Setup UVMFR-7 Frequently Asked Questions

FAQ Legend:

All Products Product Class (Rotating Shadowband Radiometers) This Product (UVMFR-7)

2. Setup

1. We have verified the direction of geographical North-South and the motor axis is parallel with earth's polar axis. For many months the shadowband shadeed correctly. But now the shadowband tip does not shadow the diffuser entirely. Each day the gap of shadow becomes larger (headed toward the summer solstice) or smaller (headed toward the winter solstice).

This tends to happen near summer solstice and is an adjustment issue:

1. Using a protractor, cut a small (roughly 3") triangle of thin cardboard with the angle of your site latitude. Now slip the triangle under the motor case between the stand and the motor housing, to verify your motor's shaft angle is equal to your site latitude. This must be set to within about a degree, and once set, you can forget about it.

2. Check that your motor assembly is pressed all the way back against the machined slide (a both points top and bottom), If there is a small gap loosen the screw and press the motor hard against the slide and re-tighten the clamp.

3. Assuming the above two items are set correctly, the band may have been bent slightly out of round. Gently bend it down (not too much) and try that.

For further help, see our support system:

http://www.yesinc.com/support/supportwizard.html

2. The shadowband is not shading the diffuser at all times of the day (early, solar noon or late in the day). What's wrong?

This is clearly a system setup/alignment issue. Even if a shadowband correctly shades later at a different time of year, it was not", something is not aligned. Check:

-YESDAS time is set precisely within a few seconds of GMT?

-Aligned geographical north/south (and verified at solar noon?)

-Level the diffuser (not via the bubble level at the base, check the black diffuser ring itself with a machinist's level)?

-Verify motor angle with a paper template (and verify the motor is pushed into the slide fully and bolts are snug)?

-Verify band stops at nadir location (use your thumb/forefinger)?

-Was band bent in shipment (use a paper template)?

Please see http://www.yesinc.com/support/supportwizard.html

for more help