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<blockquote data-quote="Greg Cameron" data-source="post: 26272" data-attributes="member: 42">Re: Ebtech HumXI had a discussion with Bill Whitlock about this device, master of all things electric in audio. Basically what going on inside is that there is a pair of silicone diodes in parallel but in opposite directions between the ground in &amp; out. During normal use, the diodes don&#039;t conduct current until 600mV of juice is presented to them. So the ground &#039;looks&#039; open to potential ground loop currents. When there&#039;s a fault, the diodes close the circuit and pass the current. The problem, according to Bill, is that the diodes need to be able to conduct huge amounts of current during a fault until the breaker trips. In order to be totally reliable or close to it, he said the diodes would need to be the size of hockey pucks. The ones in there appear to be rated at around 5A which makes them a very risky thing to bet your life on in the event of an actual fault. There&#039;s a high likelihood they could vaporize before the over-current protection kicks in. The chance of getting a UL listing on those things is slim to none. And of course, they don&#039;t really solve the source of the problem. Just a bandaid, and a potentially dangerous one at that.FWIW, Bill is using this device as a slide in his current seminars on grounding as how not to do things.GregCu</blockquote>

[QUOTE="Greg Cameron, post: 26272, member: 42"] Re: Ebtech HumX I had a discussion with Bill Whitlock about this device, master of all things electric in audio. Basically what going on inside is that there is a pair of silicone diodes in parallel but in opposite directions between the ground in & out. During normal use, the diodes don't conduct current until 600mV of juice is presented to them. So the ground 'looks' open to potential ground loop currents. When there's a fault, the diodes close the circuit and pass the current. The problem, according to Bill, is that the diodes need to be able to conduct huge amounts of current during a fault until the breaker trips. In order to be totally reliable or close to it, he said the diodes would need to be the size of hockey pucks. The ones in there appear to be rated at around 5A which makes them a very risky thing to bet your life on in the event of an actual fault. There's a high likelihood they could vaporize before the over-current protection kicks in. The chance of getting a UL listing on those things is slim to none. And of course, they don't really solve the source of the problem. Just a bandaid, and a potentially dangerous one at that. FWIW, Bill is using this device as a slide in his current seminars on grounding as how [I]not[/I] to do things. Greg Cu [/QUOTE]

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