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The Safety Manhole system consists of an alert mechanism that rises up as the water level breaches the maximum level. The alert system warns pedestrians and motorists by flashing a high-beam LED light. The Municipality is also alerted by using LoRa wireless transmission.
To optimize maximum efficiency, electronics mounted on the drain cover work on low-power modes and transmit low-power wireless signals to a nearby Mater unit. The master unit is connected to a public utility system such as a street light and can act as an aggregator for multiple manhole alert systems nearby. The master unit sends an alert that a specific manhole water level has been breached due to flooding to the municipality. This is either done by using a LoRa-based wireless system or via 4G / 5G network.
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