The Pi UPS Hat by MakerFocus is an uninterruptible power supply (UPS) add-on designed specifically for Raspberry Pi boards. This compact and efficient module ensures that your Raspberry Pi remains powered during unexpected power outages, preventing data loss and enabling safe shutdowns. It is particularly useful for applications requiring high reliability, such as IoT devices, servers, and remote monitoring systems.

• IoT Projects: Ensures uninterrupted operation of Raspberry Pi-based IoT devices.
• Home Automation: Prevents disruptions in smart home systems during power failures.
• Data Logging: Protects data integrity in logging applications by providing backup power.
• Remote Monitoring: Keeps remote systems operational during outages.
• Educational Projects: Demonstrates power management concepts in Raspberry Pi projects.

The Pi UPS Hat is designed to integrate seamlessly with Raspberry Pi boards, offering robust power management features. Below are the key technical details:

The Pi UPS Hat connects to the Raspberry Pi via the GPIO header. Below is the pin configuration:

1. Attach the Hat: Align the Pi UPS Hat with the GPIO header of your Raspberry Pi and gently press it into place.
2. Connect a Battery: Attach a compatible lithium-ion or lithium-polymer battery to the battery connector on the Hat.
3. Power the Hat: Supply 5V DC power to the Hat via the micro-USB port or GPIO pins.
4. Monitor Status: Use the GPIO pins to monitor power and battery status. Optionally, configure scripts to handle safe shutdowns.

• Battery Selection: Use a battery with a capacity between 1000mAh and 5000mAh for optimal performance.
• Safe Shutdown: Configure a script to monitor the battery status and initiate a safe shutdown when the battery is low.
• Heat Management: Ensure proper ventilation to prevent overheating, especially under high loads.
• Firmware Updates: Check the manufacturer's website for firmware updates or additional software tools.

Below is an example Python script to monitor the power and battery status using GPIO pins:

import RPi.GPIO as GPIO
import time

POWER_STATUS_PIN = 4 # GPIO4 for power status BATTERY_STATUS_PIN = 17 # GPIO17 for battery status SHUTDOWN_SIGNAL_PIN = 27 # GPIO27 for shutdown signal

GPIO.setmode(GPIO.BCM) GPIO.setup(POWER_STATUS_PIN, GPIO.IN) GPIO.setup(BATTERY_STATUS_PIN, GPIO.IN) GPIO.setup(SHUTDOWN_SIGNAL_PIN, GPIO.OUT)

try: while True: power_status = GPIO.input(POWER_STATUS_PIN) battery_status = GPIO.input(BATTERY_STATUS_PIN)

    # Check power status
    if power_status == GPIO.HIGH:
        print("Power supply is normal.")
    else:
        print("Power supply is disconnected. Running on battery.")
    
    # Check battery status
    if battery_status == GPIO.LOW:
        print("Battery is low! Consider shutting down.")
        # Trigger safe shutdown signal
        GPIO.output(SHUTDOWN_SIGNAL_PIN, GPIO.HIGH)
        time.sleep(1)
        GPIO.output(SHUTDOWN_SIGNAL_PIN, GPIO.LOW)
    
    time.sleep(5)  # Check status every 5 seconds

except KeyboardInterrupt: print("Exiting program.") finally: GPIO.cleanup()

• Install the RPi.GPIO library before running the script: pip install RPi.GPIO.
• Modify the GPIO pin numbers in the script if your setup differs.

1. The Raspberry Pi does not power on when using the Hat.

   • Ensure the battery is properly connected and charged.
   • Verify that the input power supply provides 5V DC and sufficient current.

2. The battery does not charge.

   • Check the battery connection and ensure it is compatible with the Hat.
   • Confirm that the input power supply is connected and functioning.

3. The Raspberry Pi shuts down unexpectedly.

   • Monitor the battery status using the GPIO pins to ensure the battery is not depleted.
   • Use a higher-capacity battery if your application requires extended backup time.

4. The Hat overheats during operation.

   • Ensure adequate ventilation around the Raspberry Pi and the Hat.
   • Avoid exceeding the maximum output current of 2.5A.

Q: Can I use the Pi UPS Hat with other single-board computers?
A: The Hat is designed for Raspberry Pi boards but may work with other SBCs that have a compatible GPIO header and 5V power requirements.

Q: How long can the Hat power my Raspberry Pi during an outage?
A: Backup time depends on the battery capacity and the power consumption of your Raspberry Pi. For example, a 3000mAh battery can provide approximately 2-3 hours of backup for a typical Raspberry Pi 4.

Q: Is it safe to leave the battery connected all the time?
A: Yes, the Hat includes built-in charging and protection circuits to prevent overcharging and over-discharging.

Q: Can I monitor the battery level programmatically?
A: Yes, you can use the GPIO pins to monitor the battery status and trigger actions based on the readings.

This concludes the documentation for the Pi UPS Hat by MakerFocus. For further assistance, refer to the manufacturer's website or community forums.