The presence sensor or motion detector is a device that captures the movement of people in its radius of action and activates or deactivates, generally, a lighting system.
- Presence sensor
- Phase, neutral and ground cables
- Lamp, if it is a new installation
- Dowels and screws
- Channels for cables
- Wire strippers
Plan the work and calculate the material
The presence sensors are very simple devices to install, and their uses are multiple: it illuminates rooms only when they are occupied, which allows you to save on electricity consumption; It connects with the presence of strangers in your garden, surprising them with lighting; It facilitates access to your home if you arrive at night, joining the entrance light. You can regulate the lighting time of the lamps that are connected to it using its timer, select the operating hours, and regulate the range.
Think about where in the house, you will install the sensor or sensors to cover the necessary scope and orientation. Another aspect to keep in mind is if you are going to place them on the ceiling or walls or if you want to embed them.
The use is another key; for a corridor, you need less angle of detection than necessary for the outside, for example. If the detector is going to be outside the house, buy one with a high degree of IP protection. Calculate the wiring you need and the gutters, if the cable is going to be hidden in them.
How do they work
The sensors usually work by infrared and detect, in their area of action, the passage of people. When this happens, the mechanism of operation of the device is activated, as programmed.
Although it is usual to connect the presence detectors to a lamp or lamps to illuminate the passage, they can also connect to a fan, an air conditioning system, or an alarm. In this way, energy is saved since the devices only work when necessary.
Where to place it
Place the detector at a minimum height of 2.5 meters. In any case, follow the manufacturer’s recommendations. It can go on the ceiling or the wall, always in the place that allows you to cover a greater angle of detection.
The electrical connection
The connection of the lamp with the sensor and the latter with the current input is made using terminals that the device itself incorporates.
The PIR sensor (infrared) has two terminals with phase or line cables (brown and black), one for power supply and one for output to the lamp, and a neutral terminal (blue color). Phase, impartial, and earth wires from the junction box must be supplied to the airport.
At the same time, the phase, neutral, and earth wires must be routed to the lamp: if the lamp to be lit was near, these three wires could be those coming from the lamp.
Where to take the cables
To carry cables from the junction box to the sensor and connect it to the lamp, you can use, if possible, the existing recessed channel. The junction box and the light are joined by a corrugated tube, through which you can pass the necessary cables. From the lamp or the package, you have to carry the wires or a false ceiling or by chases from the box or with cable ducts. Before undertaking the work, think if you have any installation or disused wiring that you can cancel to use it for the sensor.
Step by Step
1. Sketch where the sensors will go
Make a presentation of the place where you are going to place the motion detector. Think about the electrical connections you have to make: take energy from a junction box and carry wires to the lamp or lamps in line you want to be lit with the sensor.
2. Make the electrical extension
According to the assembly scheme of the mechanism. You must take power to the device from a junction box and connect the sensor to the lamp with the necessary cables. Take advantage of spaces or existing holes as false ceilings.
3. Pass the cables with the help of the guide
Before starting to install the sensor, you must have the cables necessary for its operation, according to the assembly diagram. Take the wires with a guide, if they are hidden or through gutters.
4. Disassemble the mechanism
Place your box on the wall or ceiling and mark the position where you will place the sensor.
5. Make holes for fixing
Drill and place the studs flush with the wall or ceiling.
6. Fix the box
Screw the cassette or frame of the machine to the support.
7. Cut off the electric light
Cut off the electricity tap in the main panel before starting to make electrical connections to the junction box, lamp, and device.
8. Make the electrical connection in the device
Do not forget to run the cables through the rubber gasket of the machine before connecting them.
9. Mount the sensor
Reassemble the sensor to the box and screw.
10. Make the necessary connections in the lamp
If it was a lamp with a transformer, like some built-in halogens, it makes the connections in the transformer.
11. Make all other connections
Make also the connections in the derivation box.
You must read the characteristics of the presence sensor well to know the capacity of illumination that it admits. This is important if you have several lamps installed online, so there is no overload.
12. Regulates the sensor
Regulate in the device the functions of both the timer and the periods in which you want it to work (all day or only at night, for example).
13. Check the operation of the sensor
Open the power step switch in the general frame and check its operation. It regulates the orientation of the device, according to the scope and situation of the space.