DD-L Diameter Dendrometer Large
The DD-L series dendrometers are used for high-precision and continuous measurement of stem diameter changes. These devices are suitable for long-term application in outdoor conditions. Due to their extremely low power consumption, Ecomatik dendrometers are ideal for battery-powered solutions, e.g., in IoT applications.
DD-L dendrometers are specially designed for small- to medium-sized stems and branches (with diameters ranging from 3 to 30 cm; DD-L1W, max. 20 cm diameter). DD-L dendrometers are fixed to the measuring object with two UV-resistant elastic bands. This simple and very stable mounting method fixes the sensor at the desired measuring point without exerting excessive pressure on the trunk surface. DD-L dendrometers are available in four versions:
- DD-L1: with a measuring range of 11 mm for species with slow and average growth rates.
- DD-L2: larger measuring range of 25 mm for fast-growing species.
- DD-L3: larger measuring range of 50 mm for very fast-growing species.DD-L1W (previously DDW): hermetically sealed to withstand extreme environmental conditions, e.g. high humidity, underwater, below snow cover, near the ground surface, elevated exposure to dust or corrosive agents (e.g. coastal sands, volcanic ash), etc. The DD-L1W is (suitable for trunk diameters between 3 and 20 cm)
Advantages
- Suitable for small to medium stems and branches with diameters between 3 and 30 cm (DD-L1W, 3 – 20 cm)
- Lightweight sensor
- Injury-free installation, minimal pressure on the plant
- Maximum stability against wind, snow, falling branches and fruit
- Diameter-specific frame size available for diameters ranging from 3 – 30 cm
Specific to the DD-L2 & DD-L3 models
- Extended measuring range; reduced maintenance effort (i.e. longer time interval between readjustment of the dendrometer frame) for fast-growing species
Specific to the DD-L1W model
- Hermetically sealed to withstand extreme environmental conditions: e.g. high humidity, underwater, below snow cover, near the ground surface, elevated exposure to dust or corrosive agents (e.g. coastal sands and salt, volcanic ash), etc.
Limits of the DD-L series
- Not suitable for diameters > 30 cm (or > 20 cm DD-L1W), (see types DC and DR for diameters > 30 cm)
Specific to the DD-L1, DD-L2 & DD-L3 models
- Not suitable for operation under extreme environmental conditions: e.g. high humidity, underwater, below snow cover, near the ground surface, elevated exposure to dust or corrosive agents (e.g. coastal sands, volcanic ash), etc. (see model DD-L1W)
Models
| Models | Suitable fordiameter | Measurement range |
|---|---|---|
| DD-L1 | 3 - 30 cm | 11 mm |
| DD-L2 | 3 - 30 cm | 25 mm |
| DD-L3 | 3 - 20 cm | 50 mm |
| DD-L1W (hermetically sealed) | 3 - 20 cm | 11 mm |
Technical data
Sensor model name | Diameter Dendrometer large Types DD-L1 and DD-L1W (hermetically sealed) | Diameter Dendrometer large Type DD-L2 | Diameter Dendrometer large Type DD-L3 |
Scope of application | Slow/average growth rates | Fast-growing | Very fast growing |
Suitable for diameter | DD-L1: 3 – 30 cm; DD-L1W: 3 – 20cm | 3 – 30 cm | 3 – 30 cm |
Special features/limitations | DD-L1W: sealed to withstand a wide range of operational conditions, see below. | Extended measurement range, for fast-growing species | Extended measurement range, for very fast-growing species |
Measurement range | 11 mm linear | 25.4 mm linear | 50.8 mm linear |
Resolution | Data logger dependent e.g.: CR300 series: 0.01 µm Dendrometer logger DL18: 0.2 µm | Data logger dependent e.g.: CR300 series: 0.03 µm Dendrometer logger DL18: 0.5 µm | Data logger dependent e.g.: CR300 series: 0.05 µm Dendrometer logger DL18: 1 µm |
Accuracy | Dendrometer dependent: max. ± 4.5% of the measured value (stable offset) Data logger dependent e.g.: CR300 series: ± (0.04% of the measured value + 0.3 µm) Dendrometer logger DL18: ± (0.1% of the measured value + 0.45 µm) | Dendrometer dependent: max. ± 1.97% of the measured value (stable offset) Data logger dependent e.g.: CR300 series: ± (0.04% of the measured value + 0.6 µm) Dendrometer logger DL18: ± (0.1% of the measured value + 1 µm) | Dendrometer dependent: max. ± 0.98% of the measured value (stable offset) Data logger dependent e.g.: CR300 series: ± (0.04% of the measured value + 1.2 µm) Dendrometer logger DL18: ± (0.1% of the measured value + 2 µm) |
Output signal | Analogue, 0V to Vex (excitation supply voltage) | Analogue, 0V to Vex (excitation supply voltage) | Analogue, 0V to Vex (excitation supply voltage) |
Temperature drift of the sensor | < 0.2 µm/°C in the whole measurement range | < 0.2 µm/°C in the whole measurement range | < 0.2 µm/°C in the whole measurement range |
Linearity | < 1% | < 0.7% | < 0.5% |
Operational conditions | All Models: normal outdoor field conditions, -25 to 70 °C, 0 to 100% relative air humidity; Hermetically Sealed Model DD-L1W: even under extreme environmental conditions (underwater, below snow cover, under exposure to strongly corrosive substances e.g. saltwater, ash, aggressive agricultural chemicals) | All Models: normal outdoor field conditions, -25 to 70 °C, 0 to 100% relative air humidity | All Models: normal outdoor field conditions, -25 to 70 °C, 0 to 100% relative air humidity |
Weight (sensor without cable) | 13 g | 33 g | 43 g |
Power supply | Vex (! stabilized !) 0.5 to 10 VDC, Power consumption max. 0.28 µWh per measurement | Vex (! stabilized !) 0.5 to 10 VDC, Power consumption max. 0.28 µWh per measurement | Vex (! stabilized !) 0.5 to 10 VDC, Power consumption max. 0.28 µWh per measurement |
Material | Stainless steel and aluminium | Stainless steel and aluminium | Stainless steel and aluminium |
Sensor cable length | 5 m, extendable on request to max. 100 m | 5 m, extendable on request to max. 100 m | 5 m, extendable on request to max. 100 m |