Line Conditioners

[Ducatista47]

Perhaps I am getting this all wrong, but is most of the concern here about surges and spikes from outside the house or business? If so, protect the service entrance first. From Square D:

"A damaging transient voltage can enter a facility from several locations. The highest level of protection should be provided at the service entrance. A second level of protection should be provided at distribution points serving critical areas, for example, computer rooms, accounting areas, and laboratories. Other facility entry points that should be protected include panels serving outdoor lights or outdoor equipment, such as motors. Protection should also be provided for critical areas with sensitive
equipment essential to the company."

Letting that crap into the house and then trying to keep it from your most expensive/sensitive gear while the rest of your home is vulnerable seems wrongheaded to me. I use that "second level of protection" too, but I would never rely on it alone, or to handle the really major threats.

Clark

[SEAWOLF97]

The highest level of protection should be provided at the service entrance.

so how do you go abt that with a standard house with standard electrical service ?

[Ducatista47]

so how do you go abt that with a standard house with standard electrical service ?

I touched on it in post #13. I have an ordinary home with ordinary three wire service. At the local Menard's I obtained a service panel surge protector, basically a whole house unit. (Square D SDSB1175C Load Center, the Surgebreaker Plus.)

It came with easy instructions and I installed it hanging off the bottom of the service panel (circuit breaker box). There is a green light to demonstrate its continued protection. The main unit of protection is a small replaceable module, two or three inches square. Huge, it should be noted, as compared to the units in all the equipment sold to home audio users. This particular unit also has protection built in for telephone and TV antenna and cable lines. The only other things that commonly enter a home, gas and water lines, are already completely grounded - the Commonwealth "earthed" is more descriptive here - and need no further protection, for or from. When I paid $200US for one, it was an awful lot of money for me, but I had wanted a whole house surge suppressor for as long as I could remember.

By the way, imho, Square D is the class act of electrical distribution, better than Cuttler-Hammer and Siemens. When we purchased this house I was happy to see a Square D QO (professional) series load center, better even than the Homeline series. When I wired my wife's Jacuzzi it was Square D from the box to the tub.

The products from Delta are less expensive and quite different, but very effective in their role. I really need to get one of their units. They used to market carbon blowout cans for lightning protection, if I remember right, but their current offerings seem like a really smart idea, silicon oxide varistors. Don't ask me, I need to do my homework too.

A caution. When working in a load center, do like the smart old timers did and keep one hand in your pocket. That way if you do become a ground, the circuit in your body will usually bypass the chest cavity.

Clark

[Ducatista47]

A couple of links about these devices. The more subtle units designed to handle smaller surges - not lightning - are known as Surge Capacitors. The heavier units serve as lightning arrestors.

http://todayztechnology.com/whatsnew.htm#SOVs

http://todayztechnology.com/WHY%20A%...0EFFECTIVE.pdf

What I am still figuring out is how to deploy these devices in the home circuit for maximum effect on spikes and surges generated inside the home, as from motors and compressors in our appliances and HVAC systems starting up and shutting off.

[SEAWOLF97]

The Furman conditioner showed up early today on my porch , unpacked and installed ...I dont know about all the features , but the EMI filters do work...

powered the woodstove fans up & down with nary a pop thru the 250ti's .... at least it takes that little worry of my list

the house was built in '59 and none of the outlets are 3 prong ...I've slowly been changing them out, but always wondered if they were properly grounded and had thots of another project ,, but the Furman supposedly will not light up the PROTECTED led , without a good ground,,it lit just fine.

[pinguin]

As Seawolf mentioned: A line conditioner may have a lot of features but at least an EMI filter should be installed. That's exactly what I need but a lot of things are very unclear to me. So I'd like to jump in with my questions. I'd like to apologize if they're somewhat simple but I'm not a tech:

Do manufacturers like Furman develop their specific filter design or do they simply use industry standard products? I assume the latter in particular for the cheaper conditioners (top of line is out of reach for me). May I ask those of you operating a conditioner about your experience? Did you have a look inside?

Here in Germany I know of some high end manufacturers that simply use industry standard filters give them a nice housing and sell them for a lot of money. E.g. products of Schaffner or Schurter can be found quite often inside. These companies publish all circuit details and filter attenuation on their websites:

http://www.schaffner.com/en/index.as..._id=12&dhtml=1
http://www.schurter.ch/products/emc_...language_id=10

All these filters are essentially a combination of inductors and capacitors. And the higher the current provided the less is filter attenuation in particular in the audible range between 10-20khz. See e.g. the FN2070 two stage filter

http://www.schaffner.com/components/...0%20e%2055.pdf

At 1 amp power level this filter provides very high attenuation but the 25 amp type gives much less. For one stage filters it's much worse for both low and high power capacity. So I fully agree with Scott. Filters in front of a power amp might not be that useful. You may oversize them to avoid a lack of power but there still may be a risk and their attenuation is low. Therefore my question to the conditioner's users: Did anyone check whether there is one filter for all outlets or has each outlet an individual filter? Several small filters covering 1-3 amp should do a better job than one for 10-20 amp. Additionally dirt created by a CD-player can't influence other parts of the system any more.

