Overview

Managing multiple devices efficiently can be challenging, especially on a workbench filled with projects. This guide walks through integrating a used AP7930 PDU with Home Assistant. The AP7930 allows for remote control of power outlets and load monitoring, making it a great tool for power management, even though it’s likely overkill!

Selecting a PDU

Here are key considerations when selecting a PDU:

  • Input Voltage: Ensure it matches your power system (120V for most North American homes).
  • Plug Type: The AP7930 uses a NEMA L5-20P plug—you may need an adapter or a matching outlet.
  • Features: Look for metered (monitors power usage) and switched (remote on/off control) PDUs. These features may increase the PDU’s power consumption but are essential for automation.

Note: Always consult an electrician if you’re uncertain about power wiring and code compliance.

Performing a Factory Reset

The AP7930 reset process is tricky. Here’s a simplified method if the serial cable doesn’t work:

  1. Find the IP address using DHCP leases or Wireshark by filtering for the MAC address on the PDU label.

  2. If you can access the PDU via a browser using the default credentials (username: apc / password: apc), skip to the firmware update step.

  3. Install SNMP MIBs:

    sudo apt-get install snmp-mibs-downloader
sudo sed -i 's/mibs :/# mibs :/g' /etc/snmp/snmp.conf
sudo wget "https://fossies.org/linux/misc/netxms-4.1.377.tar.gz/netxms-4.1.377/contrib/mibs/PowerNet-MIB.txt?m=b" -O /usr/share/snmp/mibs/PowerNet-MIB.txt

  4. Verify the default SNMP string:

    snmpget -v 1 -c private $IP SNMPv2-MIB::sysDescr.0

  5. Set up a TFTP server to apply the following configuration (config.ini):

    [NetworkTCP/IP]
SystemIP = 0.0.0.0
SubnetMask = 0.0.0.0
DefaultGateway = 0.0.0.0

  6. Use SNMP to upload and apply the configuration:

    snmpset -v 1 -c private $DEVICEIP PowerNet-MIB::mfiletransferConfigTFTPServerAddress.0 s $SERVERIP
snmpset -v 1 -c private $DEVICEIP PowerNet-MIB::mfiletransferConfigSettingsFilename.0 s /config.ini

Updating the Firmware

To ensure optimal performance:

  1. Download the latest firmware here.
  2. Run the executable to update the PDU. If needed, you can manually upload the .bin files via FTP.

Securing the PDU

  • Change the default passwords under Administration -> Security -> Local Users.
  • Disable access for untrusted accounts.
  • Use SNMPv1 for Home Assistant (as SNMPv3 may not work with the default integration).

Configuring Home Assistant

To control the AP7930 via Home Assistant, update the configuration.yaml:

switch:
  - platform: snmp
    name: PDU Outlet 1
    host: your_pdu_IP
    community: your_community_string
    baseoid: 1.3.6.1.4.1.318.1.1.4.4.2.1.3.1
    payload_on: 1
    payload_off: 2

sensor:
  - platform: snmp
    name: PDU Load
    host: your_pdu_IP
    community: your_community_string
    baseoid: 1.3.6.1.4.1.318.1.1.12.2.3.1.1.2.1
    unit_of_measurement: A
    value_template: "{{((value | float) / 10) | float}}"
  • Switches: Control individual outlets.
  • Sensors: Monitor power consumption.

Restart Home Assistant, and you can now automate the PDU!

Conclusion

With the AP7930 PDU integrated into Home Assistant, you can remotely manage power outlets, automate switching, and monitor energy usage. This setup not only adds convenience but also optimizes power management on your workbench.