John,
The Blowtorch uses R core transformers, L and C passive filtering, and three stages of electronic regulation and filtering: a series regulator, shunt regulation, and a local cap multiplier. Do you hear the effect of a quality line conditioner, or line cord, or AC Bybees even after all this effort to isolate the active circuitry from line and load variations. Yes there will be a bun fight whatever you say
The Blowtorch uses R core transformers, L and C passive filtering, and three stages of electronic regulation and filtering: a series regulator, shunt regulation, and a local cap multiplier. Do you hear the effect of a quality line conditioner, or line cord, or AC Bybees even after all this effort to isolate the active circuitry from line and load variations. Yes there will be a bun fight whatever you say
The CTC Blowtorch preamp actually uses a low capacitance E-I transformer for each channel and gain section, so it uses up to 4 identical transformers in its power supply case. Two for line, two for Vendetta phono, if added.
We add a common mode choke, hi speed diodes, and multiple capacitance in each as well, then we apply 3 stages of active filtering, first an IC for hum suppression, then a discrete fet shunt regulator for transient suppression, and finally a fet based cap multiplier that is on each gain stage. We don't use MOV's so we could be subject to lightning based surges, but we have been lucky so far.
As far as line conditioning is concerned, we often feel that less is best, IF POSSIBLE. When I do add line protection externally, I usually use a 10uf 600V polypropylene motor start cap directly across the power line (fused of course) and a gas tube transient suppressor that has direct circuit breaker protection. A gas tube will not turn off without manual reset, so this is necessary. There are 100's of these units out in the world without any significant complaint, as Bybee once made these units commercially, about 20 years ago. I do use a line conditioner, but it is a very exotic unit from Bybee, and I do not really understand its operation.
This is a different approach from Richard and Demian. Their approach is 'brute force' and all situations covered that can be very necessary and useful. Jack's and my approach is 'simple' and perhaps exotic. It seems to work pretty well too in many cases.
We add a common mode choke, hi speed diodes, and multiple capacitance in each as well, then we apply 3 stages of active filtering, first an IC for hum suppression, then a discrete fet shunt regulator for transient suppression, and finally a fet based cap multiplier that is on each gain stage. We don't use MOV's so we could be subject to lightning based surges, but we have been lucky so far.
As far as line conditioning is concerned, we often feel that less is best, IF POSSIBLE. When I do add line protection externally, I usually use a 10uf 600V polypropylene motor start cap directly across the power line (fused of course) and a gas tube transient suppressor that has direct circuit breaker protection. A gas tube will not turn off without manual reset, so this is necessary. There are 100's of these units out in the world without any significant complaint, as Bybee once made these units commercially, about 20 years ago. I do use a line conditioner, but it is a very exotic unit from Bybee, and I do not really understand its operation.
This is a different approach from Richard and Demian. Their approach is 'brute force' and all situations covered that can be very necessary and useful. Jack's and my approach is 'simple' and perhaps exotic. It seems to work pretty well too in many cases.
There have been several products with large line to neutral caps and they work to a degree however they do draw a lot of current and can even cause heating in the connectors. The esr of the cap and its wiring as well as the layout will limit its effectiveness as a filter.
Power has a multitude of junk on it ranging from broadband pulses from SCR dimmers, harmonics from rectified loads, noise from brush type motors to RF pickup on the wires and power line communications from 2 to 30 MHz (the losses are too great to use much above 30 MHz on power). The peak current on the PLC can be 3-4A at 30 MHz so that's a lot of interference.
Also in most countries today power is two power conductors and a safety earth. However at the end of 100 feet (30M) those signals will tend to redistribute themselves and the safety ground may have a lot of junk on it.
Warning, an isolated ground that does NOT return to the panel ground is NOT a safety ground anymore.
A GFCI would also work as a common mode magnetic filter so it may be a good thing in the chain.
Do not use a gas tube directly across the line. Once ionized it take a while (several cycles at 60 Hz) do deionize and will be essentially a dead short across the line causing lots of excitement. And they are not as fast as an MOV at suppressing a spike. You can use one in series with an MOV of the right rating if you need to reduce C at that point. This is required for surge in some markets.
Power has a multitude of junk on it ranging from broadband pulses from SCR dimmers, harmonics from rectified loads, noise from brush type motors to RF pickup on the wires and power line communications from 2 to 30 MHz (the losses are too great to use much above 30 MHz on power). The peak current on the PLC can be 3-4A at 30 MHz so that's a lot of interference.
Also in most countries today power is two power conductors and a safety earth. However at the end of 100 feet (30M) those signals will tend to redistribute themselves and the safety ground may have a lot of junk on it.
Warning, an isolated ground that does NOT return to the panel ground is NOT a safety ground anymore.
A GFCI would also work as a common mode magnetic filter so it may be a good thing in the chain.
Do not use a gas tube directly across the line. Once ionized it take a while (several cycles at 60 Hz) do deionize and will be essentially a dead short across the line causing lots of excitement. And they are not as fast as an MOV at suppressing a spike. You can use one in series with an MOV of the right rating if you need to reduce C at that point. This is required for surge in some markets.
