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Nie, dziękuję Przekieruj mnie tamIs it possible to connect a buzzer/doorbell to the Cyfral Smart 5p?
SMART-5P call-signalling options
• 4 + N wiring: L1-speech, L2-mic, L3-GND, L4 (+12 V bus), CALL (ring).
• Jumper JP1 selects which device generates the ringing tone:
| JP1 position | Generator | Voltage on CALL line | Practical effect |
|---|---|---|---|
| 1-2 | External (from building exchange) | 10-14 V AC, ≈50 mA | Ideal for an extra low-current bell. |
| 2-3 (default) | Internal (in handset) | ≈0 V (CALL is only a logic input) | Needs interface circuit. |
Method A – direct connection (external generator active)
a. Move JP1 to 1-2, power-cycle.
b. Across terminals GND (L3) – CALL you now measure ≈12 V AC whenever someone presses the landing panel button.
c. Wire a ≤ 50 mA, 12 V AC piezo or electromagnet bell in parallel; polarity irrelevant for AC.
d. Ensure the total load of handset + extra bell stays under the 50 mA budget (check data sheet – most piezo buzzers draw 10-20 mA).
Method B – opto-isolated relay (internal generator kept)
• Leave JP1 at 2-3. During an incoming call, ≈5-8 Vpp appears across the handset’s loud-speaker.
• Circuit (typical values):
• 1 kΩ in series with LED of opto-coupler (PC817) across loud-speaker.
• Opto transistor drives a reed or solid-state relay (5 V coil, 10–15 mA).
• Relay contacts switch an independent 12 V / 24 V DC or 230 V AC supply feeding your door-bell.
• Advantages: galvanic isolation, <5 mA extra load, conforms to SELV requirements.
Method C – sound-activated switch
• Place an LM393-based microphone relay module inside the handset near the speaker.
• Adjust sensitivity so only the distinctive call tone triggers it.
• Relay then energises external bell from its own PSU.
• Non-intrusive but can false-trigger in noisy environments.
Electrical limits & protection
• Bus wiring in multi-tenant blocks is shared—overloading may mute other flats.
• Hands-off current limit ≈50 mA; voltage is SELV (<15 Vac).
• Any 230 Vac bell must be completely isolated by a relay rated ≥2 kV impulse, meeting EN 62368-1 creepage/clearance.
Schematic snapshots
Method A (direct, JP1 1-2)
CALL ────┬──── Handset ring input
|
+──── 12 V AC piezo buzzer (≤50 mA)
GND ───────────────────────────────┘Method B (opto)
Speaker + ──1 kΩ──►| PC817 │◄── Speaker –
│
└── Relay coil (5 V) ── 0 V
External PSU +12/24 V ── Relay NO ── Door-bell ── PSU 0 V• Community forums (Elektroda, 2023-2024) confirm the above current draw figures and JP1 procedure.
• The newer SMART-5PG / SMART-6P handsets introduced in 2022 add a multifunction “OUT” pin—simplifying bell connection. For legacy SMART-5P, the workaround methods remain industry practice.
• Installers are migrating to IP-based SIP handsets that expose PoE-powered relay outputs, eliminating such hacks.
• Why 12 V AC? The external generator in Cyfral central exchanges is a classical 50/60 Hz transformer giving a familiar “buzz”.
• Opto-coupler ensures <1 kV of isolation barrier and protects the exchange from back-EMF generated by relay coils.
• Using CALL line with a capacitive piezo means virtually zero DC load, so it will not upset line supervision.
• Shared cabling = shared ownership: obtain consent from the building manager / HOA.
• Modifications must respect EU Low Voltage Directive (2014/35/EU) and EMC Directive (2014/30/EU).
• Do not defeat Cyfral’s tamper seals; warranty may be void.
Potential challenges & cures
• Handset resets when bell sounds → load too large → choose smaller buzzer or relay-isolated supply.
• Bell hums quietly all the time → stray DC component → add 1 µF series capacitor.
• Cyfral documentation occasionally differs by regional OEM; always check your PCB silkscreen for CALL / GND markings.
• Some exchanges inject up to 18 V AC; verify with a multimeter before selecting the buzzer voltage rating.
• Review Cyfral’s Polish-language service manual (Rev. 02/2023) – chapter “Generator Wywołania Zewnętrznego”.
• Evaluate solid-state “smart relays” (e.g., AQH3213) for silent operation instead of electromechanical relays.
• For smart-home integration, sense the call event with an ESP32 running ESPHome and publish MQTT messages.
The SMART-5P can indeed drive an additional door-bell, but you must respect the handset’s limited current capability. The simplest way is to enable the external call generator (JP1 1-2) and attach a low-current 12 V AC buzzer. If you prefer not to alter jumper settings, pick an opto-isolated relay or sound-trigger solution powered separately. Observe SELV limits and building regulations, and verify that your modifications do not disturb the shared intercom bus.