Double verification tilt and lux detection manhole cover open sensor

It adopts one piece capacitive accelerometer sensor to detect the tilt change of the manhole cover and an additional luminance sensor to detect the lux change inside the manhole to correctly judge the closed/open status of the manhole cover, the built-in NB-IoT communication module will update the data packet to cloud sever immediately if stats change is confirmed, the cloud sever will send real time SMS/Email/Siren alert notification to the relative personnel for further inspection.

wireless bluetooth vibration sensor

The detector is installed on the downside of the manhole cover. It measures the current inclination angle of the manhole cover and the current lux value as background. The manhole cover is detected as “Be Open” when both the inclination angle of manhole cover is over 15° (threshold value configurable) and the manhole brightness changes is over 10% in short time; the sensor sends this information to the cloud server by NB-IoT cellular network immediately, and the cloud platform will send real time SMS/Email/Siren alert notification to the relative person.


  • Capacitive MEMS (digital) accelerometer & luminance sensor
  • Double verification, false ratio < 0.1%
  • Detect the open or closed status of the manhole cover
  • Wireless communication: NB-IoT network
  • Remote monitoring
  • SMS/Email/Siren alert notification
  • Powered by long-life battery (2~3 years)
  • Transparent tempered plastic case
  • IP68 waterproof, not damaged if the manhole overflows


  • Manhole cover opening detection
  • Manhole illegal access
  • Manhole cover broken
  • Land subsidence

Extension Function

  • Water overflow detection
  • Gas pressure detection
  • Hazardous gas detection
Parking Lot Sensor
Sensor 3-axial MEMS sensor
and auxiliary photosensitive sensor
Resolution 8mg / 0.028Lux
Wireless Connectivity
Network NB-IoT:LTE Cat NB2
Transmitting Power: 23dBm±2dB
Receiving Sensitivity: -114dBm(no retransmit)
          -130dBm(with retransmit)
SIM Card Type Micro SIM Card
Power source Built-in lithium battery 8000mAh@3.6V
Battery life 3 years
Battery Changeable Yes
Case Material Transparent High Intensity Plastic
Dimensions Ø 90 mm * height 33 mm
Weight 120 g
Installation Surface Mounting
Operating temp -20 ℃ to +55 ℃
Ingress Degree IP68
Compressive strength >20,000 kg

Each sensor needs installing a NB-IOT network SIM card to communicate with the cloud server, the cloud sever works as a gateway to receive data from each sensor, the monitoring website or mobile APP could be constructed on this cloud server.

The data upload from the sensor to cloud server is mostly 30~60 bytes each time, data upload time is different for different sensors too, by this elements, thousands of sensors could work together independently and monitored from one interface.

Topology WiiEMS