|
Post by drbill on Aug 14, 2016 10:51:56 GMT -6
I'm getting a hugely ironic sense of "deja vu" happening..... Coincidence? I think not.
|
|
|
Post by drbill on Aug 14, 2016 11:00:49 GMT -6
Martin, the only way to guarantee nothing will happen from lightening is to unplug everything from the electrical system. keymod - agreed, but curious.... would throwing the breaker for your CRM sub panel in your main panel accomplish the same thing? thx.
|
|
|
Post by keymod on Aug 14, 2016 11:19:24 GMT -6
drbill, almost. Better than doing nothing. If the strike occurs upstream from your service, the disconnected/opened breaker will lessen the number of paths that the current can flow through but, given a strong/close enough strike, the current can still jump across the wiring connections inside the service panels and make it to your equipment. If the strike occurs downstream from your service equipment, actually hitting your building, all bets are off. So the key is to limit the path the strike can take. A properly designed and installed grounding path gives the lightening the path of least resistance with the hope being that it will choose to go directly to earth rather than through the premises.
|
|
|
Post by drbill on Aug 14, 2016 13:01:35 GMT -6
drbill, almost. Better than doing nothing. If the strike occurs upstream from your service, the disconnected/opened breaker will lessen the number of paths that the current can flow through but, given a strong/close enough strike, the current can still jump across the wiring connections inside the service panels and make it to your equipment. If the strike occurs downstream from your service equipment, actually hitting your building, all bets are off. So the key is to limit the path the strike can take. A properly designed and installed grounding path gives the lightening the path of least resistance with the hope being that it will choose to go directly to earth rather than through the premises. Awesome - thanks for the understandable and legit technical advise. <<thumbsup>> We have monsoon storms that roll in in the summertime @ 5500 ft altitude, and it can be white puffy clouds one minute, I go out to lunch and come back in a raging thunderstorm, so your advise is valuable to me. I may be working, jump out for a meeting - and won't power down and disconnect my stuff cause I'm coming back in an hour or two, and get back to see all hell breaking loose - the lightning is so erratic and random, that it could be a serious peril to gear. (Despite the fact that I have more than $1 per appliance protection LOL) LUCKILY - our power is underground, so the chances are better for me here than in LA where we were on 70 year old antiquated power grid with poles that were prone to failure. But....there's always the danger, and there are times its so gnarly that I can't even sit out on the front porch to watch it. Since I'm supposed to be responsible for my own grounding (LOL), I'm going to have my electrician check to see how far from the panel it goes into the ground.... And then of course there is the ground itself. All dirt is not equal......
|
|
|
Post by keymod on Aug 14, 2016 14:54:32 GMT -6
How far from the panel doesn't matter. What matters is where the grounding electrode conductor(s) are attached to the system. The NEC requires that the system is grounded at the main disconnect, which is not necessarily in your panel. At the main disconnect, neutral is tied physically to earth ( ground ). Everywhere else in the system, it must be separated. So the grounding conductors in any panel which is a sub-panel and/or in any panel which doesn't include the main disconnect, must be on a separate buss/rail/point of attachment from the neutral. We are required to provide two grounding electrodes ( rods ) which are eight feet long, 5/8" diameter copper-coated steel, driven into earth approximately 8 - 10 feet apart, as vertically as possible. These are connected together , back to the main, using one grounding electrode conductor, un-broken. As for the dirt, there is a minimum resistance, in ohms, which is supposed to be provided by the grounding electrode system. I'd have to look that number up in the NEC. There are ways to improve that number if needed, but I've never seen any Inspector check for it here in CT. I guess it's assumed our dirt is dirty enough..... Florida has trouble with this because of it's sandy soil. Any metal cold water piping within the premises has to be grounded back to the main. If there is PEX mixed with copper, the PEX has to be jumpered. Same for any metallic gas lines, even the flex stuff. There are some manufacturers of the flex who have U.L Listing stating their product does not have to be grounded, but most municipalities require it anyway. Better safe than sorry, lightening and short-circuits don't mix well with gas. We are now even required to ground the rebar within the footings of a home, and all metal within a commercial building. One of the best things your electrician can check is to make sure all of the connections within a panel, especially the neutrals, are properly tight. Neutral is a current-carrying, grounded conductor ( back at the main disconnect, remember? ) Therefore, a loose neutral may hinder stray current making it back to earth. Current ALWAYS wants to go back to the earth and, if it can't get there the way it's supposed to, it will find other means. That's where things can go badly, at the speed of light.
