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Default PIR interfering with wireless network

We have a wireless network at work which appears to have gone downhill since the workmen installed PIRs for the burglar alarm. One of them in particular appears to cause dropped packets the closer a laptop is to it. Is this possible?? It's not a wireless PIR as far as I know, as I can see some leftover cable he was using which is a multicore (about 10 cores) type similar to phone systems, so I assume this is for the signal aswell as power. The person in that office swears blind that there were absolutely no problems until the PIR was installed above her desk, and now when I check, about 60% of the packets are being dropped. Moving her laptop to the opposite side of the room it drops only 5% of packets. PIRs used to just pick up infrared of your bodyheat, but I think now they are also motion sensors? Perhaps this means they are sending out a signal and bouncing it off you? Perhaps this could interfere with wireless networking?

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Default PIR interfering with wireless network

On Fri, 30 Jan 2009 18:20:10 -0000, "Peter Hucker"
wrote:

We have a wireless network at work which appears to have gone downhill
since the workmen installed PIRs for the burglar alarm. One of them in
particular appears to cause dropped packets the closer a laptop is to
it. Is this possible?? It's not a wireless PIR as far as I know, as I
can see some leftover cable he was using which is a multicore (about 10
cores) type similar to phone systems, so I assume this is for the signal
aswell as power. The person in that office swears blind that there were
absolutely no problems until the PIR was installed above her desk, and
now when I check, about 60% of the packets are being dropped. Moving
her laptop to the opposite side of the room it drops only 5% of packets.
PIRs used to just pick up infrared of your bodyheat, but I think now
they are also motion sensors? Perhaps this means they are sending out a
signal and bouncing it off you? Perhaps this could interfere with
wireless networking?

---
If its PIR it shouln't.

PIR is Passive Infra Red, and it's body heat which triggers the sensor,
not anthing the device transmits.

http://www.glolab.com./pirparts/pirmanual.PDF

Maybe the wiring is affecting the strength of the RF field areound where
she sits.

JF
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Default PIR interfering with wireless network

On Fri, 30 Jan 2009 20:18:14 -0000, John Fields wrote:

On Fri, 30 Jan 2009 18:20:10 -0000, "Peter Hucker"
wrote:

We have a wireless network at work which appears to have gone downhill
since the workmen installed PIRs for the burglar alarm. One of them in
particular appears to cause dropped packets the closer a laptop is to
it. Is this possible?? It's not a wireless PIR as far as I know, as I
can see some leftover cable he was using which is a multicore (about 10
cores) type similar to phone systems, so I assume this is for the signal
aswell as power. The person in that office swears blind that there were
absolutely no problems until the PIR was installed above her desk, and
now when I check, about 60% of the packets are being dropped. Moving
her laptop to the opposite side of the room it drops only 5% of packets.
PIRs used to just pick up infrared of your bodyheat, but I think now
they are also motion sensors? Perhaps this means they are sending out a
signal and bouncing it off you? Perhaps this could interfere with
wireless networking?

---
If its PIR it shouln't.

PIR is Passive Infra Red, and it's body heat which triggers the sensor,
not anthing the device transmits.

http://www.glolab.com./pirparts/pirmanual.PDF


I'm not sure if it's PIR or not. Aren't a lot of them nowadays multifunction?

Maybe the wiring is affecting the strength of the RF field areound where
she sits.


The wiring? It shouldn't have that strong a field from its wiring surely?

The effect is as such: within about 2-3 metres the network is unusable. The next 2-3 metres it works most of the time. After that it's almost perfect.

--
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But, if you had purchased $1,000.00 worth of Beer one year ago, drank all the beer, then turned in the cans for the aluminium recycling refund, you would have had $214.00.
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Default PIR interfering with wireless network

On Fri, 30 Jan 2009 20:44:44 -0000, "Peter Hucker"
wrote:

On Fri, 30 Jan 2009 20:18:14 -0000, John Fields wrote:

On Fri, 30 Jan 2009 18:20:10 -0000, "Peter Hucker"
wrote:

We have a wireless network at work which appears to have gone downhill
since the workmen installed PIRs for the burglar alarm. One of them in
particular appears to cause dropped packets the closer a laptop is to
it. Is this possible?? It's not a wireless PIR as far as I know, as I
can see some leftover cable he was using which is a multicore (about 10
cores) type similar to phone systems, so I assume this is for the signal
aswell as power. The person in that office swears blind that there were
absolutely no problems until the PIR was installed above her desk, and
now when I check, about 60% of the packets are being dropped. Moving
her laptop to the opposite side of the room it drops only 5% of packets.
PIRs used to just pick up infrared of your bodyheat, but I think now
they are also motion sensors? Perhaps this means they are sending out a
signal and bouncing it off you? Perhaps this could interfere with
wireless networking?

