The Texas Electronics, Inc. TR-525USW Rainfall Sensor is a remote tipping bucket style rain gauge that measures the amount of liquid precipitation. The Rain Gauge is a freestanding receptacle for measuring precipitation.
It contains an open top, which allows rainfall to fall into the upper portion, which is called the collector. Collected water is funneled to a mechanical device (tipping bucket), which incrementally measures the rainfall accumulation and causes a momentary closure of a switch. As water is collected, the tipping bucket fills to the point where it tips over. This action empties the bucket in preparation for additional measurement. Water discharged by the tipping bucket passes out of the rain gauge with no need for emptying.
The TR-525USW was specifically designed to meet the National Weather Service’s requirements for rainfall measurement.
This unit is a TR-525USW equipped with a rain gauge heater, the HT-525, for use where snow or freezing weather may occur. The rain gauge heater assessory consists of two low-power heating elements that prevent snow or sleet from accumulating in the collector and disrupting rainfall readings. The heater are thermostatically controlled with an additional thermal overload. The heater are ideally balanced to keep the gauge clear at all times yet minimize the amount of evaporation.