Albedo

Albedo measurements are a supported feature of the SunSentry system (sensors and accessories sold separately). This measurement is made using two pyranometers, typically a pair of class A or class C sensors. One pyranometer faces upward and the other faces downward. The CM275 Albedometer Mounting Stand (an accessory for the CM410 mount) co-locates both sensors on a single bracket that is mounted to the CM410 arm or another horizontal crossarm, such as the CM206.

Mount the albedo sensor away from obstructions that could block or otherwise interfere with incoming sunlight. Similar to the CM400 (SunSentry met station mount), the CM410 (Pile Mount Arm for Albedo) is designed to mount a remote albedometer to a separate driven pile (e.g., W6x12). Refer to Driven piles for information about orientation and recommended site placement.

The following table and figures show the suggested pile and mounting plate heights. The top of the pile should be at least 1.09 m (43 in) and less than 1.58 m (62.5 in) above flat ground. 1.75 meter albedo height shows the ideal mid-range of 1.34 to 1.42 m (53 to 56 in).

Albedo mounting height

Albedo height m (ft)

Pile height m (ft)

Plate height m (ft)

1.50 (4.92)

1.09 (3.58)

0.67 (2.21)

1.75 (5.74)

1.42 (4.67)

0.92 (3.03)

2.0 (6.56)

1.58 (5.21)

1.17 (3.85)

1.5 meter albedo height

1.75 meter albedo height

2 meter albedo height

Mounting procedure:

  1. Mount plate to pile using hook bolts. Ensure vertical edges of plate are plumb. Bottom of plate should be 28 to 44 inches above the ground for the installed albedo height to be within the industry recommended height of 1.5 to 2 meters (59 to 78.7 inches) above the ground. Tighten nuts to 15 to 20 ft-lb initially.

  2. Loosely install struts using serrated bolts. The bolts should be threaded only partway to allow strut rotation.

  3. Attach the arm to the plate flanges using a long bolt and nuts. Loosely tighten the nuts, ensuring the arm can rotate freely.

  4. Connect the arm to the struts using a second long bolt and nuts. Loosely tighten the nuts to allow arm adjustment. The distal end of the albedo pipe should be approximately horizontal.

  5. Tighten all bolts and nuts, ensuring proper alignment is maintained.

  6. Mount the sensors on the CM275 bracket. Refer to the sensor manuals for more information.

  7. Slide the albedo sensor onto the end of the arm and secure it to the arm using the provided mounting hardware.

  8. Route the cables down the arm to the enclosure.

  9. Connect the cable wires to the terminal buses inside the enclosure (see RS-485 BUS).

  10. Secure the cables to the arm using cable ties.