---
If its PIR it shouln't.

PIR is Passive Infra Red, and it's body heat which triggers the sensor,
not anthing the device transmits.

http://www.glolab.com./pirparts/pirmanual.PDF


I'm not sure if it's PIR or not. Aren't a lot of them nowadays multifunction?


---
Dunno; you were the one who tagged it as PIR.
---


Maybe the wiring is affecting the strength of the RF field areound where
she sits.


The wiring? It shouldn't have that strong a field from its wiring surely?


---
I didn't say the wiring was responsible for generating the field, I said
it might have an _effect_ on the [already existing] field.

JF
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Default PIR interfering with wireless network

Ok, I have been reading this thread with great amusement. :-)

A couple of things to clear up. A PIR motion detector is a Passive Infrared
detector that detects movement in a space based upon focused infrared
temperature changes thru a Fresnel Lens of an object in front of the
detector. It cannot detect thru walls or glass.

A "Dual-Tech" Motion Detector uses two(dual) technologies to detect motion
or movement in a space. It uses a PIR sensor and a Microwave sensor. The
microwave sends out pulses of microwave energy into the space if the return
signals change due to a person/object moving in the space (or outside the
space because it can see thru walls) and there is a temperature change that
has been detected by the PIR at the same time there is an alarm. This is
less false alarm prone than the simple PIR.

All that being said the simple way to prove or disprove that the detector is
causing the problem is get the security tech to power down the panel and see
what happens.

My guess is that something else other than the detector is causing the
problem and it is just a coincidence that it happened at the same time of
the install. It would be my guess that one of the following is the cause.

1) The transceiver was moved from its original position and the range in
this area was modified.

2) Some metal object has been moved/placed at a point that is deflecting
the signal.

3) A fluorescent light bulb/ballast is failing and giving off massive
amount of RFI causing the interference.

4) Sun Spots are reaching a peak in your area.

5) The earth magnetic field has been modified in ways that cannot be
fully explained. i.e. Government Plot!!!

5) All of the above.

6) Other

I have used the KISS method in the above description to ease the pain.
Some error in wording may be found. Whoops!!! Sorry for any confusion.

Hope that helps you to find your problem. Wireless is never perfect.

Good luck and have a nice day.

Les













"John Fields" wrote in message
...
On Fri, 30 Jan 2009 20:44:44 -0000, "Peter Hucker"
wrote:

On Fri, 30 Jan 2009 20:18:14 -0000, John Fields
wrote:

On Fri, 30 Jan 2009 18:20:10 -0000, "Peter Hucker"
wrote:

We have a wireless network at work which appears to have gone downhill
since the workmen installed PIRs for the burglar alarm. One of them in
particular appears to cause dropped packets the closer a laptop is to
it. Is this possible?? It's not a wireless PIR as far as I know, as I
can see some leftover cable he was using which is a multicore (about 10
cores) type similar to phone systems, so I assume this is for the signal
aswell as power. The person in that office swears blind that there were
absolutely no problems until the PIR was installed above her desk, and
now when I check, about 60% of the packets are being dropped. Moving
her laptop to the opposite side of the room it drops only 5% of packets.
PIRs used to just pick up infrared of your bodyheat, but I think now
they are also motion sensors? Perhaps this means they are sending out a
signal and bouncing it off you? Perhaps this could interfere with
wireless networking?

---
If its PIR it shouln't.

PIR is Passive Infra Red, and it's body heat which triggers the sensor,
not anthing the device transmits.

http://www.glolab.com./pirparts/pirmanual.PDF


I'm not sure if it's PIR or not. Aren't a lot of them nowadays
multifunction?


---
Dunno; you were the one who tagged it as PIR.
---


Maybe the wiring is affecting the strength of the RF field areound where
she sits.


The wiring? It shouldn't have that strong a field from its wiring surely?


---
I didn't say the wiring was responsible for generating the field, I said
it might have an _effect_ on the [already existing] field.

JF





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Default PIR interfering with wireless network

I covered it with a biscuit tin lid today, and the problem immediately vanished. I happend to spot a workman installing more of them and told him to remove it. He said therew as absolutely no way it could be causing that problem, but I persuaded him to remove it while a continuous ping was on the screen of a wireless laptop. It could clearly be seen that as soon as he unplugged it, everything worked, and when he put it back, packets disappeared. He told me it used microwaves, but couldn't tell me the frequency (although he thought it was meant to be substantially higher than 2.4GHz). All of the detectors throughout the building look identical, but only this one appeared to cause problems. Perhaps it was faulty and was oscillating at half the correct frequency?

The whole of the new corridor still hates higher numbered channels for no apparent reason. Channel 1 works perfectly, channel 6 works with older laptops but not new ones(?!) and channel 11 works with nothing. There is only that one transmitter in range there, so who knows what's going on!


On Sat, 31 Jan 2009 16:56:24 -0000, ABLE1 wrote:

Ok, I have been reading this thread with great amusement. :-)

A couple of things to clear up. A PIR motion detector is a Passive Infrared
detector that detects movement in a space based upon focused infrared
temperature changes thru a Fresnel Lens of an object in front of the
detector. It cannot detect thru walls or glass.

A "Dual-Tech" Motion Detector uses two(dual) technologies to detect motion
or movement in a space. It uses a PIR sensor and a Microwave sensor. The
microwave sends out pulses of microwave energy into the space if the return
signals change due to a person/object moving in the space (or outside the
space because it can see thru walls) and there is a temperature change that
has been detected by the PIR at the same time there is an alarm. This is
less false alarm prone than the simple PIR.

All that being said the simple way to prove or disprove that the detector is
causing the problem is get the security tech to power down the panel and see
what happens.

My guess is that something else other than the detector is causing the
problem and it is just a coincidence that it happened at the same time of
the install. It would be my guess that one of the following is the cause.

1) The transceiver was moved from its original position and the range in
this area was modified.

2) Some metal object has been moved/placed at a point that is deflecting
the signal.

3) A fluorescent light bulb/ballast is failing and giving off massive
amount of RFI causing the interference.

4) Sun Spots are reaching a peak in your area.

5) The earth magnetic field has been modified in ways that cannot be
fully explained. i.e. Government Plot!!!

5) All of the above.

6) Other

I have used the KISS method in the above description to ease the pain.
Some error in wording may be found. Whoops!!! Sorry for any confusion.

Hope that helps you to find your problem. Wireless is never perfect.

Good luck and have a nice day.

Les













"John Fields" wrote in message
...
On Fri, 30 Jan 2009 20:44:44 -0000, "Peter Hucker"
wrote:

On Fri, 30 Jan 2009 20:18:14 -0000, John Fields
wrote:

On Fri, 30 Jan 2009 18:20:10 -0000, "Peter Hucker"
wrote:

We have a wireless network at work which appears to have gone downhill
since the workmen installed PIRs for the burglar alarm. One of them in
particular appears to cause dropped packets the closer a laptop is to
it. Is this possible?? It's not a wireless PIR as far as I know, as I
can see some leftover cable he was using which is a multicore (about 10
cores) type similar to phone systems, so I assume this is for the signal
aswell as power. The person in that office swears blind that there were
absolutely no problems until the PIR was installed above her desk, and
now when I check, about 60% of the packets are being dropped. Moving
her laptop to the opposite side of the room it drops only 5% of packets.
PIRs used to just pick up infrared of your bodyheat, but I think now
they are also motion sensors? Perhaps this means they are sending out a
signal and bouncing it off you? Perhaps this could interfere with
wireless networking?

---
If its PIR it shouln't.

PIR is Passive Infra Red, and it's body heat which triggers the sensor,
not anthing the device transmits.

http://www.glolab.com./pirparts/pirmanual.PDF

I'm not sure if it's PIR or not. Aren't a lot of them nowadays
multifunction?


---
Dunno; you were the one who tagged it as PIR.
---


Maybe the wiring is affecting the strength of the RF field areound where
she sits.

The wiring? It shouldn't have that strong a field from its wiring surely?


---
I didn't say the wiring was responsible for generating the field, I said
it might have an _effect_ on the [already existing] field.

JF







--
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Mouthwash.
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Default PIR interfering with wireless network

On Sat, 31 Jan 2009 15:07:06 -0000, John Fields wrote:

On Fri, 30 Jan 2009 20:44:44 -0000, "Peter Hucker"
wrote:

On Fri, 30 Jan 2009 20:18:14 -0000, John Fields wrote:

On Fri, 30 Jan 2009 18:20:10 -0000, "Peter Hucker"
wrote:

We have a wireless network at work which appears to have gone downhill
since the workmen installed PIRs for the burglar alarm. One of them in
particular appears to cause dropped packets the closer a laptop is to
it. Is this possible?? It's not a wireless PIR as far as I know, as I
can see some leftover cable he was using which is a multicore (about 10
cores) type similar to phone systems, so I assume this is for the signal
aswell as power. The person in that office swears blind that there were
absolutely no problems until the PIR was installed above her desk, and
now when I check, about 60% of the packets are being dropped. Moving
her laptop to the opposite side of the room it drops only 5% of packets.
PIRs used to just pick up infrared of your bodyheat, but I think now
they are also motion sensors? Perhaps this means they are sending out a
signal and bouncing it off you? Perhaps this could interfere with
wireless networking?

---
If its PIR it shouln't.

