Yes indeed! And also, the - of the LED is not the ground of the Niles chassis, so if you connect to, say, the IR input of a Lexicon preamp, the IR will not work if ANY other part of the IR system connects to your system's ground!

Xantech offers a visible LED with a cable and a mini plug on it for troubleshooting, or you can just get any old LED and put 330 ohms in series with it...it will tell you if a signal is there. With that resistance, you could connect to your signal bus, or to an LED output, or even to the 12 volt supply, and you will know immediately when voltage is present.