AutoOpen DIG – automatic door opening module for digital intercom systems

In customer service areas, time and workflow efficiency matter. When there’s no need to talk through the intercom, walking to the handset just to press “open” wastes valuable time. AutoOpen DIG is a compact smart module that, after detecting a valid ring signal, automatically lifts the handset, unlocks the door, and hangs up – quickly, reliably, and without interfering with the main control unit.

The device works with popular digital intercom systems (including MIWI-URMET, Laskomex, Proel, ACO, and Elfon). Listening time and reaction parameters can be adjusted to match your building’s installation and workflow.

1. Who is it for and when does it make sense?

AutoOpen DIG is ideal wherever conversation is unnecessary and quick, repeatable door opening is needed:

• reception desks, offices, front desks,
• medical, cosmetic, or therapy rooms,
• customer service points, repair centers, and public offices,
• storage rooms, workshops, or entrances with high foot traffic.

From real-world use: each door opening saves 5–30 seconds. In office receptions, deployments have delivered 15–40 minutes of time savings per day.

2. How it works – operating logic

The module analyzes the intercom ring signal on the L+/L- line (or from a microphone). After detecting a valid call for a given apartment or office:

1. It simulates lifting the handset (HOOK),
2. Activates the door release relay (DOOR) for a set duration,
3. Hangs up and returns to standby mode.

A built-in safety cooldown (e.g. 15 seconds) prevents repeated activations within the same ring cycle.

3. Compatibility – digital intercom systems

• MIWI-URMET (e.g. LM-8, LM-9, 1132, 1133, 620),
• Laskomex (e.g. CD-2502, CD-3100, CD-4000),
• Proel, ACO, Elfon – and other digital intercoms using L+/L- signal lines.

AutoOpen DIG requires no changes to the central unit – it works in parallel with the existing handset.

4. Installation – “two wires + USB”

• Connect L+ and L- in parallel with the intercom handset,
• Power the module via USB 5 V (USB power adapter, PC port, or USB plug),
• Optionally, use a microphone input for complete acoustic isolation – useful in complex or noisy systems.

Configuration is done via USB serial connection – no need to open or dismount the device.

Loss of USB power does not affect normal intercom operation – when the module is unplugged, the system continues to work exactly as before.

5. Configuration and operating modes

Main parameters can be configured from a PC through a serial terminal:

• Listening time 1–5 s – how long a valid ring must be detected,
• Continuous signal duration (e.g. 2 s) – required length of valid detection,
• Door open time (e.g. 5 s) and lift/hang-up times,
• Cooldown (e.g. 15 s) – ignore repeated triggers,
• Schedule mode – enable only during selected days/hours,
• Door count logs – daily, weekly, monthly, and total.

The DIG mode (digital) uses threshold-based detection of ring pulses; a tone-analysis mode is also available for specific signal patterns.

6. Business benefits

• Time savings – 5–30 seconds per door event, 15–40 minutes daily in busy offices,
• Always available – the door opens even when staff are occupied,
• No changes to the central unit – quick and risk-free setup,
• Consistency and control – adjustable schedule, counters, and timing.

7. Technical specifications

8. Safety and integration

• Signal isolation via optional microphone input,
• No interference with the central unit – connects only to the handset side,
• Does not affect the audio or power circuits – removing the module does not impact intercom operation,
• Expandable for data logging, system integration, or extra I/O.

9. FAQ – common questions

Will it work with my system?
If your building uses a digital intercom with an L+/L- line (e.g. MIWI-URMET, Laskomex, Proel, ACO, Elfon), it’s usually compatible.

Can it operate only during business hours?
Yes – the schedule mode allows selecting specific days and times.

Do I need to reprogram the central unit?
No – AutoOpen DIG works independently, on the handset side only.

Does it count door openings?
Yes – optional counters show daily, weekly, monthly, and total activations.

10. Summary and contact

AutoOpen DIG automates door opening after a valid ring – no conversation, no walking to the handset, no interference with the building’s intercom control unit. Installation takes only two wires (L+/L-) and a USB power cable, and configuration is quick and straightforward.

Want to learn more or request a ready-to-use module?
Contact us: sklep@hesta.pl

AutoOpen DIG automatically detects the intercom ring and opens the door in MIWI-URMET, Laskomex and other systems – saving time in offices, receptions and clinics.