Frequently asked questions

• Can it be installed without a neutral wire in the back box?

  Yes — that is exactly what "neutral optional" means. The ZS-SR-EU1 wires correctly both without a neutral and with one. Without a neutral it runs in no-neutral mode and draws its holding current through the load, so a sensible minimum load is needed — check with very low-power LEDs. With a neutral it switches any load up to 10A, with no limits.
• How does it differ from the -LN- version (ZS-SR-EU1-LN)?

  They are the same Star Ring family but differ in wiring. This model, "neutral optional", works without a neutral too — the pick for older buildings where the box has only line. The -LN- version mandatorily needs line plus neutral and suits renovations where the neutral already reaches the switch. Electrically both carry 10A.
• Which Zigbee gateway do I need?

  A Zigbee/Tuya gateway (a MOES/Tuya hub), not included in the box. Without it the switch toggles the key locally but does not join scenes, schedules or remote control. With the gateway in the home it appears in the Tuya / Smart Life app and binds into automations. At CasaSmart we will help you pick the right gateway.
• Can I control it by voice with Alexa, Google Home or SmartThings?

  Yes, through the gateway. Linked in the Tuya / Smart Life app, the switch answers voice commands via Alexa and Google Home, and as a Tuya Zigbee device it also works in compatible SmartThings hubs. Apple Home is not natively supported. Every path goes through the gateway, never straight from the switch.
• What is the Star Ring and what is it for?

  The Star Ring is an illuminated circular ring on the glass panel that glows softly like a starry sky. Beyond looks, it is a practical indicator: it shows from across the room whether the line is on and marks the button's position in the dark — handy in a hallway or bedroom. On this model the panel is grey.
• Will the light still work if the internet goes down?

  Yes. Pressing the key switches the line directly, regardless of the network. Zigbee commands travel locally between the switch and the gateway, so scenes and automations keep working offline. The internet is only needed for remote access and cloud voice assistants.
• What colours and formats does the series have?

  This SKU is grey, single-gang (1 gang). The same "neutral optional" Star Ring series also comes in white (ZS-SR-EU1-WH-MS), and for more circuits there are 2-gang and 3-gang options. For lines where the neutral already reaches the switch there is the -LN- series with a mandatory neutral.