4 optional cnf4 heater/ventilator, 1 cnf4 specifications, Optional cnf4 heater/ventilator – Campbell Scientific CNR4 Net Radiometer User Manual
Page 20: Cnf4 specifications
CNR4 Net Radiometer
Field of view
Upper:
Lower:
180 degrees
150 degrees
Net-irradiance:
–250 to +250 W/m
2
Non-stability:
< 1% (sensitivity change per year)
Window heating offset:
< 6 W/m
2
(1000 W/m
2
solar
irradiance)
Uncertainty in daily total:
< 10% (95% confidence level) indoor
calibration
Typical signal output for
atmospheric application:
±5 mV
Temperature sensors
Thermistor:
10k Ω
Pt-100:
DIN class A
Instrument calibration:
Indoors, side by side against reference
CG(R) 3 pyrgeometer. On request
outdoors, side by side against
reference CG(R) 4 pyrgeometer
6.4 Optional CNF4 Heater/Ventilator
The purpose of the heater/ventilator is to prevent dew deposition on the
pyrgeometer and pyrgeometer window, thus enhancing the measurement
accuracy and reliability. Using the heater/ventilator will have negligible effect
on the pyranometer reading.
Generally, the errors caused by the heater/ventilator will be small relative to the
errors that would have been caused by water deposition.
6.4.1 CNF4 Specifications
Heater
Power consumption:
10 W @ 12 Vdc (15 Ω)
Ventilator
Power consumption:
Supply voltage:
5 W @ 12 Vdc
8 to 13.5 Vdc
Weight without cable:
0.5 kg (1.11 lb)
Operating temperature:
–40 to +80°C
12