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Now for solar panel installation
The first thing I needed to do was figure out what panels to buy. I ended up getting four Evergreen solar ES-190-RL panels. Each one puts out about 30.5Voc (oc = open circuit) so wiring two in series gets me within the 48 volt range (61Voc).I realized that the higher your panel voltage, the smaller your wire can be from the charge controller to the panels. In my case the charge controller is an outback MX60 and about a 50 foot run from the MX60 to the panels. At first I thought, well, if I wire all four panels in series I can get the voltage up to 30.5 x 4 = 122Voc and use much smaller wire  (smaller wire less expensive) from the MX60 to the midnight solar PV disconnect. But, you have to consider that the colder it gets (in winter especially ) the higher the voltage will be coming from the panels. The MX60 charge controller can handle only up to 150 volts max. After that, damage will occur. Also, the MX60 will stop operating when the PV voltage reaches 135v DC. Since wiring my 4 panels in series would give me 122Voc and considering that the voltage could easily get up to 135v I opted not to chance it and only wired 2 panels in series to get 61Voc. So, in conclusion, I have 4 panels, Ive grouped the 4 panels into two groups, each group of  2 is wired in series to get roughly 61Voc and both groups are then wired in parallel. Each panel is rated for 190watts. Watts devided by volts gives you amps (im using nominal voltage of 48v for calculating) So, 190 x 4 = 760 watts, 760 devided by 48 = 15.8333 so I used a 15 amp breaker for all four panels. You see an extra breaker on the right. It is turned off and is a spare for later.

You may be wondering, well if my battery voltage is 48 volts but my panels are wired for 61Voc, this does not add up  - right?. The reason is this, my battery bank is called a 48 volt bank ( batteries are 6 volts each x 8 = 48) but the batteries do not actually measure 48 volts exactly. If you refer to the chart below which was taken from Trojan battery's website you will see that my batteries (eight 6volt L16H's ) should have a daily charge of 59.2 and float of 52.8 and equalize of 62. In my case, I need the panels to reach the higher voltages in the 60's in order to properly charge the bateries to the manufacturer specifications (see chart below). Also, I want the panel and wind turbine voltages to be higher than my battery voltage so I can sell more power to the grid. My system (via configuration with the Mate) sells power back starting at 51.2 volts.
My batteries are at 100% full charge when they measure 51.2. Anything abouve 51.2 sells back to the grid and if I loose the grid then my batteries being at 51.2 will of course be fully charged. If you look at the second chart , each of my batteries (6 volt) should actually measure 6.37 volts at 80 degees.

Charger Voltage Settings for Flooded Batteries
 (taken from http://www.trojanbattery.com/Tech-Support/BatteryMaintenance/Charging.aspx)

 
System Voltage
Charger Voltage Setting
6V
12V
24V
36V
48V
Daily Charge
7.4
14.8
29.6
44.4
59.2
Float
6.6
13.2
26.4
39.6
52.8
Equalize
7.8
15.5
31.0
46.5
62.0


State of charge as related to specific gravity and  open circuit voltage

Percentage of Charge
Specific Gravity Corrected to
80o F
Open-Circuit Voltage
6V
8V
12V
24V
36V
48V
100
1.277
6.37
8.49
12.73
25.46
38.20
50.93
90
1.258
6.31
8.41
12.62
25.24
37.85
50.47
80
1.238
6.25
8.33
12.50
25.00
37.49
49.99
70
1.217
6.19
8.25
12.37
24.74
37.12
49.49
60
1.195
6.12
8.16
12.24
24.48
36.72
48.96
50
1.172
6.05
8.07
12.10
24.20
36.31
48.41
40
1.148
5.98
7.97
11.96
23.92
35.87
47.83
30
1.124
5.91
7.88
11.81
23.63
35.44
47.26
20
1.098
5.83
7.77
11.66
23.32
34.97
46.63
10
1.073
5.75
7.67
11.51
23.02
34.52
46.03


EVERGREEN SOLAR ES-190        MIDNIGHT SOLAR DISCONNECT

I used 1" rigid PVC for the DC feed  (#2 copper THHN) from the MX60 in the shack to the Midnight Solar disconnect seen above. I used 1/2" seal tight flexible conduit from the Midnight Solar disconnect to a 2 x 4 pvc box mounted to the bottom of the steel PV frame I had to weld which holds the 4 panels.
Also you can see to the right the midnight solar disconnect has a round DC lightning arrestor part number LA-302-DC. The one complaint I have about this disconnect is that when I installed the lightning arrestor, the door to the disconnect would not close all the way. I had to cut sort of a slight cresent out of the doors edge where the door starts hitting the round lightning arrestor. Basically the 1/2 inch knockout hole is a little too close to the front of the box. Moving it back a 1/4 of an in would be an improvement for this disconnect.

SOLAR PANEL mount

As far as grounding, I beat an 8 foot 1/2 inch ground rod into the ground beside the midnight solar disconnect. I grounded all four panels together ( as you can see above) with self tap screws and ground lugs to the PV aluminum frames and then to the  steel frame and then to the ground rod for lightning protection.
Another thing to point out is that the Evergreen panel wires all came with MC connectors on them. When I wired them up, all the wires that needed to terminate in the grey 2x4 box had their MC connectors cut off and then I used red and blue wire nuts to make the connection. You can buy MC connector junction boxes but I did not feel like spending the extra money. Besides, I had plenty of 2x4 boxes/connectors, and wire nuts.
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