Surface Humidity Indicator LB-910
- functions: conductometer
- measurement: surface humidity, leaf humidity
- two cable connection
- measurement transmission to long distances
DESCRIPTION
Indicator LB-910 is used for signaling the presence of precipitation
or dew out dropping. It is a stationary device, of small size, powered
from an outside power supply. It is characterized by a modern
construction based on efficient and energy saving microprocessor
controller.
The device takes cyclic measurements of the measured surface
resistance, which is made in a form of a golden comb. The surface
resistance decline indicates precipitation (or the appearance of dew).
In order to designate the actual surface resistance value a
microprocessor built-in in the device uses digital calibration data
stored during the calibration process in the device's nonvolatile
memory. The result is sent from the device in a digital form (digital
current loop) to a supervisory system of data collection (i.e. using a
transitory LB-371 through an interface RS-232C to a computer,
meteorological station panel LB-741 or to a
converter LB-486). The interface parameters
allow on sending data along with powering the device using a two cable
line of any polarity.
TECHNICAL DATA
| RESISTANCE MEASUREMENT |
| Scope of measurement |
0...65000 ohm |
| Accuracy |
10 % (measured value) +/- 20 ohm |
| WORK CONDITIONS |
| Temperature |
-30...+70 °C |
| Humidity |
0...100 % |
| POWER SUPPLY |
| Scope of voltage |
8..24 V DC |
|
| Energy consumption |
4 mA |
average |
| 25 mA |
maximum |
Output interface
- current loop S300 LAB-EL, 300 bit/s, 7
data bits, 1 stop bit, without evenness control
Overall dimension
- 80 x 60 x 185 mm (width x height x length)
