Look at the floor of any caravan and you will find ventilation holes covered only with a fine mesh - absolutely no deterrent to the determined insect.  Once inside the spider can cause havoc with sensors which rely on the detection of heat or motion.  Even the wind blowing a tree can affect PIR sensors which ‘see’ the change in light and heat as the tree’s branches wave above the skylight.  Much can be done by closing the blind over the roof-light, but can we really expect every owner to remember every time the caravan is left unattended?

Caravans are designed to give the owners a light, airy interior with views of the countryside from all seating areas - in the latest models most of the ceiling is also transparent.  PIR sensors must be especially designed to cope with the small range inside those windows without being ‘confused’ by changes outside the windows.

Vibration is a factor which must be considered carefully.  Whenever a caravan is in motion, vibration will be present - but the motion caused by wind or passing vehicles must not be confused with the vibration of towing.  The movement of people inside the caravan will give rise to vibration and/or bumps, some of which, particularly when setting the caravan up for the night, might be violent enough to cause false alarms.

Tilt sensors are not as good as they seem at first because they have to be re-calibrated to the true vertical, every time the caravan is sited.  Not a task most owners will undertake willingly, given that the sensor will be positioned near to the wheel - ie under a bunk somewhere.

The only power supply is a 12v leisure battery, and insects have easy access to the interior, causing false alarms to systems which rely on PIR.

Lifestyle Considerations
A caravan is designed to attach easily to a vehicle, and to be moved from place to place.  The owner needs security not only whilst the vehicle is in storage, but also whilst in transit.

Caravanners are sociable people, often gathering for impromptu barbeques, hidden behind windbreaks, leaving the caravans vulnerable to the opportunist thief.  The alarm should protect vulnerable equipment.

Many owners use their caravans only during the summer months, with the caravan being stored over winter.  The alarm must not drain the battery.

A significant proportion of owners are over fifty, with many having taken early retirement to enjoy the freedom of caravanning both in the UK and Europe.  Yet another PIN number to remember is not attractive.

Caravan owners return to their vans at night.  It is very difficult to open the door, find the light switch and enter a code on a keypad before the conventional alarm is triggered.

Travelling through Europe, and increasingly in this country, the owner is at risk from intruders at night, when held up in towns and cities and on the approaches to the Channel crossing points.  An alarm must be flexible enough to offer protection at all times.

Scanner technology has reduced the security of the remote systems dramatically.  It is now all too easy for the would-be thief to capture the broadcast ‘message’ between key and vehicle and to reproduce that code in the absence of the legal owner.

The interior of a caravan is small, reducing the arc available to a PIR system, usually leaving significant areas unprotected.

Wireless systems have proven themselves unreliable in this environment as they are prone to signals from neighbouring caravans, triggering false alarms.

Alarm systems from Farsite Products have taken all these factors into account, to be as simple to operate and as reliable as possible in this environment