Campbell Scientific CS700 Tipping Bucket Rain Gage and CS700H Heated Rain Gage - Manual (Page 7)

CS700 and CS700H Rain Gage
2.1 Heated Rain Gage
Snow Sensor and Heater
Operating Temperature Range: -20° to +5°C
Output: SDI-12
Voltage Requirements
Main
Power: 10 to 30 Vdc or 12 to 28 Vac
SDI-12 Power: 9.6 to 16 Vdc
Total Current Consumption (See Figure 2-1)
Snow sensor off, heater off: 6 mA @ 12 V, 0.072 W
Snow sensor on, heater off: 12 mA @ 12 V, 0.144 W
Snow sensor on, heater on: 5.8 A @ 12 V, 70 W
As the ambient temperature falls below the “Active On Temperature” (default
4°C), the heater will turn on to heat the funnel area of the rain gauge. Once the
funnel reaches the “Funnel Set Point Temp” (default 10°C), the heater will
begin cycling on and off with a duty cycle dependent on the ambient
temperature, keeping the funnel temperature at or near 10°C.
FIGURE 2-1. Heater Operation
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