Positioning a sensor - Amazon Monitron

Positioning a sensor

To detect abnormalities in machine components, mount sensors in all locations where temperature and vibrations can be measured effectively.

To achieve the greatest accuracy:

  • Mount the sensor directly onto the housing of the target component

  • Minimize the length of the vibration transmission path, the distance between the source of vibration and sensor

  • Avoid mounting the sensor in a location that can oscillate due to natural frequencies, such as sheet metal covers

Vibration will attenuate up to 30-36" (75–90 cm) from the source.

Attributes of the vibration transmission path that can reduce the transmission path length include:

  • The number of mounting surfaces, which can cause signal reflection

  • Materials such as rubber or plastic, which can absorb vibration


Amazon Monitron sensors are 3-axis vibration sensors. The X, Y, and Z marks indicate the directions of the 3 three axes. Therefore, it is not necessary to align any particular axis with the direction of the asset's vibration.

The following example of an electric motor pump set shows sensor locations, with four positions, two on the motor and two on the pump.

The following example shows where you might mount sensors if your primary concern is the motor rather than the pump.

Gearboxes and bearings are also examples of common locations where you might want to place sensors.

For complex equipment with multiple moving parts (such as gearboxes), position the sensor to minimize the length of the transmission path from the primary vibration source. Note that vibration is reduced when it is transmitted between adjacent parts of equipment, so the shortest distance between the sensor and the source of vibration is not always the best option.

The following example of a gearbox shows how vibration can be transmitted through equipment in this way, along with a potential location for a sensor to detect this vibration.

For other types of equipment, the best position can be less obvious. For example, when placing a sensor to monitor bearings, position it close to the bearing's load zone, which is based on the direction of the load on the bearings as shown below.

Different types of loads on the bearings result in different load zones. Placing the sensor as close as possible to the center of the load zone is most likely to provide the best data.

For information about how to mount sensors, see Mounting a sensor.