#40R anemometer

Off Grid Options presents an improved version of the popular three-cup design used in wind assessments for decades - our #40R Anemometer. It is manufactured to precise industry standards. The rotor is made of tough polycarbonate for exceptional durability and reliability. The sensor base is also made of rugged polycarbonate, making it more resistant to damage during installation than our competition. A green molded vinyl boot protects the anemometer wiring. Made in the USA with exceptional quality control. All units are tested mechanically and electronically before shipping.

Internally, the #40R anemometer has a fully hardened beryllium-copper shaft running in self-lubricating modified Teflon bearings. The rated bearing PV (pressure-velocity) factor is 20,000. At 6.7 m/s (15 MPH) the PV is approximately 500. At 44.7 m/s (100 MPH) the PV is approximately 2,000. Over-designed is an understatement.

Be sure to order our Anemometer Cable (part number APRSC1000) to connect your new anemometer to our Wind Data Logger.

Technical Specifications

Performance

• Accuracy: Within 0.1 m/s (0.2 MPH) for the range 5 m/s to 25 m/s (11 MPH to 55 MPH)
• Rotor moment of inertia: 92.2 x 10-6 kg-m2 (68 x 10-6S-ft2)
• Distance constant: 3 m (10 ft)
• Calibration: Not individually calibrated, calibration statistically based on samples

Output Signal

• Sensor type: Reed switch, dry contact, frequency proportional to cup rotational speed
• Transfer function: m/s = (Hz * 0.383) + 0.324; MPH = (Hz * 0.857) + 0.725
• Protection: Metal Oxide Varistor (MOV) between terminals

Physical Properties

• Cup diameter: 51 mm (2 in)
• Rotor diameter: 190 mm (7.5 in)
• Weight: 108 grams (3.8 oz)

Mounting and Wiring

• Mounts on: 12.7 mm (0.5 inches) round rod or tubing
• Mounts using: Set screw and cotter pin
• Wiring terminals: Two #4-40 brass screws with captive nuts