Lima Shield documentation: user guide and technical specifications

LIMA SHIELD is an anti-intrusion sound shield designed by a French company: Lima Groupe, an integrated security group founded in 2022, whose teams have backgrounds in the army, the police and private security.

An alarm detects and alerts. The Lima Shield acts while the intrusion is under way: as soon as it is confirmed, it can first warn the intruder with a sequence of beeps, then it floods the space with a sound designed to make them flee. Active protection, without contact and without direct confrontation.

Technology of military origin, regulated for civilian use

The sound can be set from 86 to 138 dB and is emitted in sequence, alternating with pauses. A 10-second delay gives you time to disarm before any sound is emitted.

A secure app

Lima Shield's communications are encrypted and have undergone a cybersecurity audit by the Lima Cyber teams, so that no third party can take control of the device remotely.

An award-winning innovation

LIMA SHIELD received the Audience Award at the Nuit de la Sécurité Globale 2025, organised by Républik Group. Nearly €1 million has been invested in research and development, and the product is designed to last 10 years.

Read our story

The Lima Shield's sound output can be set from 86 to 138 dB. It is emitted in sequence, alternating with pauses, for the duration you choose in the app.

Power

86 to 138 dB, adjustable

Frequency

2 to 5 kHz band, where the human ear is most sensitive

Modulation

Several times per second, to prevent habituation

Coverage

70 to 100 m² per unit, depending on the configuration and the acoustics of the space

Warning

Optional sequence of beeps before any sound is emitted

Delay

10 seconds, giving you time to disarm

Emission

In sequence: the sound alternates with pauses

Duration

Adjustable in the app, “Alarm” tab

The Lima Shield measures 29 × 26 × 16 cm and weighs about 7 kg. It can stand on a piece of furniture or a shelf, or be wall-mounted on its bracket.

Dimensions

29 × 26 × 16 cm

Weight

About 7 kg

Protection

IP54: resistant to dust and moisture

Installation

Free-standing (furniture, shelf) or wall-mounted on its bracket

Height

Preferably at mid-height or high up, facing the area to be protected

Use

Indoor and semi-outdoor areas

The parts of the Lima Shield, front and back, and the accessories that go with it.

Front

Protective grille

It protects the sound system

Motion detector

Passive infrared sensor (PIR)

Thermal sensor

Reads 192 heat points. It is not a camera: no images are captured

Status LED

Shows the status of the Lima Shield (see “Status LED”)

Support arm

The Lima Shield sits on its stand or mounts on the wall

Back

Power button

Starts the Lima Shield and is used to reset it

Power input

24 V mains, cable included

Ethernet port

RJ45, for a wired connection to your router

Integration port

Connection to an alarm control panel and existing detectors

Detection

Detectors

Motion, thermal and tamper

Small frames

The sensors recognise small frames and low-level movement, such as a cat's

Accessories

Control

Mobile app, remote and panic button

Access

Code keypad and badge

The Lima Shield connects to the Internet over Wi-Fi or Ethernet, with 4G backup, and is controlled from the Lima Shield Connect app.

Internet

Wi-Fi 2.4 GHz or Ethernet (RJ45 port)

Backup

Built-in 4G, which takes over in the event of an outage

Pairing

Bluetooth, from the app

Home automation

Zigbee

App

Lima Shield Connect, on iPhone (App Store) and Android (Google Play)

Security

Encrypted communications, audited for cybersecurity

Power supply

24 V mains, cable included

Battery

Up to 1 month on the internal battery, and up to 3 months with the optional secondary batteries

Without power or Internet

The Lima Shield carries on protecting

The Lima Shield comes with a 2-year warranty and complies with European CE standards.

Warranty

2 years, excluding the battery

Compliance

European CE standards

Lifespan

Designed to last 10 years

Identification

A serial number for each unit, on the label at the bottom of the Lima Shield, above the connectors

Support

By phone on +33 6 73 28 14 96, or by email at support@limashield.com

The Lima Shield needs no installer: plug in one cable, then set everything up in the Lima Shield Connect app in 5 to 10 minutes. For screen-by-screen guidance, follow the step-by-step installation.

What you need

The Lima Shield

With its power cable, supplied

A power socket

Nearby

Your smartphone

With Bluetooth turned on

Your 2.4 GHz Wi-Fi

And its password, or an Ethernet cable connected to your router

The steps

1. Place the Lima Shield on a flat surface, near a socket. Plug the supplied cable into the back of the Lima Shield, then into the wall socket.

   

2. Press and hold the button on the back of the Lima Shield for at least 3 seconds. Its LED lights up white.

   

3. Install the Lima Shield Connect app and create your account (see how to download the app).

4. In the app, tap “Set up a Lima Shield”. Turn on your phone's Bluetooth if the app asks. No need to do anything on the Lima Shield itself: just stay within 5 metres, in the same room.

   

5. Tap your Lima Shield in the list (its name starts with LIMASHIELD), then tap “Pair”.

   

   

6. Choose how it connects to the Internet: “Wi-Fi” (recommended) or “Ethernet”, using a network cable between the back of the Lima Shield and your router. Either way, 4G takes over if there is an outage.