Now I've got some arguments for an individual filter in front of each device. But which one to choose when going with the industrial ones? I know the FN2070 mentioned above is used in audio applications. But what makes the difference to the FN2060?

http://www.schaffner.com/components/...0%20e%2054.pdf

Obviously the values of the installed capacitors and inductors are different but when comparing filter attenuation the graphs are very much the same. Could please anybody tell me why the FN2070 is preferable to the FN2060? I know the former is used in audio applications and the latter is not. But I don't know about the results. Additionally I've got the recommendation to choose the medical version without the Cy capacitors to avoid multiple grounding. Plausible at first glance but true? By this filter attenuation is worsened too.

Background of my question is that I have a professional monitoring/routing system as preamp having it's own filter on board. This one didn't harmonize with the filter I had in front of my whole system (and did a good job before). In the retrospect this is quite plausible: Capacitors and inductors can build up an oscillation circuit and in consequence sound may become awful. Therefore I'm searching for a solution hat provides each device with the appropriate filter. Could a line conditioner do the job? Or should I go with industrial filters and if so which type?

All helpful comments would be highly appreciated.
Ralph

[Ducatista47]

According to this site http://www.engineersedge.com/instrum...emi_filter.htm an EMI filter blocks radio frequencies generated by other equipment on the line or intercepted by power cords acting as antennas. Basically low pass frequency filters, you are correct that they do nothing for voltage regulation or surge protection.

Ideally, an EMI filter would be supplemented by voltage and surge protections and would be the least important of the three for equipment protection. I suppose if a solid state amp with an inferior power supply were used, and this category would include some very expensive gear, then an EMI filter might help prevent some sonic unpleasantness.

I suspect you are correct that most Power Conditioners are inexpensive off the shelf parts that perform these functions, in a nice looking box. Worse yet, they might not even offer some of the important protections, just cheap filters. I can't offer personal evaluations because I would never buy those boxes. I don't trust pretty cases that don't weigh much but cost a lot. Some might actually be worth the money, but I would think they would be industrial or professional products, not units aimed at the home audio market where hugely overpriced gear is the norm rather than the exception.

Let us recognize that home audio offers much opportunity for anyone who is willing to pay hundreds or thousands of dollars (or Euros) for a few dollars worth of electronics or wire. For wire, make that a few cents worth.

If your system is expensive, professional or important, I would suggest installing separate surge protection - off topic I realize - upstream, preferably at the service entrance; voltage regulation in a dedicated unit (these are good http://www.sola-hevi-duty.com/produc...ioning/cvs.htm and while a US division, a nice German company. For all I know they could be made in DE); and one of those inexpensive but good EMI filters that you already know about on the circuit for the audio electronics. I suppose some of the better off the shelf power strip type surge protectors might have an EMI filter built in, and the small surge protector included would be a nice secondary level of protection.

Edit: A quick look at APC's surge strips indicates that all models have EMI filters as well as surge protection. This puts the prices of much dedicated audio gear under suspicion, at least. An outlet surge protector is only one step up from a power strip. The Furman MX-8, for instance, offers only surge and EMI filter protection. In other words, equivalent to a good surge strip. In a pretty case.

Clark

[Ducatista47]

...to clear up myths and misinformation. Related to computers but generally applicable. Try this on for size:

"It has been claimed that common mode noise of levels of less than one volt on the AC power supplied to computer equipment can result in damage or malfunction. These claims are used to promote the sale of isolation transformers or "power conditioners". Closer analysis indicates that these claims are unfounded and not based on scientific fact." (From the second link) It goes on to demonstrate that any power supply with an isolation transformer can not transmit power line noise. So much for power conditioners for data equipment.


Some basic stuff

http://www.apcmedia.com/salestools/V...KLPK_R0_EN.pdf

http://www.apcmedia.com/salestools/A...3TSZ_R1_EN.pdf

http://www.apcmedia.com/salestools/S...NQZ5_R0_EN.pdf

http://www.apcmedia.com/salestools/S...NQYL_R0_EN.pdf

http://www.apcmedia.com/salestools/S...NQYQ_R0_EN.pdf


Ground Loops ("Inter-system ground noise is not the same as common mode noise")

http://www.apcmedia.com/salestools/F...3TLT_R1_EN.pdf

Watts vs VA

http://www.apcmedia.com/salestools/S...NQYF_R0_EN.pdf

Power Factor, Surge and Crest

http://www.apcmedia.com/salestools/S...NQYL_R0_EN.pdf

I think anyone reading this post will find the first, second and sixth links "must read." The first link banishes audiophile babel used to describe power problems by defining them in engineering terms.

Notice that while the end table lists "Power Conditioners" as solutions for voltage problems, they are referring to industrial units which include constant voltage devices. The audio units being discussed in this thread generally do not. (A look at the entire Furman line yielded only overvoltage shutdown protection on higher models, but no actual voltage regulation anywhere.) APC does have small stand alone CV units, so they are out there. When I was running a darkroom, I used the Sola industrial unit and I was not sorry. They keep voltage to within 1% of target.

While these White Papers are indeed sales tools, the source is strictly IEEE, not marketing departments. I triple E is the most trusted source of electrical and electronic knowledge in the world.

Clark