security

[Tim Lamb]

I am researching ways and means of adding outbuildings to my existing house burglar alarm.

The suppliers tell me there is a spare input so if I could common up the new signals all is simple.

However..... there are occasions when I need to access the outbuildings without wanting to turn off the house alarm. Is there a way of disabling the remote sensors locally? I have in mind a weatherproof keypad but I suppose a simple on/off keyswitch would do the same job. The keypad would have a greater deterrent effect of course.

Has anyone attempted this? I will need to involve the alarm installers for the final connections but don't want to pay their prices for 6 or more sets of local sensors.

regards

[Owain]

T'easiest way of doing this, especially if you have reliable mains power at the outbuildings, would be to given them their own alarm system with sirens etc, and take an auxiliary relay output from this to one zone of the house alarm.

This has the advantage that if the interconnect to the house fails (or is sabotaged) you can turn off that zone on the house system, but the outbuildings are still protected by their own alarm.

You can also have multiple zones at the outbuildings, all zoneable on or off at the outbuilding panel, in case you find false alarms from wind-rattled doors or rodent-activated PIRs.

Owain

[Tim Lamb]

In message , Owain writes

Power is fed from the farmhouse via buried ducts so it is easy to route signals back to the existing system. Presumably, if *open* is the alarm mode, switching off the remote power will not prevent the alarm sounding.

They would need a JCB:-)

Umm... It currently costs £50 per year to have the existing system maintained. I don't really want a second set of batteries needing changing or their operative spending more time on site. I think I could handle testing the external senders myself.

Rodents are not allowed on farms nowadays. PIR sensing range might be an issue though. 100' long x 45' wide eg. I don't think a reed switch and magnet makes much sense for 20' wide doorways, either. I envisage the remote sensing using mains voltage with a pair of relay contacts giving isolation for the existing. Maintenance safety might be an issue?

regards

[cj]

Hi Tim A simple zone isolator keyswitch should do what you reqire but as already posted a more secure way would be a stand alone system or if your existing alarm will accept it a radio expander.

HTH CJ

[Tim Lamb]

In message , cj writes

I think my first move must be to get the existing system engineer out to see what they can offer and explore what input signals are acceptable.

Existing remote operated garage doors will be an issue. I can't see my wife climbing out of her car to operate a keyswitch before pressing the zapper button and reversing the process burdened with shopping etc.

regards

[dom]

I tend to agree with the other posters, rather than make an existing system do something it wasn't really designed to do, get a separate system and interconnect it as necessary.

Presumably as you're only now considering protecting your outbuildings, you consider them less vulnerable or that a break-in less likely to result in a costly loss or damage?

If that's the case, get a diy system and fully install it yourself - no maintenance costs. If the outbuilding system is the slave of the house system, use a normally inactive signal on the outbuilding alarm such as "external sounder" connected to the coil of a normally closed relay contact - so that only "alarm" on the outbuilding system opens the relay contact (and not active/inactive/powerfail).

Would you want the possibility of a silent alarm (to the intruder in an outbuilding) ringing in the house? (so a posse of pitchfork wielding neighbours can be summoned)

Also sounds like motion sensors rather than door sensors are what's needed. Though I do like the idea of a Indiana Jones style traps.

[Tim Lamb]

In message , " [e-mail]" writes

Umm.

Most used farm machinery is not considered vulnerable to theft. The targets tend to be newish petrol driven portable stuff, ATV's and lawn tractors. Because the asset re-locators do not know which building will be most rewarding, they tend to look in them all with consequent damage.

Right.

If the house alarm is set, there are unlikely to be any pitchfork wielders about. Triggering the alarm would, hopefully, accelerate the villains departure.

I rather favour the welded angle iron *tank trap* designed to penetrate the driver's seat when closed gates are hit at speed:-(

regards

[SantaUK]

What type of panel do you have? The answer to this question, can make it a lot easier to advise.

[Tim Lamb]

In message , SantaUK writes

Umm... My geographical location is fairly easily found. Broadly it is an

8 way Aegis system. I believe the installing engineer said there was one spare input.

As yet I have not asked Aegis for advice so watch this space. They may veto it out of hand as being impractical.

regards

[SantaUK]

Sorry m8 never heard of Aegis

[Tim Lamb]

In message , SantaUK writes

Something discrete and local:-)

regards

[cj]

Hi as Tim I have never seen an Aegis panel but Aegis are a london based security company and may (as we do) have our company name printed on panels. Look here and see if yours looks like any of these.

[Tim Lamb]

In message , cj writes

Nothing similar. The control box is around 150mm square with no external switches or buttons. In view of likely anti-tamper arrangements, I am not about to unscrew the lid:-)

Currently spraining my brain trying to remember where I hid the original documentation!

regards

[cj]

Hi Tim You are looking at the dump box (system controll unit) You must have a remote keypad to operate the unit. Is it LCD or LED (coloured lights or a text display)?

Lokk at these;

afew of the common ones. If you can't find it try and describe the layout (especially any non-numeric keys) plus yes/no keys or A/B/C/D keys

HTH

CJ

[Tim Lamb]

In message , cj writes

star and hash plus ABCD

Display is a twin *8* pattern LED

My security system is still preventing me finding the bumpf left by the installer.

regards

[cj]

Hi Tim Sounds like an early Hilclaire panel (only one I recall with * # on keypad ) usually a metal unit about 4" x 5" with very neat raise keys and flush 2 seg 8 digit led display ABCD keys were seperate..from 12 keys of keypad. If i'm right hilclaire are long gone allong with all records of panels .I have a few mauals but in all honesty I would retire the panel if it is a Hilclaire.

Vague memories of an early Tunstall and chubb panel used by ADT having same keys but again all old series units.

If as your earlier post desribe you have easy access to the ducts and can also get cabling to the panel location it would seem easier to fit a new 16 zone panel using 2wire EOL wiring. These panels are not to expensive (starting around £65 c/w keypad)

HTH CJ

[Tim Lamb]

In message , cj writes

4x6.5" but otherwise yes. Nicely illuminated buttons.

I don't know what 2 wire EOL wiring is but the ducts are up to 50m long and contain 4 core steel wire armoured. If the alarm wiring is high impedance cross talk is likely?

regards

[dom]

Buy screened signal cable, slightly more expensive. Tie the screen at one end to earth. Your SWA also provides some screening of the live conductors.

If the cable runs are that long, it may make more sense to have 2 or more separate alarm systems, so that only a single signal cable is required between them - rather than one for each sensor.

[cj]

Hi Tim Sorry for technobabble. basically alarm wiring uses 2 cores for the zone and 2 cores for a tamper loop.(4 wire system) Newer systems use a single pair (2 wires)to monitor both tamper and zone activity. This is done either by a small 3 pin chip provided by the manufacturers or a combination of 2 resistors (again provided) The manufacturers recomend no more that 100m for any single run using std alarm cable. The resistor type systems are not bothered by crosstalk as they use a balanced line system whilst the chip type of panels are digital and again well suppressed. Remember we are dealing with short or open cct rather than a modulated carrier. so interference (whilst not impossible) is unlikely If you are drawing high currents through your mains cables and subject to high voltage swings then you could consider BT cable (being twisted pair) or even CAT5 network cable.

HTH

CJ

[Tim Lamb]

In message , " [e-mail]" writes

Back to where I started:-)

Each outbuilding has mains power.

A stand alone sensor system in each building could be used to operate a relay giving an alarm signal to the central system back in the house. The same relay could be used to give a bell signal when the house alarm is not set. Other than fault finding purposes it is not critical to know which system triggered the alarm.

regards