I do not know much about networking, but I will still try to detail my issue as best as possible. I am a teacher, and over the past 3 years there has been a network box in my classroom. Inside the box one network switch (an HP 2910 POE) has been running with a continuous fan. It has not been a problem, since the fan is very quiet. A few days ago, they installed a second switch in the box (an HP 2920 POE) and an APC UPS unit. Those are the only three things in the network box drawing power. The problem is that the APS UPS has a continuous fan that is not too loud, but produces a continuous high pitch piercing noise. It drives you nuts when you are in the room for 5+ minutes. My students are going to go crazy taking an exam with that thing running next fall. I am curious if anything can be done about the fan noise on the UPS unit. Also, I wonder if we even need a UPS at all. Can a quick cut to the power (not a power surge, but a power outage) destroy those switches? If not having the APC UPS would just mean that the network isn't available during a power outage, then I do not think it is needed for my setting. I am curious to hear your thoughts. Thanks!
UPS Necessary in this Case?
- Thread starter michele
- Start date
The UPS not only provides back up power it also filters the noise off the line besides the obvious surge protection. My UPS is an ACP but doesn't have a fan. I would venture your hearing is some what like mine in I can hear dog whistles. The high pitched whine is the inverter that changes the battery power to AC power.
If you can hear it one of several things are possible.
You're hearing is sensitive to high pitched sound.
The inverter is running at max load.
The invertor transformer is bad and the coils are whining.
If it's a larger unit and has a fan it might be a bit of overkill. This is more suited to your needs > APC Back-UPS ES BE550G UPS - Newegg.com
If you can hear it one of several things are possible.
You're hearing is sensitive to high pitched sound.
The inverter is running at max load.
The invertor transformer is bad and the coils are whining.
If it's a larger unit and has a fan it might be a bit of overkill. This is more suited to your needs > APC Back-UPS ES BE550G UPS - Newegg.com
You are correct. A UPS has one function. To provide temporary and 'dirtier' power during a blackout. During normal operation, switches are connected (by the UPS) directly to AC mains. No filtering or power conditioning.
Second, if a fan make audible noise, then the fan is defective. Probably will eventually seize. Better informed techs read the specs for that UPS - know what its dB sound energy is BEFORE purchasing. Most techs have no idea. Most only hear the name APC. Then 'assume' quality.
Screeching obviously means a completely defective UPS.
Third, no UPS does hardware protection. That very popular myth comes from a subjective claim. The claim comes without a number. So near zero protection can be called 100% protection in advertising. The UPS only does not function - maintain temporary and 'dirty' power during a blackout.
So where are numbers for that claim? Well this 120 volt 'pure sine wave' UPS outputs 200 volt square waves with a spike up to 270 volts. Where is the 'pure'? From high school math: a square wave and spike are only sums of pure sine waves. Since they did not define 'pure' with a number, then many just *know* it must 'clean' power.
Some of the 'dirtiest' power those switches see come from a UPS in battery backup mode. And since all electronics are so robust, then even the 'dirtiest' UPS is ideal power for all electronics.
Eliminate a UPS if power loss does not cause data loss. That is a UPS purpose. To protect unsaved data from a blackout. Claims of hardware protection do not exist in that manufacturer's spec sheets. Claims of hardware protection are based only in hearsay. If untrue, then numbers are posted here to 'prove' protection. Many techs install a UPS due to hearsay; by ignoring spec numbers from the manufacturer. Do you really need that data protection?
So I guess the $70,000 connected equipment replacement warranty is a myth also.
APC and Trip Lite have been in the UPS and surge protection business longer than any one else. They make rock solid products you can plug your equipment in to and know your protected. (If you think I'm a fanboy let me confirm that for you)
I buy my UPS and Surge protectors after doing my homework on them. I don't know what happened to you westom to put such a sour taste in your mouth but what you have posted is mostly wrong.
APC UPS's do line filtering and surge protection as well as provide time when the power goes out, to do a graceful shut down of hardware connected to it. The power here where I live and work at is pretty nasty when viewed on an O scope. Coming out of the UPS is nice and clean.
As for the tech specs on Trip Lite and ACP products all you have to do is go to their respective web sites and click on the specs.
Now Michele the best course of action here is to leave the hardware alone. Contact the network admin and let them know the equipment is making a noise that is audible to you and it's distracting you and your class. Let them handle it from there. If you don't tell them they won't know there's a problem.
APC and Trip Lite have been in the UPS and surge protection business longer than any one else. They make rock solid products you can plug your equipment in to and know your protected. (If you think I'm a fanboy let me confirm that for you)
I buy my UPS and Surge protectors after doing my homework on them. I don't know what happened to you westom to put such a sour taste in your mouth but what you have posted is mostly wrong.