|
|
|
Post by keymod on Aug 14, 2016 14:57:18 GMT -6
So, a direct question ... from a musician, who's not an electrician or engineer: For a home studio (2 car garage turned into "state-of-the-art" room), how/what can I obtain/do to solely protect the equipment from power anomalies? What can you recommend? Are you already built-out, or just starting to plan?
|
|
|
Post by drbill on Aug 14, 2016 15:05:54 GMT -6
How far from the panel doesn't matter. What matters is where the grounding electrode conductor(s) are attached to the system. The NEC requires that the system is grounded at the main disconnect, which is not necessarily in your panel. At the main disconnect, neutral is tied physically to earth ( ground ). Everywhere else in the system, it must be separated. So the grounding conductors in any panel which is a sub-panel and/or in any panel which doesn't include the main disconnect, must be on a separate buss/rail/point of attachment from the neutral. We are required to provide two grounding electrodes ( rods ) which are eight feet long, 5/8" diameter copper-coated steel, driven into earth approximately 8 - 10 feet apart, as vertically as possible. These are connected together , back to the main, using one grounding electrode conductor, un-broken. As for the dirt, there is a minimum resistance, in ohms, which is supposed to be provided by the grounding electrode system. I'd have to look that number up in the NEC. There are ways to improve that number if needed, but I've never seen any Inspector check for it here in CT. I guess it's assumed our dirt is dirty enough..... Florida has trouble with this because of it's sandy soil. Any metal cold water piping within the premises has to be grounded back to the main. If there is PEX mixed with copper, the PEX has to be jumpered. Same for any metallic gas lines, even the flex stuff. There are some manufacturers of the flex who have U.L Listing stating their product does not have to be grounded, but most municipalities require it anyway. Better safe than sorry, lightening and short-circuits don't mix well with gas. We are now even required to ground the rebar within the footings of a home, and all metal within a commercial building. One of the best things your electrician can check is to make sure all of the connections within a panel, especially the neutrals, are properly tight. Neutral is a current-carrying, grounded conductor ( back at the main disconnect, remember? ) Therefore, a loose neutral may hinder stray current making it back to earth. Current ALWAYS wants to go back to the earth and, if it can't get there the way it's supposed to, it will find other means. That's where things can go badly, at the speed of light. Great practical info!! Thanks!
|
|
|
Post by formatcyes on Aug 14, 2016 15:18:49 GMT -6
I am an electrician and telephone/data/security tech The only way to protect your equipment from lighting strikes is to unplug it no if's or butt's. I could tell lots of horror stories from the tropic's of having to fix multi million dollar pieces of equipment where the lighting protections only real use was to show where the current went. Don't waste money on lighting protection simply unplug your gear if a storm is about simple and cheap..
|
|
|
Post by drbill on Aug 14, 2016 15:52:04 GMT -6
Don't waste money on lighting protection simply unplug your gear if a storm is about simple and cheap.. And for me, completely unpractical. If it fries, it fries, but I'm going to throw whatever I can at it to protect it - I can't stop working. I'd have to unplug my stuff all summer and half the winter to be completely "safe". Cause we can get a close strike out of the blue, almost with sunny skies. Weather can completely change 3-4X's a day. You never know when it's going to hit.
|
|
|
Post by aremos on Aug 14, 2016 16:02:57 GMT -6
So, a direct question ... from a musician, who's not an electrician or engineer: For a home studio (2 car garage turned into "state-of-the-art" room), how/what can I obtain/do to solely protect the equipment from power anomalies? What can you recommend? Are you already built-out, or just starting to plan? Already built-out! BTW I asked the following & no one responded: The power utility company here in South FLorida (FPL) is offering a surge protection program for $10./month. Is this worth it? (A device installed under the meter, etc.)
|
|
|
Post by drbill on Aug 14, 2016 16:12:33 GMT -6
If they offer any kind of insurance and back it up, I'd say the $10 a month is worth many times that and I'd personally sign up in a heartbeat. But my experience with the electrical companies when things blow up due to outages, storms, etc. is pretty dismal - at least in terms of getting any kind of compensation for fried gear. They tend to believe like westom - there's no problem. It's all in your imagination - or you personally did something wrong, because they believe like he does. I know of other people who have gotten payments for catastrophic gear frying out of them, but I never could. In the above scenario, if they just install a surge protector, and don't offer any kind of "insurance" if it doesn't protect you, you can do the same yourself for less (longterm).
