The objective of this project was to supply the +24V supply to a series of AREDN nodes from a 12V source, which is supplied by a power supply or backup battery. The PCB was home grown; the DC-DC converters were purchased, and the DC breakers and meters are boat parts, all are available online. The front panel was built by Front Panel Express.
The 802.11af standard is used for DC injection for ethernet connections of 100Mb/s or less. These networks only use two pairs, one for transmit and one for receive, on pins 1&3 and 2&6, leaving 4&5 and 7&8 unconnected. These are used for the power supply, 4&5 are the positive supply, 7&8 are the negative.
The nodes require +24VDC, which is created by two DC-DC converters which run from the 12 V, enabling the system to be powered by a battery backup source as well as a power supply.
The breakers are rated at 12v and 5A, and are readily available online. The meters supply a voltage and amperage reading, and are normally used in marine applications. Care must be exercised as it uses a floating ground, which is not an issue is this application, as there is no common ground. One breaker is a main, the other for two branch circuits. Up to four nodes can be powered by this panel.
Click on the button below to download .pdf files, for gerbers please contact me.
The panel comes from a company called Front Panel Express. Please visit their web site and download their front panel designer software, its free. Contact me for the design files, as I cannot upload them here.
The parts are available on Amazon, a list of what you need is below:
|DC-DC Converter||Drok 300001 Micro LED DcDc Boost Converter||4.95|
|Breaker||Blue Sea Systems A-Series Toggle||25.95|
|Meter||Cllena Digital Multimeter Current Tester||24.99|