FAQ
TL;DR: A 40-circuit star-wired switchboard, 14 roller shutters and ~120 IP/Wi-Fi devices can be automated with Home-Assistant plus Shelly/SONOFF for <€1 000 hardware, but “manual control must be” retained for reliability [Elektroda, Daro1003, post #20868007]
Why it matters: early wiring decisions lock in future smart-home options.
Quick Facts
• Shelly 2.5 PM roller-shutter module: ~150 PLN, two channels, native % positioning [Elektroda, Daro1003, post #20865963]
• SONOFF Dual R3 after firmware flash: ~50 PLN per two relays [Elektroda, Daro1003, post #20865963]
• User run: 70+ ZigBee/Wi-Fi nodes on one router without dropouts [Elektroda, freebsd, post #20869453]
• Reported failure: 3 / 14 Shelly 2.5 (21 %) died, 8 fixed by capacitor swap [Elektroda, Daro1003, post #20990333]
• Replacing 26 contactors with 13 Shelly units saves ≈0.8 m DIN-rail space [Elektroda, Berend, post #20865691]
Should I skip wall switches and rely only on the app?
No. In-room buttons give instant, fail-safe control when phones or Wi-Fi fail. "Manual control must be" kept [Elektroda, Daro1003, post #20865963] A low-voltage push-button wired to a digital input costs <10 PLN and adds redundancy.
PLC or Home Assistant—what’s better for a house build?
Home Assistant (HA) on Raspberry Pi or mini-PC offers hundreds of ready integrations, auto-updates and community support. Users moved from Carel PLC to HA after hardware dropouts [Elektroda, Berend, post #20993048] PLCs shine in industrial IO density but need coding time and costly modules.
How does Shelly 2.5 achieve percentage roller-shutter positioning?
During calibration Shelly measures full up/down time and then drives the motor for a matching fraction of that time. Position errors self-correct after each full travel [Elektroda, Daro1003, post #20865963] No extra sensors are required.
Are Shelly and SONOFF reliable long-term?
Expect some failures. One user lost 3 of 14 Shelly 2.5 in three years (21 %); another eight units needed capacitor replacement due to overheating [Elektroda, Daro1003, post #20990333] Keep modules ventilated or choose DIN-rail Pro versions with improved power supplies.
Will 100+ Wi-Fi smart devices overload my network?
Modern routers handle ≈250 clients; a forum member runs 70+ devices with no issues after upgrading to an ASUS AP [Elektroda, freebsd, post #20869453] Use separate 2.4 GHz SSID for IoT and wired backhaul to reduce airtime contention [Cisco, 2021].
How do I integrate Satel Integra alarm with HA?
Add the ETHM-1 Plus Ethernet module and enable TCP. HA’s ‘satel_integra’ integration pulls zone states and lets detectors trigger automations [Elektroda, Daro1003, post #20865963] Keep Satel as a certified security layer and let HA handle convenience logic.
Can Home Assistant drive wired thermoelectric actuators?
Yes. Pair a multi-relay board (e.g., SDM-16RO) via Modbus RTU; expose relays as climate entities. Use DS18B20/ESP32 room sensors and HA’s PID “generic_thermostat” to modulate loops [Home Assistant Docs].
What size switchboard do I need for 40 circuits and smart modules?
A 1 × 0.8 m cabinet fits ~14 DIN rows. Roller-shutter relays alone occupy 13 × 18 mm = 234 mm; leave 30 % spare for future PV, UPS or EV breakers [Elektroda, Berend, post #20987063]
How do I prevent blackout darkness?
Put a 12 V LED strip on Satel’s battery output. When 230 V fails, HA sees power-loss, and the panel lights the hallway for a preset time [Elektroda, freebsd, post #20870588]
Are dimmers worth installing?
Most users skip dimming; they rarely adjust brightness after novelty wears off and dimmers cost 2-3 × a relay [Elektroda, Daro1003, post #20987893] Use tunable-white smart bulbs if mood lighting is essential.
How do I add a Shelly 2.5 to Home Assistant?
- Wire live/neutral and motor leads per diagram.
- Power up, connect to Shelly’s Wi-Fi AP, set your LAN SSID.
- In HA, Settings → Devices → Add Integration → Shelly. Device appears with two relays and position slider [Shelly Docs].
What edge cases should I plan for?
Modules may enter configuration mode after mains resets, causing blinds to move unexpectedly [Elektroda, Daro1003, post #20990333] Install a physical key switch that kills shutter supply during vacations.
Which cable to run to window switches?
Route 3×1 mm² for motor power plus UTP or 8×0.5 mm² for future sensors; both terminate in the switchboard [Elektroda, Daro1003, post #20988360]