1. Introducció
The Velleman VM144 is a telephone ring detector designed to provide a visual and electrical indication when a telephone line receives an incoming call. It features a powerful LED that flashes upon detection of a ring signal and a relay output for connecting external devices. This manual provides essential information for the proper installation, operation, and maintenance of your VM144 unit.
2. Informació de seguretat
- Font d'alimentació: Only use a 12VDC/100mA adapter (e.g., PS1203) as specified. Using an incorrect power supply can damage the device and void the warranty.
- Connexions elèctriques: Ensure all connections are made correctly and securely. Incorrect wiring can lead to malfunction or electrical hazards.
- Només per a ús interior: This device is intended for indoor use in dry environments. Do not expose it to moisture, rain, or extreme temperatures.
- Manipulació: Manipuleu la unitat amb cura. Eviteu deixar-la caure ni sotmetre-la a impactes forts.
- Manteniment: No intenteu obrir ni reparar la unitat vosaltres mateixos. Encarregueu tot el manteniment a personal qualificat.
3. Producte acabatview i Característiques
The Velleman VM144 is a compact and efficient device for monitoring telephone line activity. Its primary function is to detect an incoming ring signal on a standard PSTN (Public Switched Telephone Network) line and provide both a visual alert and a relay activation.

Image: Velleman VM144 unit (left) and its circuit board (right).
This image displays two components: on the left, the Velleman VM144 unit enclosed in its gray and red casing, featuring a small red indicator light. On the right, the internal circuit board of the VM144 is shown, revealing various electronic components including a blue relay, a red capacitor, and an RJ11 connector.
Característiques principals:
- PSTN Line Connection: Easily connects in parallel with any standard telephone line using an RJ11 connector.
- Indicació visual: Features a powerful 10,000 mcd LED that flashes brightly when the phone rings.
- Sortida de relé: Includes a Normally Open (NO) contact relay output, capable of handling up to 1A, for triggering external devices.
- Flexible Relay Operation: The relay output can be configured for continuous activation or to pulse in rhythm with the telephone ringing.
- Disseny compacte: Supplied with a protective enclosure for durability and ease of installation.
- Aplicacions versàtils: Ideal for noisy environments, for the hearing impaired as an additional ringer, or to integrate with other systems.
4. Configuració i instal·lació
Follow these steps to properly set up your Velleman VM144 unit:
- Connexió d'alimentació: Connect a 12VDC/100mA power adapter (not included, e.g., Velleman PS1203) to the designated power input jack on the VM144 unit.
- Connexió a la línia telefònica: Locate an available RJ11 telephone jack or a telephone line splitter. Connect the VM144 unit to the PSTN line using an RJ11 cable. The unit is designed to connect in parallel with your existing telephone equipment.
- Relay Output Connection (Optional): If you intend to use the relay output to control an external device, connect the device's control wires to the Normally Open (NO) contacts of the VM144's relay. Ensure the external device's power requirements do not exceed the relay's maximum rating of 1A.
- Col·locació: Place the VM144 unit in a suitable location where the flashing LED is visible, or where its relay output can effectively trigger the connected external device.
Nota: The unit will only feature a relay output if connected to a 12VDC power supply. Without external power, only the passive telephone line detection and LED flash functionality may be available, depending on the specific model variant.
5. Instruccions de funcionament
Once properly installed, the Velleman VM144 operates automatically:
- Ring Detection: When an incoming call is received on the connected telephone line, the VM144 detects the ring signal.
- Alerta visual: The powerful LED on the unit will begin to flash, providing a clear visual indication of the incoming call.
- Relay Activation: If a 12VDC power supply is connected, the internal relay will activate. The relay output can be configured to either remain continuously closed during the ringing period or to open and close in rhythm with the telephone's ringing pattern. This allows for flexible control of connected external devices.
- Call Termination: When the telephone call is answered or stops ringing, the LED will cease flashing, and the relay will return to its normally open state.
6. Manteniment
The Velleman VM144 is designed for low maintenance. To ensure optimal performance and longevity:
- Neteja: Periodically wipe the unit with a soft, dry cloth to remove dust. Do not use liquid cleaners or abrasive materials.
- Medi ambient: Keep the unit in a clean, dry environment, away from direct sunlight, excessive heat, and moisture.
- Inspecció: Occasionally check the power and telephone line connections to ensure they are secure.
No user-serviceable parts are inside. Do not attempt to open the enclosure.
7. Solució De Problemes
If you encounter issues with your VM144, refer to the following troubleshooting guide:
| Problema | Causa possible | Solució |
|---|---|---|
| LED does not flash when phone rings. |
|
|
| El relé no s'activa. |
|
|
| Funcionament intermitent. |
|
|
8. Especificacions
| Especificació | Detall |
|---|---|
| Número de model | VM144 |
| Font d'alimentació | 12VDC / 100mA (adapter not included) |
| Indicador LED | 10,000 mcd |
| Connexió de la línia telefònica | RJ11 connector, connects to PSTN line |
| Relay Output Contact | Normalment obert (NO) |
| Relay Output Current Rating | 1A màx |
| Dimensions | 80 x 55 x 35mm (3.15 x 2.16 x 1.37 polzades) |
| Mode d'operació | Automàtic |
| Data de primera disponibilitat | 10 de novembre de 2011 |
9. Garantia i Suport
Velleman products are designed and manufactured to high-quality standards. For specific warranty information, please refer to the documentation provided with your purchase or visit the official Velleman website. For technical support or inquiries, please contact your local Velleman distributor or reseller.





