Terraced house alarm system

[streaker99]

Or when the door or window was closed but was seen by the system as being open due to a defective sensor which, being defective, would not detect the door or window being opened by an intruder.

Even YaleGuy3 recognised this as a weakness of the system he promoted.

But a defective sensor shows up as a fault on the system.

If the sensor is no longer communicating with the panel a fault condition occurs and the orange fault light comes on , you get a warning beep every thirty seconds and a message on the LCD screen warning that the 'lounge' 'kitchen' 'front window' or whatever you have named your device has dropped from the system.

The system has adequate safeguards to protect a domestic property.

Not only that but you would always do a risk assesment based on protecting the property in the circumstance that door or window sensors had not activated due to the fact they can be circumnavigated by smasshing the window or breaking through the door without opening it and movement sensors would be in sufficient number and placement to allow for such possibilities.

 

[bernardgreen]

But a defective sensor shows up as a fault on the system. If the sensor is no longer communicating with the panel a fault condition occurs

True... if the sensor cannot transmit or the panel cannot receive the signal from the sensor then a time out function in the panel will after some time detect loss of communication from that sensor.

But that is only one way that a sensor can be defective.

Just accept the fact that at the time the system is set the panel has no way of knowing if a critical door or window is open. It assumes the door or window is shut and allows the user to set the alarm without giving any indication to the user that one or more doors or windows are both not protected.

This is a defect in the system, a defect that is un-avoidable when the system is low cost and due to that low cost requirement uses one way wireless communication that complies with the regulations imposed on manufacturers of licence exempt radio transmitters.

 

[bernardgreen]

duplicate deleted

 

[streaker99]

Bernard you are correct on a technical point but as mentioned in your risk assesment you allow for those eventualities.

I know someone who had a yale alarm premium installed that did everything they wanted for £475 including five pirs , four contacts and an extra working siren. They had also bee quoted £2000 by a pro installer for a non monitored system.

If I could save £1500 for the sake of just checking my doors and windows are shut (which is something I do now anyway as most pro installs dont even have door and window contacts just pirs) then I would.

You are looking at minor issues and trying to turn them into dealbreakers.

 

[peaps2]

I can disable any wireless system with ease. Two houses near my house (nearest 200m other 600m) are knocked out by my radio equipment.... Regular false alarms etc RFI/ECM is a problem.

 

[streaker99]

I can disable any wireless system with ease. Two houses near my house (nearest 200m other 600m) are knocked out by my radio equipment.... Regular false alarms etc RFI/ECM is a problem.

The systems can be set to ignore inteference for example when someone closeby is a radio ham

Do you have a licence?

 

[bernardgreen]

The systems can be set to ignore inteference for example when someone closeby is a radio ham

WRONG
No radio receiver can be set to ignore interference. If there is a signal on frequency or strong enough to break through the receiver's tuning then the receiver and the system it is connected to will be affected.

What can be set is the reaction of the system to interference.

Some systems can only respond by sounding the main external alarm siren when signals from an external source are blocking the system's receivers.

Other systems will change frequency to find a clear channel and if that is not sucessful they will often issue an urgent warning before going into full alarm state.

 

[Workers]

Even some of the latest RF equipment with 90 channel hopping CAN be blown out by a "Ham" nearby.


As for the other question Visonic WILL not allow a window or door with a contact left open to set. Unless of course you tell it to. Unlike the other system mentioned here.

http://www.e-fireandsecurity.co.uk/visonic/b1

 

[ckl139]

Thanks for the link...but I looked a bit deeper to this page - which is suggested for DIY?

http://www.e-fireandsecurity.co.uk/visonic-powermax-alarms/c2



So this one would be better than the Yale I originally linked.

Folks - please can we keep to the topic - appreciate its a good debate but one that has digressed from my OP.

 

[streaker99]

I think the obvious solution here is dont choose wireless if you live near a radio Ham.

On another note regarding wireless.

I had preprogrammed a wireless transmitter to install and when I had the control panel in my hand my car remote would not operate the central locking. When the control panel was moved about three metres away then the central locking worked fine again.

The point being as with wifi routers etc they have to be very close to the control panel ie less than a metre before they cause problems , although in this case it was not the control panel compromised by the central locking but vica verca.

 

[bernardgreen]

when I had the control panel in my hand my car remote would not operate the central locking. When the control panel was moved about three metres away then the central locking worked fine again.

That suggests the transmitter in the panel may have been transmitting almost continuously which may be operation in contravention of the time limits set in the condition for licence exempt equipment of the type the panel was part of.

In some applications the transmitters are restricted to less than 1% of the time. This is to ensure receivers on other systems ( such as car central locking ) are not permanently blocked by transmissions from other systems.

Some bedtime reading for those who want or need to know the conditions imposed on licence exempt radio equipment.

http://stakeholders.ofcom.org.uk/bi...-tech-info/interface-requirements/IR_2030.pdf

 

[peaps2]

I can disable any wireless system with ease. Two houses near my house (nearest 200m other 600m) are knocked out by my radio equipment.... Regular false alarms etc RFI/ECM is a problem.

The systems can be set to ignore inteference for example when someone closeby is a radio ham

Do you have a licence?

Utter rubbish.

Yes I do have a licence.

 

[peaps2]

I think the obvious solution here is dont choose wireless if you live near a radio Ham.

On another note regarding wireless.

I had preprogrammed a wireless transmitter to install and when I had the control panel in my hand my car remote would not operate the central locking. When the control panel was moved about three metres away then the central locking worked fine again.

The point being as with wifi routers etc they have to be very close to the control panel ie less than a metre before they cause problems , although in this case it was not the control panel compromised by the central locking but vica verca.

WIFI is very low level RF, ANY receiver can fall foul of front end overload.

 

[peaps2]

The systems can be set to ignore inteference for example when someone closeby is a radio ham

WRONG
No radio receiver can be set to ignore interference. If there is a signal on frequency or strong enough to break through the receiver's tuning then the receiver and the system it is connected to will be affected.

What can be set is the reaction of the system to interference.

Some systems can only respond by sounding the main external alarm siren when signals from an external source are blocking the system's receivers.

Other systems will change frequency to find a clear channel and if that is not sucessful they will often issue an urgent warning before going into full alarm state.

Spurious emissions (direct harmonics) are also a problem.

 

[streaker99]

I can disable any wireless system with ease. Two houses near my house (nearest 200m other 600m) are knocked out by my radio equipment.... Regular false alarms etc RFI/ECM is a problem.

The systems can be set to ignore inteference for example when someone closeby is a radio ham

Do you have a licence?

Utter rubbish.

Yes I do have a licence.

I think we have stumbled into a pedantic argument over the definition of the word ignore.

To both Bernard and yourself..

ig·nore Listen to audio/ɪgˈnoɚ/ verb
ig·nores; ig·nored; ig·nor·ing
[+ obj] 1 : to refuse to show that you hear or see (something or someone)
▪ She tried to ignore him but he wouldn't leave her alone. ▪ I'll ignore that last remark.
2 : to do nothing about or in response to (something or someone)
▪ If we continue to ignore these problems they will only get worse. ▪ They ignored the warning signs. ▪ ignoring the poor


In the case of the Yale siren if it detects a frequency that is transmitting on its own frequency within set parameters of duration and frequency the siren will activate assuming the system is being deliberately jammed.
If you alter one of the dip switches in the siren the under the same circumstances the siren will NOT activate because you have set the siren to IGNORE the inteference as per definition 2.

oh my lord English lessons to adults...