|
|
|
Post by jcoutu1 on Aug 14, 2016 16:13:53 GMT -6
|
|
|
Post by drbill on Aug 14, 2016 16:27:46 GMT -6
This is what I put on the main house panel : store.acousticfrontiers.com/Environmental-Potentials-EP-2050-Whole-House-Surge-Protector.htmlI know I could have done cheaper. And this as the main Control Room sub panel for doubled up protection. store.acousticfrontiers.com/Power-Conditioners/Hard-Wired/SurgeX-PF-420-Surge-Protector-Power-Conditioner.htmlAgain, saving a few hundred dollars was not the main thing for me. Going with sage advice from known studio contractors and designers as to what has worked well in other studio situations (not with appliances or houses or data sites or commercial stores) WAS my primary concern. Jeff Hedback has had good luck with these and highly suggested them. One problem averted saves 10X's the cost. I'm sure westom (yeah, we know who you are westom heh heh) will say I foolishly wasted my money. Matters little to me as it gives me peace of mind as I will also pursue other practical advice as much as possible... (good grounds, unplugging gear when away from studio for any length of time, etc..)
|
|
|
Post by keymod on Aug 14, 2016 16:54:49 GMT -6
Aremos, I agree with drbill. No insurance, no rent. Jesse, Seimans makes a good product. I use their stuff but have not seen that one. The ones I use are in the $200 range that I get through my supply house. That colored Regional Zone thing seems Like Home Depot marketing. Why not just get the best one regardless of where you are?
|
|
|
Post by formatcyes on Aug 14, 2016 22:33:05 GMT -6
Don't waste money on lighting protection simply unplug your gear if a storm is about simple and cheap.. And for me, completely unpractical. If it fries, it fries, but I'm going to throw whatever I can at it to protect it - I can't stop working. I'd have to unplug my stuff all summer and half the winter to be completely "safe". Cause we can get a close strike out of the blue, almost with sunny skies. Weather can completely change 3-4X's a day. You never know when it's going to hit. In a professional situation you don't have a choice I agree. Lightning protection will help on the edges but if you get a half decent strike all bets are off and in your situation do your best and get on with your work no point worrying about what you cannot prevent. For us amateurs unplug and wait till the storm passes
|
|
|
Post by westom on Aug 15, 2016 8:48:06 GMT -6
The power utility company here in South FLorida (FPL) is offering a surge protection program for $10./month. Is this worth it? (A device installed under the meter, etc.) One of so many examples of 'whole house' protection. That protect or is properly sized. However the item that does protect ion is earth ground. Only a homeowner is responsible for that. Another does not understand the meaning of 'responsible'. Any kid can inspect earth ground. A homeowner who cannot must hire someone to perform that inspection. In business law, that someone is an 'agent'. A water pipe earth ground is no longer sufficient - even for human safety. That earth ground to also provide transistor safety must exceed code and human safety requirements. Only visual inspection can determine what is sufficient. A utility provided protector will continue to connect surges to earth for decades - if properly sized. Protection during each surge is defined by a connection to and quality of earth ground. Only a homeowner is responsible for inspection of and maintaining that other component of the surge protection 'system'. Once installed, nobody else inspects it unless the homeowner pays for or requests it. Since a 'whole house' protector can be purchases for $60 or $100 (to have protection for decades), then is it better to spend $10 every month? Well some have landlords who hate change. Then a utility installed protector is a better option. BTW, unplugging, power off, or open circuit breakers obvious are an ineffective and bogus solution. Since it requires one to know a stray car, lineman, tree rodent, or utility switching will occur long before the anomaly happens. Even power off or open circuit breakers leave appliances connected to a surge. This technique means one must never take showers, never leave the house, never sleep, and never have a job. Rediculuos when $1 per protected appliance makes all that and an ineffective solution unnecessary. Even the utility's $10 solution is vastly superior to what some have recommended.
|
|
|
Post by westom on Aug 15, 2016 9:02:28 GMT -6
Shame is that you spent so much money for a tinier protector. A minimal 'whole house' protector is 50,000 amps. That can be purchased for as little as $60 from companies of integrity including Cutler-Hammer, Leviton, Erico, Polyphaser, Siemens, General Electric, and many others. A protector in a sub panel is ineffective without an earth ground. Sub-panels typically have no low impedance connection to earth (many electricians do not know what impedance is). Protector for a sub panel must have a low impedance (ie less than 3 meter) connection to earth. So that protector is designed differently. That (your) protector may be of that type. Which would explain why it cost so much more money. But this (not the protector) should have most of your attention if you want and if recommending protection. The earth ground and its connection. How does that surge make a low impedance (ie less than 10 foot) connection to single point earth ground? Some recording studios have an earthed room located inside and separate from an earthed building. That means two layers of protection. It is effective. And it is expensive.
