The DEX20, DEX70, DEX100 and DEX200 are highly precise electronic dendrometers that measure the growth and size of plant stems and fruits. The effects of environmental factors on the water balance of plants and stem size variations over time are easily monitored with a temperature compensated dendrometer. The DEX is a caliper-style device with a full bridge strain gage attached to a flexible arm. The output signal is then recorded by a data logger or computer in real time. The millivolt sensor output shows both the diurnal and long term growth of the plant. The device has been used to test plants under conditions of water stress, elevated ozone and other atmospheric pollutants. Applications for screening plants for growth rate and stress tolerance are also common.

Features

  • Non-destructive
  • Real-time measurements
  • Adaptable to computer systems
  • Long-term measurements possible
  • Weatherproof and rugged for field study
  • Caliper body - milled alloy
  • Stainless steel flex band
  • Four balanced, temperature compensated strain gages
  • Electronics sealed and weatherproofed
  • (5) clamping blocks provided, 3 for stems and 2 for fruits
  • Wires directly to datalogger
Units DEX20 DEX70 DEX100 DEX200
Measurement Range 5 - 25 10 - 70 25 - 100 95 - 200
Expansion Range 0 - 5 0 - 13 0 - 13 0 - 13

Demensions

Length

Width

Height

 

65

19

38

 

102

25.4

51

 

155

25.4

76

 

263

38

153

Weight 55 g 180 g 230 g 572 g

Standard Clamping Blocks

Dimensions Set 1

Face Radius

Dimensions Set 2

Face Radius

 

19 x 19 x 6

5mm

19 x 19 x 6

25 mm

 

25 x 25 x 9.5

70 mm

25 x 25 x 13

5 mm / 50

 

25 x 25 x 9.5

108 mm

25 x 25 x 13

25 mm / 75

 

25 x 25 x 905

200 mm

 

Optional Clamping Blocks

Dimensions

Spherical Radius

 

19 x 19 x 6

25 mm

 

25 x 25 x 9.5

70 mm

 

25 x 25 x 13

105 mm

 

38 x 38 x 7

500 mm

Units DEX20 DEX70 DEX100 DEX200
Operating Range -10 to 50ºC -10 to 50º C -10 to 50º C -10 to 50º C
Temperature
Stability
0.0025 mm / º C 0.0025 mm / º C 0.0025 mm / º C 0.0025 mm / º C
Accuracy Over
20º C Range
0.050 mm 0.050 mm 0.050 mm 0.050 mm
Units DEX20 DEX70 DEX100 DEX200
Signal Output Range ±5 mV ±5 mV ±2.5 mV ±2.5 mV
Output Sensitivity .5 mV/mm .22 mV/mm .13 mV/mm .05 mV/mm
Conversion Mult 2.0 mm/mV 4.5 mm/mV 7.7 mm/mV 20 mm/mV
Output LInearity ±01 mV/mm ±006 mV/mm ±004 mV/mm ±004 mV/mm
Electrical Noise Limit ±0.01 mV ±0.01 mV ±0.01 mV ±0.01 mV