We now have 12 port gigabit rack mounted injector panels - they are shielded, have a current limiter per port, current flow indicators, and dual power supply inputs for redundancy. We also have a 6 port, wall mount gigE injector. With many power supply options. they are on Amazon, eBay and at http:/...

There are also 4 port injector modules and 12 port rack mounted injectors with resettable fuses. There are also kits with the injector and a switching power supply. http://wifiqos.com

You might be exceeding the line length for the power you need. here is an online calculator to determine the line loss as a function of distance from the power injector to the load device. It will predict the delivered voltage after you enter the line length and the power needed by the device, and i...

here is an online calculator to determine the line loss as a function of distance from the power injector to the load device. It will predict the delivered voltage after you enter the line length and the power needed by the device, and it will calculate the power loss in the CAT-5. http://beyond-wif...

Here is a supplier that ships an 8 port injector from Texas:

http://beyond-wifi.com/poe/

It is available either stand alone or with 24v power supplies

there is also a calculator of line loss in the CAT-5 here http://beyond-wifi.com/poe/poe-calc.html