Radio signal as an alternative to wall chipping, trenches and hanging wires

I belong to those summer residents who build their house without a well-developed project, as far as their own strength and financing. Hello friends in misfortune! Probably it will be interesting to the owners of apartments, with a complete repair. As a fact: the house is standing, almost finished, you can live ... but all sorts of "Wishlist" begin to come out, which are not provided or too lazy to do at an earlier stage. It will be about convenient control of light (or other electrical appliances). True, you want the switch to be in a convenient place !? And even better is a “remote control” that can lie next to the sofa ... The essence of the problem: the electricity in the house and the plot is somehow divorced. But it turns out that to turn on or turn off the light on the edge of the site, you need to go to the switch, which is located there. I decided to simplify my life.


The first causative agent of technical thought was the grill area. Electricity was supplied to it immediately from the meter on the pole, from it the power cable goes to the house underground (the requirement of the wife who did not accept the overhead line). When electrifying the site, it seemed logical not to pull the cable from the house along the new trench, but to take 220 volts from the nearest source. As a result, the switch remained attached to the site. Note that you forgot to turn off the light, you can only from the window 2 floors, and then dress - go outside, or the light will remain on all night. Here is a video that shows the situation "on the ground"



And as is clear from the video, I chose the best for myself, namely the parallel remote control system at a frequency of 433 MHz, which we “invented” in Master Kit shortly before for a little other project. The highlight of this system is that each channel works independently of the other. While the traditional remote control with a key fob or remote control get lost, while pressing the buttons.

The main module of the system - the transmitter has the article MP3329 SE
(Fig. To the right)
The radio channel is made on the popular RFM-12 radio module with frequency modulation, which improves the quality and reliability of communication. The range of stable operation was tested empirically: about 100 m in open area when using antennas in the form of a piece of wire. This range can be slightly increased if you install a remote antenna with an additional gain, for example, this . There is space for the corresponding connector on the transmitter. Additionally, feedback has been introduced into the logic of operation to increase the reliability of the entire system. That is, the transmitter, after sending the command to the executive relay, waits for a response from it and, if it is not there, makes two more similar attempts. If, in this case, no answer comes, then an alarm occurs on a separate line.

A small digression ... We developed the MP3329SE system for wireless repeaters of brake lights and turn signals for transport trolleys that are assembled in a road train and moving along the airfield. Lights with actuating relays and their own batteries with magnets are mounted on the extreme trolley and receive braking and cornering signals from the tractor via a radio channel. If the flashlight is lost or the battery is discharged, the driver receives a warning signal. When some trolleys are put under loading, the lights are transferred by the driver to the extreme trolley of an already loaded train, ready for movement. Etc. I’ll tell you more about this in another article and video ...

So, from the airfield we return to the cottage and its coverage.

To power the entire system, both the transmitter and the executive relays, 12-15 volts DC are used. Perhaps there is some inconvenience in this, that an additional power source is required, however, it is much safer than capacitor power supplies, which are widely used in conventional remote controls. You will install them with your own hands, therefore it is better not to risk with galvanically not isolated current sources. And picking up a source is not so difficult, any network adapters that often lie in the pantry as a legacy from old electronics will do. I did just that, to save space, I removed the plastic case by removing the power supply board itself.

The same 12 volts are used to supply a control signal to the inputs of the transmitter. The logic is simple, applied 12 Volts to the transmitter input - the executive relay turned on, removed the voltage - the relay turned off. Accordingly, if you use a conventional switch, the relay relay remains on while the switch is in the on position. If you control with the button, the relay is on while you hold the button pressed.

Now more about executive relays. There are 3 options. On one channel , two and six

Single-channel and two-channel relays, in addition to radio control, have outputs for local control with a button, which is very convenient. You can also use these conclusions to connect limit switches or safety sensors if you have to do anything to control moving objects such as gates, barriers, doors, transoms for ventilating the greenhouse.
In the case of pump control, a level sensor, such as a float switch, can be connected to these outputs. It will protect the tank from overflow.

The six-channel relay is suitable for the case when the power wires to the electrical systems diverge from one place, for example, from an electrical panel. This module can be placed in a plastic case, which can be purchased separately .

In addition to the transmitter and executive relays, a small remote control for 4 buttons for controlling single and dual channel relays can be introduced into the system . If you connect the remote control to a six-channel relay, the first 4 channels will be controlled.

The number of connected remotes, transmitters and relays must be said separately. MP3329SE transmitter memory can store up to 255 actuators. Thus, with each channel of the transmitter, you can connect a dozen executive relays that will work in parallel, or replace each other. As it is done in the repeaters of stoplights. While one set of lights on charge - the second one works, then they change.
The memory of each relay is designed for 30 control devices (remote control or transmitter) That is, one relay can be controlled from several places in the equipped area, several transmitters.

So, the remote control MP3329SE is designed for stationary installation and works on the principle of "radio cable". That is, instead of laying the cable, you can establish a radio channel.
The capabilities of the system can be increased as needed using various actuators. The appetite, as you know, comes with food ... You
can still control without using the radio channel using the local switch located next to your appliance.

So before embarking on a shovel for laying a cable or a punch, planning to drill or drill a wall, remember the wonderful radio waves that can pass through the walls. As the chief says: “No noise and dust.”

Interested in !? Here are two more series of videos:


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