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Smart Lock Power and Wi-Fi Requirement Checker

Review the planned power approach and connectivity requirement before purchase.

Inputs

Power and network

Straight-line distance; walls counted separately.

Result

Drain index (1 low, 2 mid, 3 high)
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Locks supported per hub/AP
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Over capacity (1 = yes)
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PoE run length (m, 0 = battery)
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Estimated 2.4 GHz RSSI (dBm)
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Smart-Lock Power, Signal, and Battery Life

Signal decides the protocol

Estimate 2.4 GHz RSSI from router distance plus 9 dB per wall. Above -65 dBm suits direct Wi-Fi; -65 to -75 is marginal; below -75, use a hub or move the access point. More than 6 Wi-Fi locks per access point needs a dedicated SSID.

Battery math

Wi-Fi drains fastest, Z-Wave/Thread slowest. Freezing weather cuts alkaline capacity first; lithium holds up. Treat the low end of the interval as the shopping trigger and keep one spare set per lock.

Verify before you buy

  • Record 2.4 GHz RSSI twice at the door
  • Count walls and locks on the band
  • Test egress and outage behavior