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Help with PIR Counter circuit

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211

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I'm working on a small home project. It's basically a PIR connected to a counter. I want to set this up in a location and count the times a human passes by.

I've picked up one of **broken link removed** which comes complete with it's own amplifier (hoping to cut out some of the prototyping involved). The output of this goes to the counter input of an Omron counter (totalizer) which I've cannibalized so I'm left with just the LCD display and circuit board (basically minus the battery). Both the PIR and counter now share the same 5V power source.

So here's whats going on. Once the PIR is warmed up it detects movement and increments the counter HOWEVER, the time it takes to detect the signal and pass this signal to the counter is far too long. If I wave my hand over the PIR there's about a 2-3 sec delay before the counter increments, then I have to wait a few seconds before I can wave my hand again for the PIR to detect.

Also, the sensor seems to be a little neurotic. Even though there's no movement it'll increment the counter. For now I'm willing to write that off as the PIR being to 'focused' which I'll address later. For now I want the circuit to respond faster.
I should also note, I used a NaPion/Panasonic PIR (much more expensive and smaller) and experienced similar results in 'lag'.

I have no resistors, diodes or caps connected to the circuit, just 3 series AAA batteries going to a breadboard with the PIR and counter.

I'm not claiming to be an electronics expert (despite my degree from 4 years ago which I've not used :rolleyes: ) so please go easy on me. I just want to open up discussion and hopefully some constructive information will present itself.
 

Mikebits

Well-Known Member
3 AAA batteries is only 4.5 VDC assuming batteries are fully charged. Spec sheet for your PIR list 4.7 VDC minimum, so that is one problem.
 

Reloadron

Well-Known Member
Most Helpful Member
First as Mike mentions make sure your power supply voltage exceeds the minimums.

So here's whats going on. Once the PIR is warmed up it detects movement and increments the counter HOWEVER, the time it takes to detect the signal and pass this signal to the counter is far too long. If I wave my hand over the PIR there's about a 2-3 sec delay before the counter increments, then I have to wait a few seconds before I can wave my hand again for the PIR to detect.

If you look at the data sheet for your PIR sensor you will note from the timing chart the output goes high on detection and remains high during detection. When detection stops the output remains high for about an additional 1/2 second.

You don't mention the exact version of the H7E totalizer you have but if you look at page 3 of the totalizer data sheet you will see the totalizer increments up one count when there is a logic low to high transition and the logic low is between zero and two volts and logic high is between 4.5 and 30 volts.

Given a choice with all of this I would likely use 4 EA. 1.5 batteries in a 6 volt pack. Some of the erratic problems should clear up. I would also output the PIR to a transistor and let the transistor drive the totalizer as shown on page 6 of the totalizer data sheet.

I have used a variety of small totalizers like this but never less their internal little lithium battery. I am not sure how using external power will work out with one of these units.

Ron
 

211

Member
Thanks Ron. That was helpful advice. I will modify my circuit tonight and follow up with the results.

Can I ask, what other totalizers have you used? The one I have is the H7EC-B. I scrounged this up at work but if I were to purchase one they're like 60 bucks! A little too expensive for what I'm doing with it. Once I get the basics of this circuit to work I plan on making a handful of these PIR Counters, assuming I can find inexpensive components.

BTW I've attached the datasheet for the H7EC-B counter. It's discontinued and is not the same as the counters in the original post but the characteristics are pretty much identical.
 

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Reloadron

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Before I forget, if you are in the US and want one or two more to play around with let me know. We use them in small test projects and names like Veeder Root and Reddington come to mind. My earlier post I did from work and there was a little Reddington lying on my desk. I also use much larger and expensive units made by Newport Instruments and Omega, I think Red Lion also comes to mind. Generally when a project is done or experiment the old panels and guts get tossed so I try to do my "rescue operations and remove guts I want to keep.

If you look at the last data sheet you linked to they also show a few NPN and PNP transistor driver configurations.

Tomorrow I need to be in the plant for a few hours and I can see what is lying around in my little junk piles. I am sure I should have some newer ones, newer meaning they were used maybe six months and not that old, maybe a tear or two so their batteries have plenty of time left.

Ron
 

211

Member
YES! I'd love to get my hands on as many of these as possible!
I sent a PM your way.

Thank You!
 

Reloadron

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Most Helpful Member
Got the PM and replied. I'll dig around tomorrow. No problem and I don't want anything. My Pleasure to help you out.

Ron
 

211

Member
I'm back to using the spot-type **broken link removed** (AMN43121) because the .5 second delay in the other PIR is a little too long. But now I'm back to the Panasonic being a little neurotic again.
I've got the output of the PIR connected to the counter input and also through an LED. The problem is, when I wave a hand over it, I get multiple output triggers (usually 3 in a row).

I've attached a drawing of the circuit I've configured on a breadboard. the counter I'm using is a no-voltage contact counter so all it needs to see is a pulse from the PIR output.

Can someone take a look at this circuit and tell me if I'm even on the right track?

Thanks- I've realized I suck at trying to build my own circuits from scratch so be patient with me please...
 

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Reloadron

Well-Known Member
Most Helpful Member
First, I have at least one small counter I'll be sending you. The Reddington that was on my desk for sure. Today if I have some time I'll try it with a few transistor drivers and see how well it works. They put things in an envelope and send them your way. Just want to be sure things work.

Next, based on what you are trying to do I am not sure a PIR sensor is the way to go. Possibly something like a photo sensitive transistor or LDR (Light Dependent Resistor) would be a better sensor choice. The problem you ar seeing now sounds like the sensor has a little bounce as it detects. Maybe false triggering. These things are hard to see without a device like an oscilloscope. PIR sensors are not fast responding devices.

Ron
 

211

Member
Ultimately this device will be used outdoors for extended periods of time. The circuit, counter and battery will be enclosed in a small weather resistant box while the pir will be on the end of a 6' cable. The PIR will be used to count human traffic along a park trail for consensus data. I've thought about a LDR but the range is usually shorter and if it's dark it wont trigger and if it's light, it may trigger on shadow movements and any other non-human movement.
I realize the PIR will trigger on any heat signature like deers or other animals but the ratio of animals vs. human traffic will be negligible over the course of a month.

Thanks for the counter(s) Ron, much appreciated!
 
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Reloadron

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Most Helpful Member
OK, one of these will be on the way tomorrow. Also some assorted transistors, I suggest you incorporate the transistor as a driver. Oh yeah, it's a 5300-1100 model. Note the settings in the data sheet to increment a count. Some on leading and some on trailing depending on settings. It should have years of battery remaining. Now I understand your application thanks. Should arrive in a padded envelope through the post office. From here to you...maybe a week at worst.

Ron
 
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