[TJS]

Hi guys, i already hv power distribution, and now im planning to add a noise filter, i hv no idea at all what kind of noise filter that i can put in between iec to all receptacles in my distribution, i found used noise filter like these:


I can used it in my power dist as my noise filter?

[Speedskater]

In general, filter's should be placed near the noise source or at your component.

This is a short Jim Brown applications note on a variety of Power Line RF Filters
http://www.audiosystemsgroup.com/PowerFilters.pdf

*************************************************
This is a rather long Jim Brown paper. 
Don't let the title fool you, it started out as an audio system paper then he updated it and added the Ham info.

"A Ham's Guide to RFI, Ferrites, Baluns, and Audio Interfacing"

by Jim Brown K9YC
Audio Systems Group, Inc.
http://audiosystemsgroup.com

The basis of this tutorial is a combination of my engineering education, 55 years in ham radio, my
work as vice-chair of the AES Standards Committee working group on EMC, and extensive research
on RFI in the pro audio world where I’ve made my living. That work is documented in technical
papers and tutorials that can be downloaded from the publications section of my website.
http://www.audiosystemsgroup.com/RFI-Ham.pdf

Many more Jim Brown papers and PowerPoints at:
http://www.audiosystemsgroup.com/publish.htm

[Folsom]

I'd go with Felix's for individual units to each componet (instead of a box, which gives better options). By using them instead of the one pictured, you can use high quality chokes instead of whatever is in that box.

[Speedskater]

With brand name filter's like Corcom, you can find response charts and they are safety tested.

[Speedskater]

Remember that power line filters are problem solvers. If you don't have the specific type of problem that the filter is designed for, then the filter adds nothing to your power quality.  Ham radio operators have an advantage here. Their receivers can measure the interference frequency and level,  then they can add a filter and re-measure it's level.

[Folsom]

Remember that power line filters are problem solvers. If you don't have the specific type of problem that the filter is designed for, then the filter adds nothing to your power quality.  Ham radio operators have an advantage here. Their receivers can measure the interference frequency and level,  then they can add a filter and re-measure it's level.

I'm going to disagree. To the point where this is the worst thing you've said. Why? Because there isn't a house on the planet that wouldn't benefit from a form of power conditioning. I don't care how low you think your noise is, the less the better. Not only that but your equipment generates noise and feeds it back in, so all the equipment can share.

I've mentioned it before, a guy at 6moons had 4% noise, dedicated circuits, as good as it gets... (probably had his house designed for this, looks like an expensive house) He immediately knew upon using an Audience Adept unit that he would NEVER bother listening to anything without a power conditioner again.

Are all forms equal? No.

[TJS]

I read all about felixs power cond today, it is so huge, my power distribution is compact in size

Its like this


Probably few fellows here can give me simple noise filtering idea?? Want to improve the ac power quality, thx

[Folsom]

You can work with that. X caps across the back of each, .1uf and 1uf. Then use a 17a choke at the begining if your load isn't high.

Another option is to make an inline unit to that. Inside of containing a few options ( like a choke and super-cap setup, it'd be a box the size of a DAC or so)

The best, while keeping that box, would be felix's inline after it. The advantage here is that the componets will feed less noise to eachother.

Feel free to PM me if any of this makes you uncomfortable. Stay safe with line voltages.

Oh and your ground wire looks less than 12ga. Are those sockets isolated ground? If so switch to star grounding.

[TJS]

You can work with that. X caps across the back of each, .1uf and 1uf. Then use a 17a choke at the begining if your load isn't high.

Another option is to make an inline unit to that. Inside of containing a few options ( like a choke and super-cap setup, it'd be a box the size of a DAC or so)

The best, while keeping that box, would be felix's inline after it. The advantage here is that the componets will feed less noise to eachother.

Feel free to PM me if any of this makes you uncomfortable. Stay safe with line voltages.

Oh and your ground wire looks less than 12ga. Are those sockets isolated ground? If so switch to star grounding.

