Good news for Exactpower owners
 

and future owners.

I had a pleasant and productive meeting today w/ Bob Schluter (Pres. - Middle Atlantic Products, Inc), and was informed that he is ready to begin repairing EP-15A's, on a case by case basis after determining what will be required to fix your unit. He wants to review further details with me to give to everyone, so please don't write them for repair authorization numbers just yet. I will keep you posted; it will only be a week or so.

Yes, there will be an EP-20A in the near future (probably next year.) Besides the 20A capacity, it will use the same highly efficient, patented waveform analysis and feed-forward correction amplifier, to provide perfect 120V 60hZ AC. It will have new, patented, turn-on protection circuits designed to eliminate the in-rush current problems sometimes suffered by the early model EP-15A's. In addition, it will have memory turn-off circuits to permit safe, soft, restarts after a power outage.

Stay tuned.
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How it works
 

To answer the many inquiries I continue to get about these units:

The Exactpower units are not power conditioners. They are not voltage regulators (although they incorporate voltage regulation) and they protect from power surges by taking the equipment offline rather than trying to block the surge.

And strictly speaking, they are not regenerators either. Like regenerators, they DO produce perfect AC power; i.e., a perfect waveform curve, without any line-borne noise at a constant 120VAC 60Hz. But they do so with near-perfect efficiency. Old-fashioned regenerators like those from PS Audio and APS are only about 50% efficient, which is why they get hot, and often require cooling fans.

Regenerators take AC wall power and convert it ALL to DC. Then the DC is used to create all new AC from scratch. This can be done with transformers and rectifiers, or in the case of heavy-duty industrial applications, with a motor-generator unit. It's a perfectly good but HIGHLY INEFFICIENT process, and certainly NOT very 'green' And, there's really no reason to start from scratch like that, because AT ITS WORST, the waveform of our utility power here in the US is 80% OK.

The patented Exactpower design uses a microprocessor to analyze the incoming (60 cycle per second) AC waveform; but at thousands of times per second. If that 20% or less I mentioned of the 60Hz sine wave is not smooth, or has noise on it, has voltage peaks or sags (compared to the ideal, by the microprocessor) that information is 'fed-forward' to an amplifier that corrects JUST THOSE PARTS THAT ARE OUT OF WHACK, and inserts JUST THOSE CORRECTED PARTS OF THE WAVEFORM back into the AC power cycle. It does not throw the baby out with the bathwater as typical regerators do.

I hope that answers everyone's questions.

nsgarch.......Just for informational purposes, the new PS Audio Power Plant Premier AC regenerator operates at 85% efficiency, which is a substantial improvement over their older designs which were in the 50% efficient range, and as such were unacceptable for me. The new PPP is only warm to the touch, even under substantial load, and though they are equipped with thermostatically controlled fans, I have never heard any of my three PPP's fans turn on.

BTW, it's good to see you posting on Audio Aficionado. I have found your posts to be interesting and informative.

Thanks for sharing this info, looks like an interesting product. Can you post a link for info, photo's, pricing etc.?

Hi Dan. Well that figure (85%) is, to be diplomatic, somewhat conditional :yes: - as hinted at in the recent Stereophile review: "Like earlier Power Plants, the Premier has a fan, but the amp runs far more coolly than its predecessors; the fan isn't expected to come on unless there's considerable sustained current draw." In other words, the less of its 1500W capacity you use, the higher the efficiency of the unit. This (sliding efficiency curve) is achieved by the use of a "tracking power supply" which provides less power when the total equipment/system draw is low. Exactpower doesn't have to do any of that stuff. It's basically passing the wallpower AC right through after surgically cleaning up any glitches it finds.

Bottom line, is that to eliminate noise, the PPP still still uses standard conditioning/regenerating circuitry, and can only make new AC to the degree it discards about 50% of the wallpower. So it's designed to make only as much really new AC as called for, which helps. But it still has to employ a Class A-B amp, whereas the EP, by contrast, uses a simpler and more efficient (at low 60Hz frequencies) Class D amp, just as powered subwoofers do.

Don't get me wrong. I'm not saying the PPP won't do the job. But it IS old technology any way you slice it. And more costly to operate.

- Neil

Neal.......I appreciate your response. I will have to look into the new EP-20A should it come to market.

US Blues.......Here is a link to the EP-15A that is no longer in production. ExactPower | EP15A

Please see my new thread under 'Power Conditioners' for repair information.

Neil
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