Eight total panels 12V DC each four parallel strings of two panels each
Ben Thornton in shorts and light shirt Jacob Torres barely visible behind panels in black t-shirt and cap
The blue Visitor Transport Saucer in the left foreground is actually a Pathfinder(TM) which is used to map the path of the sun relative to nearby sources of shade, to choose the optimal locations for solar panels, out of all shadows all day all year. Jacob is in the background taking a picture of panel wiring.
Another picture of our project array, with the Pathfinder(TM) in the foreground, from a different angle. Unfortunately, I did not take a close-up of the Pathfinder(TM) from directly above. If I had, you could see how easy it is to use, by aligning reflections of nearby objects with charts of the time of day in each month of the year, directly below the semi-reflective, semi-transparent dome.
Larry Tafoya, head of the Electrical Department, inspects the charge controller or the inverter, both of which are mounted on the front of the same panel. To his left, Ben Thornton does something, but he is in too little light for the little camera in my phone to show exactly what he is doing.
Rear view of the same eight panels. Two electrical leads descend from a box near the top of each panel. The narrow vertical black lines on the top horizontal metal beam are Zip Ties, holding the module wires in place and out of view, thanks to David McDaniel. The grey rectangle attached to the wooden post is a "combiner box" where four pairs of series-connected panels are connected in parallel. AWG 2 wires in the grey conduit leading out of the combiner box and through the bottom of the wall carried DC power to the charge controller and the rest of the components.
The grey conduit running into the bottom of the lighter grey junction box encloses two gauge wires from the array of solar panels. When the switch with the red handle was in the "ON" position, the panels delivered 34.4V and 19.2A around noon, as shown in picture #12.
To the left of the main D.C. Disconnect for the power from the Photovoltaic Array (PV Array) are two pieces of the control equipment, manufactured by Outback (http://www.outbackpower.com/)
Typical home electrical outlets such as the one at the center of this picture (bottom right of the large grey box) require AC power, which is provided by the Outback inverter, partly included black box on the far right.
Inverter is the larger black device, attached to the left side of the white box. To its right is the charge controller, which diverts power to the backup battery array, opposite side of the particle board and not pictured because they just look like a bunch of automotive batteries.
Closer view of inverter and charge controller
The charge controller shows potential (Volts) and current (Amperes) of Input (PV Array) and Output (battery backup, loads or utility sell-back, after batteries are charged and usage is below Input from PV Array)
All connections the installer needs to make are well labeled.
The leftmost meter tracks consumption, like on any utility electrical setup. The next one measures electricity sold back to the utility company. Yay!!
The white tape near the bottom reads "R.E.C. (for "Renewable Energy Credit") Meter"
To pass inspection and receive renewable energy tax credits, notices like these are required in several places.
Ben Thornton is pictured here, taking a picture I believe. He is also obscuring most of Larry Tafoya. Further to the left of both, Jim Kalogeros-Chattan looks at the Renewable Energy Credit meter while multiplying $0.13 * zero in his head. :-) When class was dismissed on Friday, we were not sure whether the controller needed to be re-programmed, or whether the batteries just needed to be fully charged before power would begin to flow from our array to PNM, the local electric utility. We did not get our Ferris Bueller moment of seeing the meter run backward. I suspect both are Hollywood special effects.
Wiring diagram of the fully connected grid-tie system with battery backup
Second picture of same wiring diagram I did not want to have to try to re-construct this from memory!
