Why does a no-neutral smart switch need a capacitor?

Explanation

In a no-neutral installation, the smart switch needs a small current to stay powered. Some lighting loads, especially low-watt LED lights, may react to this current by flickering, glowing faintly or causing the switch to become unstable. The capacitor provides a more stable path for the small current at the light side. If the manufacturer includes or recommends a capacitor, it should be installed for reliable operation.

Common mistakes

• Skipping the capacitor
• installing it at the wrong light circuit
• using a random capacitor value.

Troubleshooting / next steps

• If flickering or offline issues happen after installation, check capacitor position and load compatibility first.

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