the 10A input.  I then switched the voltmeter on to the 10A setting.  I placed red cable on voltmeter to the wall warts black&white wire and the black cable to the solid black wire and got the reading 1.45.
 
My 15 VDC reading was determined when I switched the voltmeter's setting to 20V.
 
My motion detectors will be here in a couple of days - just want to make sure I don't fry them using the wall wart.  
 
They should be just fine. After all they run on a battery that can range from 9 volts to 15 volts under normal service.
 
LarrylLix said:
They should be just fine.
That second conditional is key in that sentence.
 
A 12V loop is generally never going to be above 13.5 on 99% of the installs out there, even with fully charged batteries. If the OP feels OK gambling a $30 part, so be it, but caution should still be warranted if the voltage is already on the top threshold of the manufacturer's specs. I'd look for something closer to the 12-14 range or a battery personally before going right at the extreme end of the spectrum.
 
So I walked around the house looking for a better DC option and recalled that I have a battery connected to my existing home's alarm panel.  It is a UB1280 that says "12V 8Ah" on the side (except it doesn't say where it's AC or DC - I'm sure smart people would know...I am clueless).  Could I connect my 22 gauge alarm wire to this battery to power my motion sensor (just for testing)?
 
Here's the link on amazon:  http://www.amazon.com/Battery-UB1280-PS1272-Security-System/dp/B00BSELQXC
 
DELInstallations said:
That second conditional is key in that sentence.
 
A 12V loop is generally never going to be above 13.5 on 99% of the installs out there, even with fully charged batteries. If the OP feels OK gambling a $30 part, so be it, but caution should still be warranted if the voltage is already on the top threshold of the manufacturer's specs. I'd look for something closer to the 12-14 range or a battery personally before going right at the extreme end of the spectrum.
 
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