generator_switchover

Raspberry Pi controller for switching on a generator when a solar battery bank as a voltage < 50v for an hour or until it reaches 57v.

Parts

Hardware

• Compute - Raspberry Pi Zero W
• uSD Card - 16GB NOOBS 3.0
• Relay + A/D - Pimoroni Automation pHAT
• Small Display - Adafruit Mini PiTFT 1.3"
• Break-away 0.1" 2x20-pin Strip Dual Male Header
• GPI Stacking Header for Pi

Cables

• Display - Mini HDMI to HDMI
• Power - 2.5amp 5v micro-USB
• micro-USB USB Hub

Libraries

• Python Library Automation Hat

Raspberry Pi Compute Setup

Below is the setup for the system, which will let you log in with ssh [email protected] on your local wifi network. The easiest way to do this is to first enable SSH and then log in remotely to do the rest so you can copy and paste.

00. Set up remote login

SSH

Enable SSH

sudo systemctl enable ssh
sudo systemctl start ssh

Now, make sure you connect to the same wifi network and try logging in with ssh [email protected] from your remote computer.

0. Set computer name, user/password and Wifi

We need to change from pi as the user and set a host name which makes sense. Usually this is a lot of menus so this simplifies it into a few scripts.

Hostname	generator
User	gen
Password	vine generator

Hostname

Change Hostname to generator with a script from the command line.

host_name=generator
sudo bash -c "echo $host_name | tee /etc/hostname"
sudo bash -c "sed -i -E 's/^127.0.1.1.*/127.0.1.1\t'\"$host_name\"'/' /etc/hosts"
hostnamectl set-hostname $host_name

User and Password

Change default pi user to gen and set password to vine generator

sudo useradd gen
sudo passwd gen
# enter "vine generator"
sudo usermod -aG sudo gen
sudo nano /etc/sudoers
# Add ALL            ALL = (ALL) NOPASSWD: ALL

1. Set up Wifi

This script will set or change which wifi you connect to on boot from now on.

curl -o ~/wifi_setup.sh https://gist.githubusercontent.com/rjsteinert/4999792f4a7aedd532b2/raw/6f7943aea1b38ad9e7c2fb4db76015c9b4a6b306/wpa2-wifi-connect.sh

# Put in your wifi and password here
sh ~/wifi_setup.sh SSID PASSWORD

Install a daemon which lets you see the localhost hostname rather than hunting for the local IP address.

sudo apt-get install avahi-daemon

sudo cat >> /etc/avahi/services/multiple.service <<EOL
<?xml version="1.0" standalone='no'?>
<!DOCTYPE service-group SYSTEM "avahi-service.dtd">
<service-group>
        <name replace-wildcards="yes">%h</name>
        <service>
                <type>_device-info._tcp</type>
                <port>0</port>
                <txt-record>model=RackMac</txt-record>
        </service>
        <service>
                <type>_ssh._tcp</type>
                <port>22</port>
        </service>
</service-group>
EOL

sudo /etc/init.d/avahi-daemon restart

ssh [email protected]

1. Base OS Update

# First time setup
sudo apt-get update
sudo apt-get upgrade
sudo apt-get install python3-pip
sudo pip3 install --upgrade setuptools

2. Setup I2C + SPI

https://learn.adafruit.com/adafruits-raspberry-pi-lesson-4-gpio-setup/configuring-i2c

sudo apt-get install -y python-smbus
sudo apt-get install -y i2c-tools

• Enable I2C - Run sudo-raspi-config then go to 5 Interfacing Options then I2C then ENABLE then exit.
• Enable SPI - Run sudo-raspi-config then go to 5 Interfacing Options then SPI then ENABLE then exit.
• Reboot - sudo reboot
• Test I2C - sudo i2cdetect -y 1 - And should see some
• Test SPI - ls -l /dev/spidev* - And should see some

Display

# https://learn.adafruit.com/circuitpython-on-raspberrypi-linux/installing-circuitpython-on-raspberry-pi

# https://learn.adafruit.com/pitft-linux-python-animated-gif-player/python-setup-2

sudo pip3 install adafruit-circuitpython-rgb-display
sudo pip3 install --upgrade --force-reinstall spidev
sudo apt-get install ttf-dejavu
sudo apt-get install python3-pil
sudo apt-get install python3-numpy

3. A/D + Relay

sudo pip3 install automationhat