Lightning protection AND putting a receptacle on UPS

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That is the problem with common mode transients. For example, the transient can go down a battery powered wire, be same voltage on both sides of the battery, never be seen by battery, and proceed to destroy electronics. Replace battery with MOV protector to have same problem. The voltage is never seen by a protector connected across both wires. Common mode transients are created by lightning and by other events such as AC electric power line switching. The latter should be irrelevant since any protection for the former also makes all other transients (except NEMP) irrelevant.
In another event, the computer were powered off when lightning struck. Two computers were connected to point of use protectors. Transient was traced by replacing ICs - making computers work again. Transient only entered on AC hot wire. Adjacent protector shunted transient to safety ground wire at computer. Transient entered both computer motherboards. Exited via network cards (ground plane to network wire). Down to third computer. Out via third computer's modem to earth ground via the telco 'whole house' protector.
Point of use protector contributed to damage of adjacent and powered off computers by providing a common mode transient path from AC hot, around computer power supply, into computer motherboard via safety ground wire. BTW, it does not matter much whether computer is on or off as demonstrated by this example. To damage computer, the transient must bypass protection already inside a power supply.
What do typically destructive transient seek? Earth ground. Electronics is damaged when transient uses them as as path to earth which is why computer modems, fax machines, and portable phone base stations are often easiest to damage.
Ignoramus32515 wrote:

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w_tom, can you explain to me what is the exact scenario where such a common mode transient would occur. Does it apply to a lightning strike, if so, where would it strike. I would like to hear something a little bit more precise.
I find it a little bit difficult to visualize how exactly a common mode transient would actually happen. And I think that I do understand what is common mode, from my electronics experiences. What I do not see is just how it would realistically happen.
That would make following your suggestion a little bit easier.
thanks
i

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furthermore... I am beginning to question the assertion that a whole house surge protector is going to to anything worthwhile to protect my electronics.
http://www.powersystemsdirect.com/Panamax/Service_Entrance_Protector_Whole_House_Surge_Primax_gpp8005_55.php
`` No so called whole house protector is really suitable for electronics protection in home theater systems.''
If so, then the suggestions for a WHSP may be helpful for protecting my refrigerator, or some other motor loads, but it is fully beside the point as far as protection of my home theater stuff is concerned.
Whereas the APC UPSes that I am going to install, do offer various levels of protection, like conditioning, etc.
i
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Ignoramus32515 wrote:

http://www.powersystemsdirect.com/Panamax/Service_Entrance_Protector_Whole_House_Surge_Primax_gpp8005_55.php
By itself whole house protection is incomplete. It should be teamed with point source protection.
Why do you seem to be so set to go against standard practice? What everyone is trying to tell you is standard practice and it became standard practice because of experience.
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wrote:

Yes, so I do, in fact, need the protection of individual circuits.
i
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How does your telcos protect a computer connected to overhead wires everywhere in town? They use only 'whole house' type protectors AND expand that earthing system immensely. They don't put protector adjacent to electronics. Protector adjacent to electronics will not nothing effective because the earth ground is too far away. Therefore electronics suffers no damage during direct lightning strikes that occur every year in every town.
Your home entertainment system needs equivalent protection. Any effective protection adjacent to electronics is already inside those electronics.
Once you have enhanced the earthing for that 'whole house' protector, consider a series mode protector on the power cord. This is a major and expensive line filter that will also filter AC noise from the entertainment system. Brand names include Zerosurge, Brickwall, and Surgex.
But again, if you make conclusions from the gross half-truths promoted by APC, et al, then you also want to buy an East River Bridge - that may be available on sale due to a transit strike.
Don't believe for a moment that the APCs do significant line conditioning. They hype major claims - without numbers. IOW they may do some conditioning - and then charge tens of times more money for it.
If concerned for your household equipment, then start by expanding the earthing system - the most critical component for transistor protection. The one thing that makes the 'whole house' protector more effective.
Ignoramus32515 wrote:

http://www.powersystemsdirect.com/Panamax/Service_Entrance_Protector_Whole_House_Surge_Primax_gpp8005_55.php
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Hi Igor,
At 100% efficiency, a fully loaded 1/3HP motor will draw 2A (750 / 3 / 120V) _all_ the time, and many times that (probably > 15A momentarily) during startup.
Startup with a blower takes a long time.
[A blower motor is fully loaded all the time.]
But motors aren't 100% efficient. Fractional HP motors less so.
In reality, you're going to see at _least_ 3A continuously, more like 4-5A. I've seen 1/4HP motors with 12A FLA on the plate.
You need to check the plate rating on the motor.
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wrote:

