I have 4 KingWin 850W power supplies running at 600W each on 240VAC. Apparently the power factor correction circuit makes a bunch of noise and the power supplies have poor filtering. I don't know if all power supplies with power factor correction are this bad since I don't have any other active PFC power supplies.
I'm selling pass through type noise filters for
7 BTC ~1 BTC. There is a standard 120VAC plug and 12 AWG cord going in to a plastic box and the same coming back out to a 3 way outlet. There's about 1.5 feet of cord total. Another option is to buy a 5 - 15 uF film capacitor with across the line (X/X2/Y2) ratings and wire it in parallel with your outlet if you wanted a cheaper solution that should still help quite a bit. It would be nice if you bought the filter from me but please do something! The noise from these things can be quite awful. We have a meter that measures electrical noise up to 100 kilocycles in a unit called "GS". At the outlet of the miners it measured 1800 GS (1999 is limit of the meter) and under 60 GS is considered safe. The 120v outlets in the rest of the house came up to around 400 GS because of this.
This IS NOT electromagnetic pollution. The air in the house between you and the wiring creates a natural capacitor of so many picofarads. This is direct electric exposure of small amounts of current flowing directly through your body. There is no magnetic component involved.
I have had small black spots appearing all over my body during the past year since I started mining and I have never had something like this happen before. Having all those spots that I never had before suddenly start appearing everywhere in such a short time period was quite scary. There is a very strong possibility that it is directly related. I'm glad I found out what was doing it!!!! I think that 240V power wire that was running the miners runs right under the wall in front of my bed too.
Here's a copy of my ad in the order book:
One dirty electricity filter for BITCOIN MINERS using cheap unfiltered power supplies with noisy P.FactorC.. High frquency noise on your power lines is bad for your health! noise_voltage * frequency = how bad it is. 60cps * 240VAC is not as bad as 60,000cps at 1 volt. Don't learn the hard way like me. Contains 25uF of capacitance & 900uH of ind. total. Rated 30A 250VAC. Factory lead time 3 weeks.
edit: The noise at the miner outlets is now 800 GS and 400 GS on the filter input side. I was hoping for better. I guess the 2x450uH of inductance isn't enough even with 15uF of capacitance on the output and 10uF input. The rest of the house is down to about 110 GS.
edit2: I didn't want to center the conversation around the black spots thing. Lots of people have little black / grey spots on their skin. I didn't have such a thing until the last year which is why it was alarming to me.
Putting the spots aside, here is a collection of research about dirty electricity and the various health problems it can cause: http://www.stetzerelectric.com/category/research/ . I was planning to put some kind of filter on the mining power supplies anyway before I had ever thought there might be a connection with the spots and dirty electricity.There's a post below with a link to power supply inlet plugs with built in filters for only $5. You could add those to your power supplies and then add a 10uF X1/X2 rated film capacitor to the inside of your power strip along with a bleeder resistor. For four power supplies that would only cost you about $32 + shipping from Mouser.com. 2x450uH of inductance is still too small but it would help.
