NESA BF Leaf wetness and rain presence sensor



Product Introduction
Product Features
Technical Details
Product Introduction

The leaf wetness sensor allows to determine the degree of wetting on the foliage, the duration of a certain state (wet or dry) and determine whether there are precipitations (rain). In function of the degree of wetting, the sensor detects a change of the electrical resistance on the elements of the grid and the output signal can be acquired by a data logger.

  • High precision leaf wetness sensor
  • Easy to install and with low weight
  • According to WMO standards
  • Easy to clean up and maintain

Product Features

  • Leaf wetness or water (rain) presence
  • Conforms to standard WMO
  • Sturdy and compact design
  • Easy to install and low weight
  • Electrical Output: 0÷2VDC (variation on multiple levels-max 15÷0Vdc=dry; wet=2.0Vdc) or 4÷20mA or RS485/Modbus; presence rain on/off dry contact.
  • Operating conditions: -30 ÷ +60°C
  • Power supply: 10÷30Vdc

Technical Details

Area 28cm2
Operating range (Dry / Wet)
Time constant 2 sec (medium time)
Working temperature -30 ÷ 60°C
Response time < 2 sec
Standard signal output 0÷2 Vdc (0Vdc = asciutto; 2.0Vdc = bagnato); o 4÷20mA o RS485/Modbus;

0÷2Vdc (0Vdc=dry ; 2Vdc= wet), 4÷20mA or RS485/Modbus

Protections Polarity reverse and transient
Made of Glass reinforced to protect the gold foil
Power  consumption 10÷30 Vdc ; 25µA@12Vdc (typical);
Weight 340g
Dimensions detector surface 50×70 mm (LxH) (max 54×70 mm)


Standard cable

Shielded multi-core cable for indoor/outdoor use, suitable for hot and cold climates.

With IP68 waterproof connector for connecting the sensor, and PS2 plug connector for direct connection to the data logger or with terminal sleeves for insertion into the terminal blocks.

Our cables are standard for most our sensors.

Available in different lengths starting from 1m.

Special Cable

NPI shielded cable. With IP68 waterproof connector for connecting to the sensor, and terminal sleeves for insertion into the terminal blocks.

Available in any length.

Bracket / Arm Support

Fixing system for Nesa’s sensors, composed by an arm of different lengths (50cm, 90cm, 150cm) and thermoplastic resin clam for external, able to withstand to extreme temperature and to solar radiation.

Two stainless steel screws for the tightening of the clamp on the sensor complete the equipment.

MCS Signal Conditioning Module

Single channel module for conditioning digital and analog electrical signals. Fully programmable for binding input/output with the USB interface available as an option.

·       Programmable input signals: Pt100, thermopiles, Voltages up to 2Vdc, Current 0÷20mA or 4÷20mA, frequency up to 1000Hz, Counter for pulses (1ms min)

·       Programmable Output signals: voltage 0÷2Vdc; Current 0÷20mA or 4÷20mA Serial RS485 (command line); Modbus RS485

·       Resolution: 18 bits with over 262,000 points

·       Operating conditions: -40 ÷ +80°C

·       DIN rail mounting

·       Power supply: 10÷30Vdc (typ. 4mA@12 Vdc)