Originally Posted by alternety
My take on it: IP and EP are very similar except for the isolated ground thing.
Hi Alternety, they both accomplish the same goal but do it very differently. I've read some white papers by a 3rd party contracted by EP about their high frequency filtering ability vs. Cutler Hammer and it looks excellent. Though of course they did pay for it, so I'll take it for what it is.
Here's an execellent article on IT:http://powersurgeprotector.wordpress...f-a-protector/
Innovative uses more conventional design to accomplish their goal. The main shunt element is large MOVs shunting to ground. The biggest difference between them and say, Cutler Hammer or Square D is the use of an epoxy encapsulation. I actually bought one on the cheap off ebay and you can see it here, in black:
The article goes on to basically say, thanks to the dielectric strength of the epoxy, thermal expansion is negated so the MOVs are safe and sound for years and years under harsh conditions.
There's nothing really much on Eaton's site on what the Active Tracking Network is that filters out high frequency noise, but my educated guess is that its basically a very large implementation of NEMA's defination of Sine Wave Tracking, i.e. inductor chokes and large capacitors acting as RF/EMI filter. You can find these in most quality surge protectors.
The EP stuff is totally different in design. I've only found one other surge manufacturer that does something similar and they don't make whole house units. Marketing stuff aside, its basically a MOV (or other shunt devices) in parallel with a RLC circuit instead of the MOV shunting to ground. The magic is the L in the RLC which is of type nanocrystalline core making it very permeable therefore very high in inductance. Since the RLC circuit is a damping oscillator, it eventually dissipates the energy as heat from the resistor. They also seem to use some sort of epoxy as a dialectic and thermal conductor. This is all stuff I've learned from their patent. Doug Joseph, president of EP, has said similiar stuff in this old thread here:http://www.avsforum.com/avs-vb/showthread.php?t=277384
He uses a bit more marketing speak but the design and white papers I've read seem good. For instance the "spectrum multiplier" he talks about is what I think is an inductor, a device that basically stores power in a magnetic field and "trickles" it back out. The white paper where they subject the EP unit, a 80ka Cutler Hammer unit, and some other small manufacturer suggests this design also functions as an excellent filter.
I'd say if your ground is good with near 0 impedance and can can stay near zero as current rises any of the standard shunt to ground devices will be fine. That's everything from IT, Cutler Hammer, Leviton, Square D, Intermatic etc etc. If impedance rises as the current is shunted, the MOVs will experience thermal breakdown. The only thing you'd have to select from is how much it can handle (which also defines how long it will last) and if it has any sort of filtering. The IT design seems to be proven, the encapsulation epoxy really prevents thermal breakdown or runaway since they seem to last decades in their studies. That's why its my 2nd choice. Since I'm not sure about my ground and that residential grounding seems to be something of a pain in the ass, I'll likely go EP.
I'm sorry for the long post but I research a lot. No sales commission here, I'm just a software developer