|
|
|
Post by jcoutu1 on Aug 15, 2016 12:46:26 GMT -6
We had a storm here Saturday night. It was the worst lightning storm I can remember. My gig ended early and I tried to beat the storm home, got caught in it. Strong rain, but constant lightning. Wild stuff. We were lucky, but this guy wasn't... www.talkbass.com/threads/my-worst-case-scenario.1238499/
|
|
|
Post by keymod on Aug 15, 2016 16:09:56 GMT -6
The NEC only requires ground rods to a sub-panel if it is within a separate structure from the main disconnect of the entire service. To do or recommend otherwise is dangerous and against code regulations.
|
|
|
Post by jcoutu1 on Aug 15, 2016 16:28:18 GMT -6
The NEC only requires ground rods to a sub-panel if it is within a separate structure from the main disconnect of the entire service. To do or recommend otherwise is dangerous and against code regulations. I assume the code is different in whatever country he is in.
|
|
|
Post by drbill on Aug 15, 2016 18:07:56 GMT -6
The country of Kalifornia? PS - glad you got thru your storm OK. Horrible story of that other guy....
|
|
|
Post by jcoutu1 on Aug 15, 2016 18:26:50 GMT -6
The country of Kalifornia? PS - glad you got thru your storm OK. Horrible story of that other guy.... Most Kalifornians don't mention meters and feet in the same paragraph. If you're trying to insinuate that is Tony in disguise, I highly doubt that too. He would have at least given me straight answers to my questions instead of being offended by my words. Also, I think it's WAY more typing than he would be willing to do to bust balls. I'm glad we made it through too. I just heard that the furnace at my deceased grandmother's house caught on fire during the storm and woke my uncle who was in town for the first time this summer. If he wasn't there, the house would be ash. Scary stuff.
|
|
|
Post by formatcyes on Aug 15, 2016 22:05:16 GMT -6
The power utility company here in South FLorida (FPL) is offering a surge protection program for $10./month. Is this worth it? (A device installed under the meter, etc.) Since a 'whole house' protector can be purchases for $60 or $100 (to have protection for decades), then is it better to spend $10 every month? Well some have landlords who hate change. Then a utility installed protector is a better option. BTW, unplugging, power off, or open circuit breakers obvious are an ineffective and bogus solution. Since it requires one to know a stray car, lineman, tree rodent, or utility switching will occur long before the anomaly happens. Even power off or open circuit breakers leave appliances connected to a surge. This technique means one must never take showers, never leave the house, never sleep, and never have a job. Rediculuos when $1 per protected appliance makes all that and an ineffective solution unnecessary. Just no. You clearly don't know what you are posting about. You can build a lighting proof structure but it would have no conductors in or out. A shipping container with an internal generator and optic fiber connections would be quite happy while being hit with lightning. However if you bring in any external wiring (power or comms) and lightning strikes near by gear will get fried the 1.21 gigawatts has to go somewhere and if you think grounding your gear will help what do you think happens to the ground voltage when it gets hit??? You are more likely to be struck by lightening than win the lottery.. However the risk is still small. Your $100 surge protector is equivalent to putting up an umbrella during a meteorite strike.
|
|
|
Post by westom on Aug 16, 2016 7:56:11 GMT -6
The NEC only requires ground rods to a sub-panel if it is within a separate structure from the main disconnect of the entire service. To do or recommend otherwise is dangerous and against code regulations. You need to read what was written with better care. Described were products from responsible companies that can be located in a sub panel. In special installations, an earth grounded room is inside (isolated) inside a grounded building. Then that building has two protection layers. Then protectors inside a sub-panel (and protectors for other incoming wires) make a low impedance (ie less than 10 foot) connection to single point earth ground. But critical is the 'primary' protection layer (often found on a utility pole) and a 'secondary' protection layer (found at the service entrance). These two protection layers are sufficient for most everyone IF earth grounds are upgraded to both meet and exceed code and human safety requirements. Code says little to nothing about protecting transistors (appliances). Most of this stuff is little known to electricians. Electricians are only taught about electricity in terms of human safety and code. Concepts such as impedance, equipotential, etc are completely foreign to some electricians. Since transistor safety involved concepts that are irrelevant to human safety. Protection from direct strikes is routine; as was true more than 100 years ago. In each case, protection is defined by earth ground. A lightning rod is only as effective as its earth ground; to protect a structure. A protector is only as effective as its earth ground; to protect items inside that structure.
|
|
|
Post by keymod on Aug 16, 2016 8:34:29 GMT -6
Isolated ground is a completely different animal from service and equipment ground. With it, special wiring techniques are required . It's not something that can be added simply by connecting another ground rod to a sub-panel. Even the receptacles used have to be specific to use with it. And it's not something easily or inexpensively added to an existing installation.
|
|