> For the complete documentation index, see [llms.txt](https://wiki.inels.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://wiki.inels.com/inels-home/inels-wireless/tutorial-8-range-and-repeaters.md).

# Tutorial 8: range and repeaters

Find out why a button works close to the unit but not from where you need it, and fix it with placement, an antenna, the repeater function or an RFRP-20N.

*Part 2 — Tutorials. Read* [*How programming works*](/inels-home/inels-wireless/how-programming-works.md) *first (the Range section).*

***

## What you will do

Make a radio link work reliably from the place where you will really use it.

|   | Step                        | You will learn                                     |
| - | --------------------------- | -------------------------------------------------- |
| 1 | Test where you will install | How to find a weak link before you wire everything |
| 2 | Fix it, cheapest first      | Placement, antenna, repeater function, RFRP-20N    |

## You need

* A paired controller and unit that work close together ([Tutorial 1](/inels-home/inels-wireless/tutorial-1-your-first-button-and-light.md))
* Possibly an **RFRP-20N** repeater, or an **AN-E / AN-E3** external antenna

## 1. Know the numbers

Range is up to **200 m in open space**. Some units are rated lower: for example 160 m for several DIN-rail dimmers and 100 m for the RFTC thermostats (see each unit's page). Inside a building every wall takes part of the signal.

| Material                            | Signal that gets through |
| ----------------------------------- | ------------------------ |
| Wooden structures with plasterboard | 80–95 %                  |
| Ordinary glass                      | 80–90 %                  |
| Brick walls                         | 60–90 %                  |
| Reinforced concrete                 | 20–60 %                  |
| Metal partitions                    | 0–10 %                   |

Three rules from the unit manuals:

* Do **not** install units in a metal box, or in a switchboard with metal doors.
* Keep at least **1 cm** between units.
* Radio control is not recommended for equipment that protects life or safety, because a signal can be shielded or a battery can run flat.

## 2. Test the link from the real place

{% stepper %}
{% step %}

#### Put the unit where it will be installed

Power it on the bench near the final position, or fit it. Do not install it in a closed metal box before you test.
{% endstep %}

{% step %}

#### Stand where the controller will be used

Press the button. The light (or the unit's LED) should react **every time**. Try ten presses, with 1 s between them. If you are not sure about "every time", the link is too weak.
{% endstep %}

{% step %}

#### Try the worst case

Test with doors closed, and from the farthest room. Note which button positions fail.
{% endstep %}
{% endstepper %}

{% hint style="info" %}
An installer can measure the link: the **RFAF/USB** service key with the *Wireless analyzer* software shows signal strength and quality between the place of the controller and the unit, and also possible interference. The software is on inels.com/partners.
{% endhint %}

## 3. Fix it, in this order

{% stepper %}
{% step %}

#### Move things

Move the unit away from metal, pipes and large metal surfaces. If you can, move the controller. A short distance can matter more than anything else.
{% endstep %}

{% step %}

#### Give a unit in a switchboard an antenna

Several units (for example RFSA-61M, RFSA-66M, RFUS-61, RFDEL-71M, RFDEL-76M, RFDA-73M/RGB, RFIM-40B) have an SMA socket. A short **AN-I** antenna is in the box. In a metal switchboard use an external antenna for better reception.

| Antenna         | What it is                                                     | Gain    |
| --------------- | -------------------------------------------------------------- | ------- |
| **AN-I**        | Internal antenna, 17 × 44 × 8.5 mm, packed with the unit       | 2.1 dBi |
| **AN-E**        | External antenna                                               | 5 dBi   |
| **AN-E3**       | External antenna, **IP67**                                     | 3 dBi   |
| Extension cable | 10 m for an external antenna. It does **not** change the range | —       |

Measured range from a controller to an RFSA-66M, with direct sight:

| Antenna | RFGB  | RFWB  | RF KEY |
| ------- | ----- | ----- | ------ |
| AN-I    | 305 m | 290 m | 190 m  |
| AN-E    | 300 m | 290 m | 200 m  |
| AN-E3   | 275 m | 260 m | 180 m  |

With direct sight the antennas give a similar range. An external antenna matters when the unit would otherwise sit inside metal.
{% endstep %}

{% step %}

#### Switch on the repeater function of a unit in between

A unit marked **RFIO2** can pass on messages for other units. This lets the signal reach farther over existing units (in the order of 50 m). You switch it on with the **RFAF/USB** service key and a PC, or in the app.

```mermaid
flowchart LR
    C["Controller"] -->|"weak"| U1["RFIO2 unit<br/>repeater function ON"]
    U1 -->|"strong"| U2["Unit out of reach"]
    C -.->|"too far"| U2
```

Not every unit can do this. For example the RFMD-100 motion detector has **no** repeater function.
{% endstep %}

{% step %}

#### Add an RFRP-20N repeater

The **RFRP-20N** plugs into a mains socket and keeps the through-socket usable.

* It increases the range between a controller and a unit by up to **200 m**.
* It is designed for up to **20 components**.
* **Green LED** = it has power. **Red LED** = it is active (receiving or sending).
* It comes in three plug versions: Schuko, British, French.

Plug it in **between** the controller and the unit, where it can still hear both.
{% endstep %}
{% endstepper %}

{% hint style="info" %}
To set which components an RFRP-20N repeats, follow the instruction manual supplied with the RFRP-20N.
{% endhint %}

## 4. Test again

Repeat section 2. If all ten presses work from the farthest place, you are done.

## If it did not work

| What you see                                  | Cause                            | Fix                                                                                     |
| --------------------------------------------- | -------------------------------- | --------------------------------------------------------------------------------------- |
| Works next to the unit, not from the room     | Walls or metal in between        | Move the unit or controller. Then try the repeater function or an RFRP-20N              |
| Works only sometimes                          | Weak signal at the edge of range | Add a repeater half way. Keep 1 cm between units                                        |
| Unit is in a metal switchboard                | Metal blocks radio               | Use an external antenna AN-E or AN-E3 on the SMA socket. Do not mount it in a metal box |
| Detector is far away                          | Detectors have a limited range   | Add a repeater. The RFMD-100 itself cannot repeat                                       |
| Everything worked, then stopped               | Flat battery in the controller   | Replace the battery. Then test again                                                    |
| Pairing works but the button is slow or wrong | Presses too fast                 | See [Tutorial 7](/inels-home/inels-wireless/tutorial-7-fixing-mistakes.md)              |

***

## What you learned

* Range is up to 200 m in open space and much less through concrete and metal.
* Test from the real place before you finish the installation.
* Fix order: move, antenna, repeater function, RFRP-20N.
* A unit with the **RFIO2** mark can repeat for other units.

## Try this before moving on

1. Measure which of your rooms fails. Draw the walls between the controller and the unit.
2. Move a unit 1 m and test again.
3. If you have an RFRP-20N: watch the red LED while you press a button.

**Next:** [Tutorial 9 — adding a gateway](/inels-home/inels-wireless/tutorial-9-adding-a-gateway.md)