Thanks Chris. The motor is hard to get to. Even if you are right, still, 3a is not too much for a big UPS.
i
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No. But I'm worried about a UPS surviving a 15-20A or more several cycle startup transient. If it can't "keep it up" (voltage), the startup takes longer, and the current draw is longer -> yet more agony for the UPS.
I'd be very hesitant about running 1/4+ HP motors on UPSes, unless they're _seriously_ beefy.
With motor-generators you have rotational inertia, and there aren't any semiconductors in the direct current paths. UPSes have no inertia. Lots of semiconductors right in line with the current.
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wrote:

Well, the only way to find it out is by trying, which I will do. I will start with my 1/2 HP Baldor grinder, which is a good approximation of a furnace blower (a lot of inertia).
i
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Actually, it isn't. blowers start under light load which rapidly builds to full load once it hits full speed. Grinders have virtually no load on them until you really lean into it with what you're grinding.
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wrote:

but they have a lot of inertia to overcome. My baldor starts relatively slowly.
i
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I found an interesting chart.
According to APC, a similar SUA2200 can run a 400 watt load for 1 hr 28 minutes. No doubt on new batteries.
http://www.apcc.com/products/runtime_for_extendedruntime.cfm
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Motor would have a much larger startup surge. Whereas electronics intentionally starve themselves on startup - have little startup surge - a motor will have a substantial startup surge. Try starting the motor with the UPS in battery backup mode. If motor starts even a tiny bit slower, the UPS is too undersized for that startup load and could be harmful to that motor. Motors (unlike electronics) don't like being starved for power on startup.
Ignoramus32515 wrote:

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Good point, I will try. In fact, I will try powering up my 1/2 HP Baldor bench grinder. It is a good approximation of a furnace blower.
i

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Actually it isn't. The bench grinder doesn't startup/operate under full load.
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wrote:

I think that its startup conditions are actually comparable.
i
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The grinder must start up with a load to approximate what the furnace motor is doing. Increased load on startup means a larger demand for current.
Ignoramus16420 wrote:

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What grid? Who said anything about a grid? What grid?
FDR wrote:

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For lightning protection your looking for UL-96a. For insurance you will need to have the installation inspected and receive a "Master Label". Lightning protection is not rocket science. But it is certainly not running an extension cord out to your Christmas yard lights either. You can buy the parts from several manufactures. HINT..... your going to need more than one ground rod. Lightning protection is a sacrificial path to ground. I can guarantee you even if you have a Master Label on the system if your house gets hit your going to have a lot more damage than a busted TV. I worked on a house in Prescott Valley that got hit. We tore every sheet of drywall off and all of the stucco. Replaced every piece of wiring and plumbing. Not much of a fire, just a lot of black lines on the stucco and drywall. Thank god they were not home. Every finial on the roof was gone and all of the down leads were zebra marks on the finish of the home. Yep on a hill out by itself.
A whole house surge protection device in the electrical service panel will, HELP....... Please check the SOARS book on grounding at your public library. Surge protection per the IEEE is done in zones. You must have 2 of the three zones covered/overlapped for "protection" . Third zone is the utility and their concept of protection is nothing that will do you any good.
Proper grounding of your dish and the underground cable feeding your home will, HELP...... This does not mean driving a ground rod out there. Unless you follow the "supplemental grounding" in the NEC. Ever wonder why they tell you stand with your feet together during a lightning storm?
Ain't no guarantees that after you install all of this equipment that it will even help.
Each site is different. Please consult local pros for advice before you start funding the bush economy.
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