Campbell Scientific CS700 Tipping Bucket Rain Gage and CS700H Heated Rain Gage - Manual (Page 30)

Appendix A. CS700H Operation
When the CS700H is “not Active” the status LED flashes every 1.5 seconds.
When the ambient temperature sensor detects the temperature falling below the
“Active On temperature” (+4°C) then the system becomes “Active” and the
snow sensor is enabled (see Figure A-2). The status LED flashes slightly
faster at 2 flashes per second–indicating the system is active.
When the proximity sensor detects snow (for 5 seconds continuously), the
heater elements are turned on and the block temperature sensor is monitored.
The heaters are controlled so that the temperature inside the funnel reaches the
Set Point temperature (+10°C).
The actual block temperature will be higher than the set point as
substantial heat is dissipated. NOTE
The lower heating block keeps the tipping bucket and the drain tubes from
freezing up. While the heater elements are turned on, the status LED flashes
even faster at eight flashes per second.
FIGURE A-2. Diagram Depicting Overall Operation
A-2