Cross calls are one of the most common support issues in Tegui/BTicino video door phone installations: the neighbor in 2º B presses their panel and the bell rings in 3º A. Or worse: it rings on several floors at the same time. The system works, but it calls the wrong apartment.
This problem has a solution, and in most cases does not require changing the wiring. But it does require understanding why it happens. In this technical guide, we review the four main causes and how to address each one.
Incorrect or duplicated configurators
In the Tegui/BTicino 2-wire BUS system, each monitor or indoor phone must have a unique address assigned via configurators (also called jumpers or dip-switches depending on the model). If two units have the same configured address, both will respond to the same call: cross call guaranteed.
The most frequent situations that cause this problem:
- New installation with factory configurators: all monitors leave the factory with the same default address. If they are not reconfigured before installation, all floors will receive all calls.
- Replacing a monitor without reconfiguring: a faulty monitor is replaced and the new one is installed without adjusting its address. If it matches another floor, there is a cross.
- Installation expansion: a second monitor is added on a floor (for example, in the kitchen) and it is forgotten to assign a different subaddress from the main monitor.
Solution: verify that each indoor unit has a unique address. For 2-wire installations, the Tegui Coding Kit Green Configurators 2-Wire System (BTicino 306065) (€13.04) includes the configurators needed to correctly reassign addresses. For more complex installations, the BTicino 3501K Configuration Kit (€78.10) allows more advanced programming.
System resets and configuration loss
Some Tegui/BTicino monitors and phones store their address in volatile or semi-permanent memory. This means certain events can cause a loss or corruption of the configuration, making the device revert to its factory address.
Events that can cause a reset or address loss:
- Prolonged power outage: especially in older models without EEPROM memory.
- Micro-cuts on the BUS: fluctuations on the 2-wire line can cause partial resets in some monitors.
- Failed firmware update: on touch screen monitors (Classe 100/300), an interrupted update can leave the device in factory state.
- Accidental reset button press: some models have a reset button on the back that is easy to activate unintentionally during handling.
Solution: after any power outage or system handling, verify that all monitors maintain their correct address. If resets are frequent, check the power supply stability: a BTicino 346030 Compact 2H 2 DIN Power Supply (€98.44) or a BTicino 346040 2-Wire Audio Power Supply (€81.32) in poor condition can cause micro-cuts that destabilize the entire installation.
Incorrect configuration of primary and secondary panels
In buildings with more than one outdoor panel (for example, one at the main entrance and another at the garage or a secondary entrance), the Tegui/BTicino 2-wire system requires that one panel be configured as primary (master) and the others as secondary (slave).
If two panels are configured as primary simultaneously, the BUS system conflicts and can cause erratic behavior, including cross calls or calls that do not reach any floor.
This error is especially common in these scenarios:
- Replacing an outdoor panel without checking the master/slave configuration of the new one.
- Installing a second panel by copying the configuration of the first without changing the role parameter.
- Factory reset of a secondary panel, which reconfigures it as primary by default.
Solution: access the configuration of each outdoor panel and verify that only one is in primary mode. In the Linea 3000 Black 2-wire Audio/Video RFID Panel (BTicino 343093) (€316.85) and other models in the range, this parameter is adjusted via dip-switch or from the installer menu. Check the installation manual of your specific model to locate the correct parameter.
Addressing errors in complex installations
In installations with multiple floors, splitters, and more than 8-10 indoor units, addressing becomes more delicate. The Tegui/BTicino 2-wire system uses a two-level address structure: floor address and monitor subaddress within the same floor.
The most common addressing errors in complex installations:
- Overlapping address ranges: in installations with floor splitters, if the address ranges assigned to each branch overlap, monitors on different floors can interfere with each other.
- Misconfigured splitters: the Tegui 2-Wire System Floor Splitter (BTicino 346841) (€40.57) must be properly configured to isolate each branch. A faulty or poorly adjusted splitter can propagate signals between floors that should be isolated.
- Mixing product generations: combining monitors from different generations (for example, first-generation Classe 100 with Classe 100X) can cause incompatibilities in the addressing protocol.
- Outdated documentation: in buildings with several interventions over the years, the original addressing plan may not reflect the current reality of the installation.
Solution: create or update the installation’s addressing map before intervening. Assign non-overlapping address ranges to each branch and document them. In large installations, it is advisable to perform a general reset and reassign all addresses from scratch following a planned scheme.
Quick diagnosis: where to start?
If you face an installation with cross calls and don’t know where to start, follow this checklist:
- Check the addresses of all indoor monitors. Make sure no two units have the same address. This is the most frequent cause and the easiest to fix.
- Review the configuration of the outdoor panels. Confirm that only one is in primary mode if there is more than one panel.
- Check the power supply condition. A degraded power supply can cause micro-cuts that generate resets and configuration loss.
- Inspect the floor splitters if the installation has more than one floor or branch.
- Document the current addressing map before making any changes.
In most cases, the problem is solved in steps 1 or 2 without needing to touch the wiring.
Need help with your installation?
If after reviewing these points the problem persists, or if you prefer direct guidance, contact us indicating the model of the outdoor panel and the indoor monitor model. With that information, we can give you a specific answer.
And if you need to replace any component, these are the most common in this type of intervention: