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The electrical was one of the more complicated parts of this projects. I had originally thought it would be rather simple, just run some wires from the battery to the motor add a switch and that would take care of it. As I started to do so I realized it wasn't that simple. I needed to have gauges to measure the volts and amps of the battery, the wires needed to be correctly sized, and a switch for a 12V 60A system can't just be picked up at the local hardware store.

Lets start with the wire sizing. Wires are sized by gauge, the smaller the gauge the larger the wire. The Dayton 3/4HP motor pulls 58A according to the spec sheet. It turns out that a #6 wire is rated to handle 75 amps so that's what I used to connect the motor to the battery through the amp meter and switch (see wire diagram below). I used a 16 AWG wire to connect the voltmeter to the battery and a 16 AWG medium duty extension cord to connect the battery to the charging station. According to the extension cord label it could handle up to 13 amps. This should be more than enough for the .63 amps the solar panel puts out.

I found the gauges at a local car parts store. I wired the ammeter in series and the voltmeter in parallel. The ammeter helps to give me an idea as to the amount of amps I'm pulling when mowing the grass. This in turn gives me an idea as to how long the battery is going to last before needing a charge. The voltmeter tells me when I need to recharge the battery. According to the battery manufacturer the battery is fully charged when the voltage reads 12.7 V. When it reads 11.75 V the battery is down to 30% and needs recharging.

I originally wanted to use a breaker for the on/off switch but after searching for awhile I noticed that a 60A 12V circuit breaker is not readily available. Luckily I found a switch that could handle 60A at a local industrial electric supplier. I also added a 100A fuse between the battery and motor.

Solar charging station electrical:

I also used 16 AWG for the connections between the solar panel and the charge controller. I put a 1.5A fuse between the solar panel and the charge controller as specified by the manufacture.