The 255-100 Analog Output Evaporation Gauge is used to determine the evaporation rate by measuring the changing water level in an evaporation pan. A standard National Weather Service Class A Evaporation Pan is recommended. The sensor consists of a float, pulley, and counterweight attached to a precision 1000-ohm potentiometer mounted in a weatherproof housing. The triangular base plate is equipped with three leveling screws. The potentiometer produces a resistance output proportional to the position of the float which can be monitored on site using a data logger or remotely by telemetry equipment. The instrument can be placed directly in the pan, or connected to the pan using the 255-100P/F stainless steel pipe and fittings.
255-100 Evaporation Gauge Potentiometer: Accuracy: 0.25% Rotation: Continuous Resistance: 1000 ohms Operating temperatures: -40° to 60° C Linearity: 0.25% Range: 0-10" System accuracy: Evaporation gauge with pan and pipes ± 0.25% over 10" range Float: 4" diameter Height: 27-1/2" Diameter: 8" Base: 16" triangle with leveling screws Water input port: 1/2" NP coupling, female Cable: 3 conductor, 50' included Weight/Shipping: 7-1/2 lbs/15 lbs Shipping box: 29" x 17" x 16" 255-100-P/F Stainless Steel Pipe & Fittings Material: 304 stainless steel Dimensions: 60" long, 1/2" NPT fitting Weight/Shipping: 5 lbs/6 lbs