   

7. For Wi-Fi, choose your network, enter its password and tap “Join”. You can also scan your router's QR code.

   

   

8. When “Your Shield is ready” appears, give it a name if you wish, for example Home, then tap “Finish”. If an update is offered, tap “View update” to install it, or “Later”.

   

You are all set: the Lima Shield is connected and disarmed, and its status LED is solid white. To activate it, see how to arm the Lima Shield.

The Lima Shield can stand on a piece of furniture or a shelf, or be wall-mounted on its bracket. Ideally, place it at mid-height or high up, facing the area to be protected, near a socket.

Location

Indoors, or in a semi-outdoor area: it resists dust and moisture (IP54)

Height

Preferably at mid-height or high up

Orientation

Towards the area to be protected

Area

70 to 100 m² per unit, depending on the configuration and the acoustics of the space. Beyond that, add another Lima Shield

Power supply

Near a power socket, for the supplied cable

The Lima Shield Connect app is available on the App Store for iPhone and on Google Play for Android. All Lima Shield setup is done in the app.

1. On iPhone, open the App Store; on Android, open Google Play. Search for “Lima Shield Connect”, or use the buttons above.

2. Install the app, then open it.

3. Tap “Create an account”. Enter your email, your country and a password, then tap “Create my account”.

   

4. Allow notifications when your phone asks: that is how you are alerted in the event of an alarm.

To add your Lima Shield to the app afterwards, see how to install the Lima Shield.

The “Home” screen of the Lima Shield Connect app shows the status of your sound shield and lets you arm it, disarm it or trigger the SOS alert.

Lima Shield name

Its number and the name you gave it.

Alarm status

“Disarmed”, “Armed”, “Detection” or “Alarm”.

Arm or disarm

Tap “Arm” to start monitoring, “Disarm” to stop it.

SOS alert

Hold the SOS button for 2 seconds to trigger the siren immediately.

Internet connection

Wi-Fi or Ethernet, and the status of the 4G backup.

Battery level

The remaining battery charge.

Tabs

“Home”, “History” and “Settings”, at the bottom of the screen.

The Lima Shield goes through four states. The app screen and the status LED always show the current one.

Without a phone, you can also arm and disarm with the code keypad (see how to arm and disarm with the code keypad).

1. Disarmed

   Monitoring is off. Tap “Arm” to turn it on. The status LED is solid white.

2. Armed

   The screen turns green and shows “System armed”. The Lima Shield activates its detectors (motion, thermal, tamper) and monitors the protected site. The LED turns solid red.

   

   

3. Motion detected

   The screen turns orange. You have 10 seconds to tap “Disarm”.

   

4. Alarm

   Once that time is up, the siren goes off, the screen turns red and the LED flashes red. Tap “Stop siren” to silence it: the Lima Shield then stays armed.

   

To stop the Lima Shield's siren, tap “Stop siren” in the app: the Lima Shield then stays armed. You can also disarm it with the code keypad, a badge or the remote control, if they are installed.

If you do nothing, the siren sounds in sequence, alternating with pauses, for the duration set in “Settings”, then “Alarm” (see set and test the siren).

To stop monitoring, tap “Disarm” on the “Home” screen.

In an emergency, hold the SOS button on the “Home” screen for 2 seconds: the Lima Shield's siren goes off immediately. The panic button and the remote control, if installed, can also trigger it.

To stop it, see how to stop the siren.

It lists the Lima Shield's alarms, arming actions and events, from newest to oldest. The “All”, “Alarms”, “Arming” and “Device” filters narrow down the list. Each event shows who acted and how: from the app, the keypad or the remote control.

It brings together the settings for the Lima Shield and for your account. The Lima Shield settings are only available to the administrator account, the one used to install the Lima Shield.

Change

Shows another Lima Shield, or adds one with “Add a Shield”.

Alarm

Siren power and duration, siren test (see set and test the siren).

This device

Lima Shield name, network connection and updates.

Accessories

Remote controls, keypad and access codes (see add an accessory).

Turn off the Shield

Silences the siren and stops monitoring (see turn off or reset).

Reset the Shield

Restores the Lima Shield to its factory settings (see turn off or reset).

Account and people

Your account, the language and the people who have access to the alarm.

Log out

Logs your account out of this phone only.

You can give other people access to your Lima Shield. They will be able to arm it, disarm it and view the history, but not change its settings.

1. In “Settings”, tap “Account and people”, then “Invite someone”.

   

   

2. Enter the person's email and tap “Send invitation”.

   

3. The person appears as “Pending”. They create their account in the app with that email, then tap “Accept invitation”.

   

Cancel an invitation

Wrong address? Open the pending invitation in “Account and people”, then tap “Cancel invitation”.

To be guided screen by screen, follow the step-by-step guide to adding a contact.

In “Settings”, tap “Alarm”: this is where you set the siren's power and duration, and where you can test it. The Lima Shield's power is adjustable from 86 to 138 dB.

The Lima Shield can also be controlled without a phone: with a code keypad or a badge, a remote control or a panic button.

To add them, open “Settings”, then “Accessories”: this is where you manage remote controls, the keypad and access codes.

Add the remote control

1. In “Settings”, tap “Accessories”, then “Add an accessory”.

   

   

2. Tap “Lima Shield Remote”, the wireless SOS button.

   

3. Open the remote control: slide the small triangular tool provided into the notch on the side, then lever the two halves apart.

   

4. Activate the battery: pull out the plastic tab sticking out from under the battery.

   

5. Hold down the small circled button, to the right of the battery, for 6 seconds, until the red light flashes. Not the large round button on the other side. Then tap “Search”.

   

6. Keep the remote control close to the Lima Shield: the search takes one minute.

   

7. Give it a name if you wish, then tap “Finish”. It appears in your accessories.

   

   

Add the keypad

1. In “Settings”, tap “Accessories”, then “Add an accessory”.

   

   

2. Tap “Lima Shield Keypad”.

   

3. Install the batteries: open the compartment on the back of the keypad, insert the supplied batteries with the correct polarity (+/−), then close it.

   

4. Hold down the 0 key for 5 seconds, until you hear 3 beeps. You then have 30 seconds to tap “Search for keypad”.

   

5. The Lima Shield searches for the keypad nearby. When it finds it, the connection is made automatically.

   

6. Tap “Finish”. The keypad appears in your accessories, where you manage its codes under “Access codes”.

   

   

To be guided screen by screen, follow the step-by-step guide to adding the remote control or the keypad.

Once the keypad is added, see how to arm and disarm with the code keypad.

The code keypad arms and disarms the Lima Shield without a phone. It works with your personal six-digit code, set in “Settings”, then “Accessories” (see how to add a code keypad).

Arming and disarming work differently: disarming only requires the code.

To arm

1. Enter the six digits of your code.

2. Press the confirm key, at the bottom right of the keypad: it is marked with a bell and a hash sign.

   

To disarm

1. Enter the six digits of your code.

2. No need to press the star key afterwards.

When you arrive at a protected site, enter your code during the 10-second delay, before the siren goes off.

Check that the command went through

Look at the Lima Shield's status LED: solid red means it is armed; solid white means it is disarmed (see what the LED colour means).

If the Lima Shield cannot be seen from the keypad, the “Home” screen of the app shows its status, and the “History” tab also lists arming and disarming done from the keypad.

In “Settings”, tap “Change”, then “Add a Shield”. Then follow the same steps as for installation (see how to install the Lima Shield). Each Lima Shield protects 70 to 100 m², depending on the configuration and the acoustics of the space.

To switch from one Lima Shield to another in the app, tap “Change” in “Settings”.

Your Lima Shield units can be managed one by one, or work together in coordination: each one communicates with the others.

If you change your router or your Wi-Fi password, stay next to the Lima Shield.

1. In “Settings”, tap “This device”, then “Network connection”.

   

2. Choose “Wi-Fi” or “Ethernet” and follow the same steps as for installation (see the step-by-step installation).

   

3. If the change fails, the Lima Shield stays connected to its previous network.

The Lima Shield is updated remotely. If an update is offered, tap “View update” to install it, or “Later”. Updates can also be found in “Settings”, then “This device”.

Do not unplug the Lima Shield during the update.

Turn off the Lima Shield

In “Settings”, tap “Turn off the Shield”: this silences the siren and stops monitoring. First disarm the Lima Shield and stay next to it. To turn it back on, press and hold the button on the back of the Lima Shield for at least 3 seconds.

Reset the Lima Shield

In “Settings”, tap “Reset the Shield” to restore it to its factory settings, for example before passing it on to someone else. First disarm it and stay next to it, with an Internet connection.

The status LED, on the front of the Lima Shield, shows its state: disarmed, armed or alarm in progress.

The Lima Shield carries on protecting even without power or Internet: detection and triggering happen on the device itself.

Power outage

Its internal battery takes over: up to 1 month, and up to 3 months with the optional secondary batteries

Internet outage

The built-in 4G takes over to alert you

It is very unlikely. The Lima Shield's sensors are designed to recognise small frames and low-level movement: a cat or a young child has virtually no chance of triggering it.

Since no sensor is infallible, two safeguards come before any sound is emitted: the warning beeps, if you have turned them on, and the 10-second delay, which gives you time to disarm.

No. The Lima Shield has no camera and takes no images. Its thermal sensor reads 192 heat points, and its motion detector is a passive infrared sensor.

Its communications are encrypted and have undergone a cybersecurity audit, so that no third party can take control of the device remotely.

The Lima Shield is designed to make intruders flee, not to injure them. A very brief exposure causes at most temporary discomfort, without lasting effects. No substance is released, and there is nothing to clean up.

Before any sound

The warning beeps, if you have turned them on, then a 10-second delay to disarm

Duration

Adjustable in the app, “Alarm” tab; the sound alternates with pauses, in sequence

Power

Adjustable from 86 to 138 dB

Start with these checks. If they are not enough, our support team will help.

Contact support

Keep the serial number (SN) handy: it is shown on the label at the bottom of the Lima Shield, above the connectors.