How To Choose Between The Different Types Of Intruder Detection System

There are many different intruder detection systems on the market today which are claimed to be suitable protection against intruders. But making the right decision about which system is appropriate for any given property type is not easy, so we must approach it in a structured and logical way.

First, it is necessary to evaluate the types of system which are currently available. We can begin by investigating and comparing the two types of installation – wired and wireless:

Wireless sensors

1. The distance between the sensors and the control unit is limited and depends on the number and thickness of walls. Too many walls can block the signals, especially if the walls are thick.

2. The signals weaken and the sensor can generate false alarms as the battery power diminishes.

3. The number of sensors is limited, the more sensors the higher the probability of signals interfering with each other and not reaching the control panel.

4. The reliability is much lower because they use only 1 technique - passive infrared.

5. It is possible to walk freely inside the protected house wearing a thermal suit or using a powerful transmitter to block the weak detector signals.

6. More maintenance is required. There is also the risk that the battery will discharge completely if the property is left unattended during a prolonged absence.


Wired sensors

1. Distance is irrelevant. The number and thickness of walls between the sensors and the control unit does not affect the functionality.

2. There are no batteries to worry about.

3. There is no signal interference as the sensors communicate directly with the controller along the wires. Any number of sensors can be used.

4. There is no problem with reliability as these sensors use double technology.

5. It is impossible to move in the range of a sensor without being detected as it uses microwave technology as well as infrared to detect movement.

6. No maintenance is required at all.

From these comparisons, we can see that there can never be a 100% certainty that the signals from wireless detectors will reach the control panel, and that wireless systems are more of a liability than an asset. This draws us to the conclusion that the benefits of a wired system far outweigh the disadvantages of a wireless system.

Now we can advance to the next stage, which is comparing the types of wired systems.

Basically, there are two systems to compare: traditionally wired systems or the more modern “bus” system. It is called a bus system because it carries far more data than a conventional system. We must now compare these two wiring systems.

Wired vs Bus System
Multi cable

The bus system can be compared with a bus travelling on the road carrying many passengers each of whom has varying degrees of knowledge (“data”), and the conventional system can be compared with a car carrying only one occupant who has only his own “data”.

So one vehicle is carrying lots of data, and the other carries a very limited amount of data, but they are both doing the same thing – carrying that data to another location. We know that many cars are needed to match the amount of passengers (data) that the bus can carry.

Multi cable

Now lets say that the data being carried by each of the bus passengers and the car occupant is the data or signal from a sensor device - one passenger/occupant carries one signal from one device, and we can see that the bus can carry far more data from the sensors than the car can. The car carries the signal from only one device whereas the bus carries signals from many devices.

If we refer to the bus as the bus system, and the car as the conventional system, it becomes obvious that the conventional system needs far more cables than the bus system to carry the same amount of data. In the conventional system, each device has to be connected individually to the controller (many cars = many cables), but in the bus system there is only one cable (1 bus) connecting all the devices to the controller.


We now know that in a conventional system every device needs to be wired separately to the control panel, so imagine a large villa, condominium or hotel with many rooms - hundreds of cables and large and expensive plastic conduits are needed in the conventional system, which is complex and confusing for electricians and installation engineers, and mistakes can easily occur.

The bus system requires only one cable. Yes, just ONE cable, which is routed to each room, or each room in each house in the case of a resort, and this saves a huge amount in expenditure on cabling, conduits and labor, not to mention the nightmares created for the electricians!

The biggest disadvantage of the conventional system is the missing flexibility. If later on the owner wants to install an extra sensor, or needs additional fire protection, or the air-conditioning needs to be controlled at the reception desk of a hotel… new cables would have to be installed which is extremely difficult to achieve and major disruption could be caused. These problems just do NOT exist with the bus system as it is easy and quick to adapt and expand.

So we can come to the conclusion that the bus system is the most efficient and cost-effective solution for an installation encompassing intruder detection, fire detection, full automation, access control, etc.

So what happens in practice?

A miniature (60 * 38 mm) control board is installed in each room and this is connected to a single high speed digital bus cable to the main control unit.

Mini board

Several inputs and outputs make it possible to:

  • add motion sensors and/or fire sensors
  • sound warning devices such as sirens and beepers
  • activate electric locks to open doors
  • connect 2 proximity card/key readers

The board communicates by RS485 at a high speed over long distances.

Each room connects to the single bus cable and this is the only cable which connects to the controller.

What else can it do?

When you have a bus system installed you can use it to control almost any electrical appliance.

For instance, you can extend your intruder protection to include your boundary or perimeter by installing infrared “fences” which, when connected to the bus system, will activate your alarm system if the beams are broken.

Access control is a common use of the bus system. This allows key/card/tag-holders to enter or leave through controlled doors/gates/barriers by placing their card or key/card/tag close to a proximity reader. This is also useful for recording time and attendance for employees.

You could also control your interior and exterior lighting from the comfort of your armchair.

Controlling your air-conditioning system is another possibility.

You could even unlock a door for a visitor without getting up!

In fact, just about anything can be controlled using the bus system and it saves space and wiring, making it the perfect solution for large villas and houses, condominiums, hotels and resorts.

So, we recommend this system to our customers because it is quick and easy to install, will save you a fortune in parts and labor, can be extended easily, and no more nightmares!

Please contact us for any additional information

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