English: View of Zomeworks passive tracker pivot. Image by User:Leonard G.

This is is a 1998 model designed specifically for ASE DG-285 and DG-300 panels (the single glass panels to the left are unitized pairs of Kyocera 167G panels that are temporary replacements for some damaged ASE panels). Zomeworks now produces "universal" racks in various sizes that are capable of mounting a wide variety of solar panels as shown on the Zomeworks website.

This rack is in the morning position against the stops. The light blue framework mounting the panels moves to follow the sun in response to heated fluid/gas, the heating controlled by shaders (not seen here). The upper part of of the medium blue mechanism carries the "polar" pivot and is adjusted in pitch (pivoting around the large blue bolt) twice a year at the equinoxes for Spring/Summer and Fall/Winter seasons. Here the rack is seen in the Spring/Summer position suitable for the 38 degree north latitude of the location. Two threaded receiver positions for the position bolt at a different angular spacing than the mount bolt holes allow a total of four positions. Use of the first and third positions are sufficient for this application with the second and fourth suitable for locations nearer to the equator. Equatorial locations would require a different fixed head configuration while extremely high latitudes would be better served with a powered vertical axis or two axis altitude-azimuth tracker.

The dark blue cylindrical objects are viscous hydraulic dampers, similar to automotive shock absorbers.

Nighttime tie-down

A simple self releasing tie-down mechanism is used to ensure a quick early morning wakeup, which would otherwise take up to an hour, since fluid would have to be forced from the low side to the high side, requiring considerable differential heating. A plastic-coated wire clothesline tie–down connects an eye on the moving tracker rack to a bronze ring. At nighttime pullover the ring is hooked under a cleat. The weight of the ring is sufficient to ensure release but light enough so as not to require rebalancing of the system. A light spring tensioner pulls out nine to ten inches of slack, preventing release due to tracker motion in response to nighttime winds. The pull-over brings the tracker just past level, since if brought down too far the system will not release if the most of the morning sky is foggy or overcast, and only a slight tip toward dawn will greatly assist the fluid flow. The tie down system will release after ten to fifteen minutes of sun exposure if tied down the night before, longer if pulled over in the morning. Additional production in this 2340 WDC two-tracker system is estimated at 1KWH per day, enough for an extra 60 miles per month in the battery electric vehicle used at this location.