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As the saying often goes, One Ground to Rule Them All.
the bonding between the ground and neutral happens at the entrance panel, as required by law and physics. This is the ground, all roads lead to it. Anything bypassing it is unsafe and noisy.
You can make your ground have lower Z, use a UFER ground or such, but the bonding is at the entrance, and all connections lead thru it.
Cheers
Alan
the bonding between the ground and neutral happens at the entrance panel, as required by law and physics. This is the ground, all roads lead to it. Anything bypassing it is unsafe and noisy.
You can make your ground have lower Z, use a UFER ground or such, but the bonding is at the entrance, and all connections lead thru it.
Cheers
Alan
When it comes to motor start polypropylene caps, they are apparently internally fused, but we rely on the house ckt breaker IF a cap should fail as a back up.
I am not an expert like PMA in RFI, etc, but I did work full time at UL doing safety tests on a number of products. I do have some idea of safety, when it comes to design.
I am not an expert like PMA in RFI, etc, but I did work full time at UL doing safety tests on a number of products. I do have some idea of safety, when it comes to design.
It might be noted that in the not too distant past, CATV, telecom et al grounding was allowed at the point of entry. Finally, that has been changed in NEC so that those also must be grounded at the same power entry panel ground/earth point.
however, there are millions of homes with multiple ground points from past builds. The -7000 can help by using the ground on the CATV protection at the -7000 and all audio powered by same single ground at -7000.
View attachment Ground Current bypass.pdf
How much current can flow thru such multiple point grounds? My house has such older type grounding and so is measured as an example for you. Shown is 4.84 mA.
Those homes will need a CATV ground breaker installed in series with the CATV coax cable.
Often audio systems alone are fine but when a video system (home theater) is added, the multiple ground issue causes hum and interference and the sound is not as clear as before. This is why.
THx-RNMarsh
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@Richard,
If you recall, you mentioned it a few times before and posted it here also. I just can't find the post.
Here it is from your post:
My question is now as it was then. No one carries cores of that type even the big manufactures, as I've looked.
Cheers
Post Script: I did find a #47 Material, olive green (ui = 110) good for lower frequency applications, which explains why it was used early in the power entrance in the board but it wasn't olive green.
Here was my thread on it if anyone is interested. LINK
I was thinking of using a round copper pipe to create a large circle, then pour concrete over it, embedding it in the earth.
I've been told that this is the best ground one can have. Fact or Fiction?
Cheers,
Braze a copper pipe to a 12 inch wide, 20 feet long, steel I-beam. Then hire a heavy equipment operator to pound the I-beam into the ground with one of these. Attach wire, done.
Yes, i do recall. However, note there are several types being used in these power conditioners, not one.
-RNM
There are a lot of misconceptions WRT grounding and actual ground impedance. The only reason our typical house grounding system has any hope of an actual low impedance to 'ground' is the fact that there are so many effectively connected in parallel.
If you require actual local, low impedance to ground then deep earth grounding techniques have to be used. DEEP EARTH GROUNDING
There is plenty of info out there, just search 'deep earth grounding'.
T
Richard, thanks for your responses and info and agree that clean power is easy and instant nice improvement.
The annual local area verge recycling in underway and this wrecked solar convertor pcb was free for the taking.
This board contains useful filtering/protection stages and is ideal for removal of these pcb areas for DIY power conditioning stages.
This is one example, plenty of modern gear has high capacity line filters in particular air conditioning outdoor compressor units and washing machines.
AA battery for size reference in Pic 01 and red arrows in Pic 03 highlighting failed/vented electros right next to 2W resistors dropping relay coil voltage... exactly this arrangement is common fault, in audio caps too close to regulators is common also, when will designers learn !.
Dan.
Dan.
The annual local area verge recycling in underway and this wrecked solar convertor pcb was free for the taking.
This board contains useful filtering/protection stages and is ideal for removal of these pcb areas for DIY power conditioning stages.
This is one example, plenty of modern gear has high capacity line filters in particular air conditioning outdoor compressor units and washing machines.
AA battery for size reference in Pic 01 and red arrows in Pic 03 highlighting failed/vented electros right next to 2W resistors dropping relay coil voltage... exactly this arrangement is common fault, in audio caps too close to regulators is common also, when will designers learn !.
Dan.
Pretty much taken care of, most modern TV's have Toslink Optical output only.
Dan.
Ah a bit about beams! I beams are actually labelled as "S" then the web size and the weight per foot. So to get an 8" I beam flange width would require a 24" web and a weight of 121 pounds per foot. Also I beams are flat on the outside flanges but slope at 16&2/3 degrees on the inner sides.
Most of the steel beams used are "W" or wide flange beams. These are flat on both the inside and outside of the flanges and have a larger flange to width ratio. Thus being a slightly less efficient use of metal but much easier to fabricate into structures.
So a 20' S24x121 would make a good ground, it just might be a bit of overkill. A side effect of course would be using a pile driver to plant such a beam would probably damage the nearby foundations from the effort to plant such a beam.
