Wireless the way forward?

[lee2009]

just out of interest, on a wireless pir, do these still have wall tamper switches? so if i was to pull a wireless sensor off the wall would the alarm go off? what about if i at the same time removed the battery from one of these pirs?

 

[alumni]

just out of interest, on a wireless pir, do these still have wall tamper switches? so if i was to pull a wireless sensor off the wall would the alarm go off? what about if i at the same time removed the battery from one of these pirs?

Even the cheap nasty toot usually have dual tampers.
Decent kit, it's a given.

 

[joe-90]

dup

 

[joe-90]

Bernard. A standard wired siren unit won't tell you the strobe isn't working or the piezo siren - only that the tamper switch is closed. It's not uncommon to have a silent siren up there.

Some modern piezo drivers can routinely test that the element is functional with a very short chirp during which time the element's capacity and resonant frequency are checked. If these have changed the device is suspect. Whether this function is used ion alarms I do not know.

Also, a common problem with PIRs is that the relay contacts freeze in the closed position. It may look as if it's doing something but is in reality a complete ornament.

Any good panel relying on relay contacts will detect a stuck contact and report it as a fault.

Give me the name of a good panel that does that then.

And how does it test the strobe?

And which sounders self test the piezo?

 

[alumni]

Thought it was too good to be true.

Normal service resumed.

 

[bernardgreen]

Give me the name of a good panel that does that then.

I said some drivers that produce the voltage to drive the piezo element have the means to check the element is functional. I do not know which, if any, domestic alarm systems use them. I have seen them used in factory warning beacons where a failed warning system is notified to the control operator and, in some cases where the hazards justify it, the line is automatically shut down.

And how does it test the strobe?

With a photo sensitive diode.

And which sounders self test the piezo?

I am not going to turn on the other machine to look up manufacturers for you.

 

[joe-90]

Well none of them make alarm sirens that's for sure.

They are glorified door bells - nothing clever about them.

 

[sparkymarka]

well i know mines ok because i use bell squawk on arming. lol

 

[AssociatedAlarm]

They are glorified door bells - nothing clever about them.

Never seen a door bell detect someone on the path let alone the back 1st floor window.
Then call the ARC or home owner.

You sure your on the right subject here?

 

[joe-90]

Yup.

 

[bernardgreen]

They are glorified door bells - nothing clever about them.

Wireless ones maybe, not much point in them being anything else really. But alarm sirens connected to the panel by a cable are a different matter. Two way communication over a secure and protected link so they can report problems to the panel to alert the owner of problems. Unlike the majority of wireless sirens which have to cry for help and hope someone reacts before the battery goes flat and with it the ability to cry for a new one.

 

[bernardgreen]

Are PIR sensors on a wireless system compromised by the need to operate on minimum power in order to extend the useful life of a set of batteries.

With a wired alarm system the sensors have an adequate supply of power which means they do not need to employ any power saving methods. Wireless systems that depend on batteries almost certainly have to use power saving methods to obtain a reasonable battery life. ( Has anyone got the data for how much power a wireless PIR sensor uses compared to a wired PIR sensor ).

Could a wireless PIR sensor be compromised by having to be a low power device. If so how serious is the compromise and what does it affect ?

Does the sensor operate continuously or does it turn itself on and off to reduce power. Maybe it is active for only 1/4 of a second and inactive for the other 3/4 of a second. Or maybe 1/8 and 7/8. Do any of the advocates of wireless systems have the answers to these questions and can post them them here ?

I am sure wired PIR sensors are active all the time.

 

[joe-90]

They are glorified door bells - nothing clever about them.

Wireless ones maybe, not much point in them being anything else really. But alarm sirens connected to the panel by a cable are a different matter. Two way communication over a secure and protected link so they can report problems to the panel to alert the owner of problems. Unlike the majority of wireless sirens which have to cry for help and hope someone reacts before the battery goes flat and with it the ability to cry for a new one.

You obviously aren't an alarm engineer Bernard. They have a tamper switch - that's as good as it gets.

 

[bernardgreen]

You obviously aren't an alarm engineer Bernard. They have a tamper switch - that's as good as it gets.

On the first point you are correct,

On the second point I would disagree. Maybe that's as good as it gets in the majority of systems but I know one system where the state of the bell box battery is reported back to the panel. But that is in a commercial premises and was installed by a professional company.

 

[josh451]

( Has anyone got the data for how much power a wireless PIR sensor uses compared to a wired PIR sensor ).

Wireless PIR (ESP INFINTE)

Untitled

• josh451
• 14 May 2012
• 1

Wired PIR (TEXECOM PREMIER ELITE)

Untitled

• josh451
• 14 May 2012
• 1