PIR is Passive Infra Red, and it's body heat which triggers the sensor,
not anthing the device transmits.

http://www.glolab.com./pirparts/pirmanual.PDF


I'm not sure if it's PIR or not. Aren't a lot of them nowadays multifunction?


---
Dunno; you were the one who tagged it as PIR.


Force of habit, as that's all they used to be.

--
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In a few moments, her voice rang out in the darkness: "Doctor, I've undressed. What shall I do with my clothes?"
"Put them on the chair, on top of mine."
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Default PIR interfering with wireless network

On Jan 31, 4:20 am, "Peter Hucker" wrote:
We have a wireless network at work which appears to have gone downhill since the workmen installed PIRs for the burglar alarm. One of them in particular appears to cause dropped packets the closer a laptop is to it. Is this possible?? It's not a wireless PIR as far as I know, as I can see some leftover cable he was using which is a multicore (about 10 cores) type similar to phone systems, so I assume this is for the signal aswell as power. The person in that office swears blind that there were absolutely no problems until the PIR was installed above her desk, and now when I check, about 60% of the packets are being dropped. Moving her laptop to the opposite side of the room it drops only 5% of packets. PIRs used to just pick up infrared of your bodyheat, but I think now they are also motion sensors? Perhaps this means they are sending out a signal and bouncing it off you? Perhaps this could interfere with wireless networking?



You can now get ones that use microwave detection as well as PIR, they
are called "Dual PIR" sensors:
http://www.ness.com.au/ViewProduct.a...Number=100-210
10.5GHz for the microwave

A normal PIR sensor would not cause any issues like this as they are
passive.

You can simply swap a Dual PIR for a normal PIR no probems. Sensors
only need a 4 conductor cable, two for power (12V), two for the
contact.

Dave.
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Default PIR interfering with wireless network

On Fri, 30 Jan 2009 21:29:33 -0000, David L. Jones wrote:

On Jan 31, 4:20 am, "Peter Hucker" wrote:
We have a wireless network at work which appears to have gone downhill since the workmen installed PIRs for the burglar alarm. One of them in particular appears to cause dropped packets the closer a laptop is to it. Is this possible?? It's not a wireless PIR as far as I know, as I can see some leftover cable he was using which is a multicore (about 10 cores) type similar to phone systems, so I assume this is for the signal aswell as power. The person in that office swears blind that there were absolutely no problems until the PIR was installed above her desk, and now when I check, about 60% of the packets are being dropped. Moving her laptop to the opposite side of the room it drops only 5% of packets. PIRs used to just pick up infrared of your bodyheat, but I think now they are also motion sensors? Perhaps this means they are sending out a signal and bouncing it off you? Perhaps this could interfere with wireless networking?



You can now get ones that use microwave detection as well as PIR, they
are called "Dual PIR" sensors:
http://www.ness.com.au/ViewProduct.a...Number=100-210
10.5GHz for the microwave

A normal PIR sensor would not cause any issues like this as they are
passive.

You can simply swap a Dual PIR for a normal PIR no probems.


Good point, I'll just tell them to put in a passive in any rooms with problems if I can prove it's that.

We've always had detectors though and never had problems, so maybe it's faulty? Or the new ones are on a different band. If it's using 2.4GHz, in my opinion it's wrong. Using the same band as wireless networks in an office is just plain stupid.

Sensors only need a 4 conductor cable, two for power (12V), two for the
contact.


Odd that they left a bit of approx 10 core cable then (and that was the only thing they were fitting at the time). Unless it uses a different core for each type of detection?

--
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Everyone in the bar is now staring at them. Naturally, the guy is hopelessly and completely embarrassed and he slinks back to his table.
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Default PIR interfering with wireless network

Peter Hucker wrote:
We have a wireless network at work which appears to have gone downhill since the workmen installed PIRs for the burglar alarm. One of them in particular appears to cause dropped packets the closer a laptop is to it. Is this possible?? It's not a wireless PIR as far as I know, as I can see some leftover cable he was using which is a multicore (about 10 cores) type similar to phone systems, so I assume this is for the signal aswell as power. The person in that office swears blind that there were absolutely no problems until the PIR was installed above her desk, and now when I check, about 60% of the packets are being dropped. Moving her laptop to the opposite side of the room it drops only 5% of packets. PIRs used to just pick up infrared of your bodyheat, but I think now they are also motion sensors? Perhaps this means they are sending out a signal and bouncing it off you? Perhaps this could interfere with wireless networking?


The IR sensor might be one of the dual sensor (expensive!) type that
also include a microwave T/R motion sensing circuit. That would be very
likely to interfere with wireless networking systems. The security
company should be able to tell you for sure.


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\|/ \|/ it is illegal to kill them." Perna condita delenda est
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