I would stick to the standard arrangement of three 6' copper plated steel rods.
It is common that house earthing rods are directly below the house meter/breaker box and driven into relatively dry ground. IME relocation of the local MEN earthing rod into regularly watered garden bed 2m away from original location effected useful improvement.
Dan.
Every project where I have had a consultant specify a special grounding scheme has had problems! The usual understanding is to use a ground different than the building entrance ground and then to over size the copper wiring by some huge amount.
They do not understand the safety conductor even though tied to the U.S. Standard "Neutral" or now called the "Grounded Conductor" does have potential difference at all other points in the power distribution system.
Although it is often understood the "Neutral" carries current and will have some voltage drop, even the safety ground conductors will have a potential difference at every outlet.
That is because the safety ground conductor is run in the same overall jacket or conduit with the power conductors. So by capacitive and magnetic coupling voltage potential is introduced along the length of the run.
That is why in my installations the shields do not carry signal. They are also connected so that no safety ground voltage potential difference currents are conducted through them.
Howie has a different set of problems as much of the musicians' gear does use the shield to carry signal and through convoluted means is connected to the safety ground. Often multiple pieces at different places and voltage potentials.
One approach to minimize the voltage coupling is to use a twisted pair for the current carrying conductors and a straight wire for the safety ground conductor.
Of course using a shielded isolation transformer cleans up much of the power utilities' blessings.
They do not understand the safety conductor even though tied to the U.S. Standard "Neutral" or now called the "Grounded Conductor" does have potential difference at all other points in the power distribution system.
Although it is often understood the "Neutral" carries current and will have some voltage drop, even the safety ground conductors will have a potential difference at every outlet.
That is because the safety ground conductor is run in the same overall jacket or conduit with the power conductors. So by capacitive and magnetic coupling voltage potential is introduced along the length of the run.
That is why in my installations the shields do not carry signal. They are also connected so that no safety ground voltage potential difference currents are conducted through them.
Howie has a different set of problems as much of the musicians' gear does use the shield to carry signal and through convoluted means is connected to the safety ground. Often multiple pieces at different places and voltage potentials.
One approach to minimize the voltage coupling is to use a twisted pair for the current carrying conductors and a straight wire for the safety ground conductor.
Of course using a shielded isolation transformer cleans up much of the power utilities' blessings.
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They can only go by code. Typically they have little experience with low level ground loop problems and do not have the knowledge background to attack both simultaneously.
The big machines I am involved in have severe issues when code compliance is required. It can be done to meet both requirements, but an NEC trained person is not really prepared for the challenge.
Now I attack picovolt and femptoamp level loop issues. The biggest hurdles are the users do not realize that all their motion stuff is driven by pwm outputs. They think just running a green wire to any bonding point is good enough.
Jn
The big machines I am involved in have severe issues when code compliance is required. It can be done to meet both requirements, but an NEC trained person is not really prepared for the challenge.
Now I attack picovolt and femptoamp level loop issues. The biggest hurdles are the users do not realize that all their motion stuff is driven by pwm outputs. They think just running a green wire to any bonding point is good enough.
Jn
For experimental purposes only, you are allowed to deviate from NEC so long as safety is still recognized and dealt with. We (LLNL) have got exemptions before with appropriate interlocking safety systems to shut down automatically. Including approved/reviewed Safety Operating Proceedures.
Since we worked around lethal voltages, i had to be trained in CPR every year qualified or could not work on some projects. Even with the SOP, training and safty interlock systems, someone would do something really stupid. One guy, while the experiment was live and HV on, climbed over the barrier and did something with the machine ON. Then he walked out thru the closed, interlocked door. Shut the whole experiment down. red lights and noise makers go off. Geeez.
X-ray machine used to examine materials placed in a chamber did not have safety interlocks on the door and you just had to remember if the X-Ray machine was on or off before opening the chamber door and putting your hand inside. Some got BBQ'ed and had to have his hand amputated. Then saefty interlock was placed on the chamber doors. Kinda learning by trial and error back in the day. Lots of drama and mishaps back then.
At home, it is best to go by NEC. And, dont buy any power conditioner which is not UL approved.
-RNM
Since we worked around lethal voltages, i had to be trained in CPR every year qualified or could not work on some projects. Even with the SOP, training and safty interlock systems, someone would do something really stupid. One guy, while the experiment was live and HV on, climbed over the barrier and did something with the machine ON. Then he walked out thru the closed, interlocked door. Shut the whole experiment down. red lights and noise makers go off. Geeez.
X-ray machine used to examine materials placed in a chamber did not have safety interlocks on the door and you just had to remember if the X-Ray machine was on or off before opening the chamber door and putting your hand inside. Some got BBQ'ed and had to have his hand amputated. Then saefty interlock was placed on the chamber doors. Kinda learning by trial and error back in the day. Lots of drama and mishaps back then.
At home, it is best to go by NEC. And, dont buy any power conditioner which is not UL approved.
-RNM
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