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Sector antennas and PtP link mounted on their masts.

This past week, we’ve been evaluating our first cell site’s hardware in a lab environment. We’ve had it configured and running, connected to our existing network via PtP link. There are 3 sectors, 1 PtP, and a switch. Initially, 200 watts of monocrystalline solar power was planned to power the site. Increasing this to 400 watts in the future will enable the addition of a network camera and a power efficient computer. This is in place, but we’re still looking for suitable batteries. Ideally, we’d have 5,000 watt hours of battery capacity in a 24v bank. The mounting hardware for the masts will be strut channel mounted into wedge anchors that connect to the masts using pipe clamps. For the sectors, 2-5/8″ 16 gauge galvanized pipe is being used. For the PtP link, 1-5/8″ size. The solar charge controller, switch, power distribution, and PoE injection will all be done in a water-tight sprinkler controller box.

After 6 days of solar power, the site still appeared to operate properly; the lab battery bank however has shown to be insufficient for the load of the cell site, not able to support it for more than a day or two without clear sunlight. The panels themselves and the charge control seem to be working nicely, however. Note that in the graph, the voltages are approximately 1.0 V less than measured directly at the battery, due to wiring and fuse loss. The bank and solar setup in the lab are configured for 12v due to battery bank limitations, but 24v is the desired operating voltage for the permanent installation.

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The cell site hardware is coming along nicely, though the batteries have not yet been sourced.

As more progress is made, this blog post will be updated.