Wired RS-485 Wall Switch Integration
for Modern Smart Homes.
Phantom Controls turns the mechanical state of a conventional latching dry-contact wall switch into an addressed digital event, carries that event over a shared low-voltage RS-485 bus and bridges it to a local IP smart home control system.
From Dry-Contact Wall Switch
to Smart Home Automation.
Latching wall switch
A conventional dry-contact mechanism supplies a stable open/closed state.
Phantom-TX
Reads the state, applies its field-set address and transmits an event.
4-wire RS-485
24V, GND, A and B form the shared field trunk.
Phantom-RX
Receives bus events and bridges them to the automation network.
A Latching Switch Interface
Designed to Disappear.
The transmitter has one deliberately narrow job: read a latching contact, apply a field-set address and report the state change over the shared bus.
Switch input
Phantom Bus
Phantom-TX is designed for latching switch inputs, not momentary-only keypad architecture.
Smart Home Integration
at the Rack.
The receiver is the bridge between the deterministic RS-485 field bus and the software-driven automation network.
Low-Voltage Wall Switch Automation
Built as Infrastructure.
The current wired smart home switch architecture is a shared four-conductor field trunk. TX nodes tap the same 24V, GND, RS-485 A and RS-485 B conductors, while the receiver serves as the bus endpoint and integration gateway.
| Design consideration | Current direction |
|---|---|
| Switch type | Latching dry-contact wall switches |
| Bus | 4 conductors: +24V, GND, RS-485 A, RS-485 B |
| Topology | Daisy-chain / trunk with addressed TX taps |
| Device identification | Two-digit field-set rotary addressing |
| Shared addressing | Permitted when multiple physical switches should trigger the same function |
| TX termination | Not located at each transmitter |
| Receiver termination | 120 Ω at bus endpoint |
| Network side | Local Ethernet / IP gateway |
Engineering specifications shown here describe the current beta architecture and may change before production certification. Final cable limits, certification requirements and installation rules will be established through validation testing.
Lutron HomeWorks/QSX and Control4
Wall Switch Integration Targets.
The hardware at the switch can stay consistent while integration logic evolves at the receiver. Current targets include Lutron HomeWorks QS/QSX and Control4, alongside additional professional control ecosystems.
Integration support is under active development and validation. Platform names are trademarks of their respective owners.
Want to evaluate the hardware?
We are looking for qualified integrators, technical partners and design-driven projects for structured beta evaluation.