I gonna used it for source preamp and power amp, is it better with choke or not? Cos i tuink load for amp gonna be high load. So the x cap for each outlet, combo between 1uf and 0.1uf? Even for outlet for power amp?

Yuuuppp...the ground wire too thin, planning to change it, better using star connection to ac inlet? Is it also better using star connection for hot line and neutral line to ac inlet?

Thx

[Folsom]

Yeah. I'd solder a 1uf and .1uf (.01uf if you want to get fancy with another) to some pieces of wire that you can clamp down on. You might want to relocate the sharing wires to the upper or lower screws to accommodated (they should have spots for two wires on each).

These capacitors will provide higher frequency attenuation for incoming and outgoing noise. So yes, even for amplifier. Technically you could do it for each socket if you broke off the tabs and got elaborate and tidy; but the amount of room you got makes that look challenging. It'd also benefit from having the mains come off a terminal strip instead of chained. I'm not sure if you have that much room, you might on the back panel, to attach a distribution system via some of those plastic screw terminals you can connect with jumpers. A choke could also be mounted to it. I'm not sure how much power your equipment uses, if I knew the amplifier I could probably comment to where a 17a choke would be appropriate or not. The nice 17a chokes from JW Miller are for common mode noise, and known to be uber transparent (like most low resistance chokes anyhow, SO LONG AS their amperage rating isn't being taxed).

The ground wire should only be starred IF the sockets have isolated ground. You can check this way,

1. unplug everything from the unit.
2. connect multimeter to ground pin on IEC or ground pin socket, and the other end touch it to the back strap, screws holding socket to case, or exposed metal case itself.
3. if there is a connection between the two, you don't have isolated and can skip star grounding.

Un-isolated receptacles "star" at the case, but the daisy chain is to allow a more direct, high current, low resistance, path back to the breaker panel. Starring at the case isn't an upgrade; I don't specifically recommend it for optimal use, but it works.

[Folsom]

Using multiple separate capacitors:

Ideally you'd use a lot of them (like in my units), way too many for this small case. By doing so you'd greatly increase the noise reduction. But there isn't room.

SO because you can't use a lot of them at once, you use them at varying values in order to not only increase the overall affects by adding another capacitor, but to vary the ranges in which they affect the most. Here's an inaccurate frequency range example.

1uf on a graph tugs noise down at 3mhz , .1uf tugs noise down at 6mhz, and .01 tugs down at 9mhz. (these are made up values)

By connecting a .1uf to a 1uf not only will you filter with a small increase at 3mhz and 6mhz, the overall affect will be greater for the entire frequency range affected (much wider than just their most effective range). If you connect .01uf you'll get a little more filtration at 9mhz, AND more over the entire spectrum affected by the capacitors.

 

It's a smart approach when dealing with very little room, and very little budget.

[TJS]

The ground wire should only be starred IF the sockets have isolated ground. You can check this way,

1. unplug everything from the unit.
2. connect multimeter to ground pin on IEC or ground pin socket, and the other end touch it to the back strap, screws holding socket to case, or exposed metal case itself.
3. if there is a connection between the two, you don't have isolated and can skip star grounding.

Un-isolated receptacles "star" at the case, but the daisy chain is to allow a more direct, high current, low resistance, path back to the breaker panel. Starring at the case isn't an upgrade; I don't specifically recommend it for optimal use, but it works.

i checked the connection between ground pin in IEC and the screw that holding the socket, it appears that there is NO connection, it means that i have un-isolated ground?? so i can "star" the ground in receptacles to the screw that hold the power inlet socket??

[Folsom]

If the case isn't grounded then you have isolated grounds on the recepticals. In this case I would star ground; but no not to the case via the screw that holds a recepticle. This could be done by connecting individual wires to the first socket ground or by makng a new ground point the IEC connects to then individual wires to each receptical.

Remember that's an optimal thing, and adding something like capacitors will make a more noticable difference.

You really should upgrade the ground wires to 12ga. 14ga would be acceptable if it's tinned.

Please don't do anything you're not comfortable with. Also feel free to take a photo to check work. You can PM me if you want to do something but don't feel comfortable on your own.