Fruit Dendrometers.


Fruit Dendrometer

  • The Implexx Fruit Dendrometer is ideal for irrigation and scientific research;
  • Measure small to large fruits for growth, sizing and harvest management;
  • SDI-12 digital output for data loggers, LoRaWAN and internet enabled devices;
  • 0.001 mm resolution for precision measurements;
  • Easy to install and very low ongoing maintenance.


A series of absolute displacement sensors provides recording both size and growth rate of intact rounded fruits in three diameter ranges within 7 to 160 mm.

Two phenomena affect fruit diameter. These are growth and internal water content. The growth component is usually dominant. At the same time, in some cases, the fruit may loose water that is manifested in deceleration of growth rate or even shrinkage of the fruit. It may be a result of water stress, lack of light, or another limiting factor.

Thus, the FI-type sensor allows investigating effect of irrigation rate and other environmental factors on both water balance and growth of fruits. Another exiting application of the sensor is monitoring of harvested fruits during storage.

The FI-type sensor consists of an LVDT transducer mounted in a special clip and a DC powered signal conditioner.

The probe is connected by a standard 1-meter cable to the waterproof box with the signal conditioner inside.

The output cable length should be specified in the order if required.

Original parallelogram design of moving arms provides firm and straight positioning of the sensor's flaps on a fruit under study.

FI-LT (large), FI-MT (medium) and FI-ST (small) models have different clips for providing three measurement ranges: 30 to 160, 15 to 90 and 7 to 45 mm, respectively.


Ideal for Internet Enabled Devices and Remote Field Monitoring

The fruit dendrometers are ideal for IoT devices and remote field monitoring because:

  • It operates via the SDI-12 protocol which is supported by a wide range of data loggers and telemetry units;
  • It has low power requirements and can be supported off small batteries;
  • It is quick to install (less than a few minutes) and ongoing maintenance is minimal.

The team at Implexx can provide data loggers and telemetry devices. Our international network of accredited dealers and agents also have a range of data acquisition options that may be unique to your specific location. Otherwise, we can assist in connecting our dendrometers to your existing irrigation monitoring or data acquisition system.


Irrigation Monitoring, Carbon Allocation, Growth Rates, and More

The fruit dendrometers are suitable for a wide range of applications including:

  • Fruit sizing and harvest management;
  • Irrigation monitoring and scheduling;
  • Fertigation or nutrient monitoring and scheduling;
  • Carbon allocation, biomass accumulation and relative growth rates;
  • Maximum Daily Shrinkage (MDS) and other calculated variables.



Feature Specification
Fruit Size FI-LT: 30 to 160 mm | FI-MT: 15 to 90 mm | FI-ST: 7 to 45 mm
Measurement Resolution FI-LT: 0.065 mm | FI-MT: 0.038 mm | FI-SMT: 0.019 mm
Noise < 1 mV w/filter, 1 kHz cutoff
Output SD-12
Supply Voltage 5 to 24 VDC
Excitation Time 5 seconds
Returns Value After 0.3 seconds
Operating Temperature 0 to 50 ℃
Cable length between sensor and signal conditioner 1 m
Cable length between signal conditioner and data logger 5 m (standard) | 60 m (maximum)
Warranty 1 year

Manual & Docs


The FI-MT dendrometer installed on a mango:

The dendrometer field monitoring system


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