APC UPS's do line filtering and surge protection as well as provide time when the power goes out, to do a graceful shut down of hardware connected to it. The power here where I live and work at is pretty nasty when viewed on an O scope. Coming out of the UPS is nice and clean.
As for the tech specs on Trip Lite and ACP products all you have to do is go to their respective web sites and click on the specs.
Now Michele the best course of action here is to leave the hardware alone. Contact the network admin and let them know the equipment is making a noise that is audible to you and it's distracting you and your class. Let them handle it from there. If you don't tell them they won't know there's a problem.
Did you read their fine print? Good luck getting that warranty honored. It has numerous exemptions.
Or read the manufacturer specifications. Where does it claim to protect from each type of surge? It doesn't.
Or read its numbers. Destructive surges are typically hundreds of thousands of joules. How many hundreds of joules does that UPS protect from? Near zero.
APC and Tripplite are newcomers. An industry benchmark is Polyphaser. Other more responsible companies include ABB, General Electric, Siemens, Intermatic, Ditek, Leviton, Syscom, and Square D to name but a few. Homeowners could even obtain a 'whole house' protector from Cutler Hammer for less than $50 in Home Depot or Lowes.
Any protection on a power cord is already inside appliances. After all, what protects dimmer switches, clocks, refrigerator, furnace, and bathroom GFCIs? Your concern is the other and rare surge that actually causes damage. That overwhelms protection already inside appliances. Those protectors are rated to connect direct lightning strikes to earth (rated at least 50,000 amps). And remain functional. Effective protection means nobody even knew a surge existed because effective protectors do not fail or 'wear out'.
A 'sour taste' comes from people who never learned nor designed this stuff. How many direct lightning strikes without damage have you suffered? I did this stuff decades ago.
Michele - claims are hearsay. He provided no numbers. He never says why a UPS or power strip works. Ineffective and grossly overpriced products get promoted by a majority who are only trained in advertising. Anyone can search the internet for the so many victims who discovered what, for example, Newsman in 2002 posted:
Or Luke_Wilbur who saw what APC really does once he had that rare and destructive surge in 2009. Where was the protection?:
APC Battery Backup does not protect from power surge. - Consumer Complaints - DC Message Boards
Fire is another problem with these adjacent protector when not protected by one 'whole house' protector. Adjacent protectors need protection from the rare and actually destructive surge. A fire marshal describes why these undersized protectors cause fires:
http://www.esdjournal.com/techpapr/Pharr/INVESTIGATING SURGE SUPPRESSOR FIRES.doc
Or Norma describes in 2008 in "The Power Outage" what happens when an adjacent protector is unprotected:
We know an adjacent protector or UPS provides some protection. And then we include numbers. 99.5% of the protection is provided by earthing one 'whole house' protector. That is protection for everything for about $1 per appliance. Then we locate adjacent protectors on each appliance at maybe $25 or $80 per appliance. For an additional 0.2% protection.
So yes, that strip or UPS does protection. From a typically 'not destructive' surge. Those adjacent devices also need protection provided by earthing one 'whole house' protector. The word 'earthing' is critical. We also investigated and repaired damaged electronics by tracing the surge. By literally replacing individual semiconductors to make electronics functional for years. We learned this stuff the hard way - by designing protection systems and by traced surge damage directly traceable to human mistakes and ineffective protectors.
The superior solution protects everything for about $1 per appliance. Even the APC and Tripplite devices need protection provided by one properly earthed 'whole house' protector - provided by companies with superior reputations.
Excellent information on surges and surge protection is at:
http://www.lightningsafety.com/nlsi_lhm/IEEE_Guide.pdf
- "How to protect your house and its contents from lightning: IEEE guide for surge protection of equipment connected to AC power and communication circuits" published by the IEEE (the IEEE is a major organization of electrical and electronic engineers).
And also:
http://www.eeel.nist.gov/817/pubs/spd-anthology/files/Surges happen!.pdf
- "NIST recommended practice guide: Surges Happen!: how to protect the appliances in your home" published by the US National Institute of Standards and Technology
The IEEE surge guide is aimed at people with some technical background. The NIST surge guide is aimed at the general public.
Nonsense.
The author of the NIST surge guide looked at the amount of energy that could make it to a plug-in protector, even with a very near very strong strike to utility wires. The energy is surprisingly small - 35 joules max. (There are a couple reasons, if anyone is interested.) Any protector will have higher ratings than that.
Yes! Michele should install a 'whole house' protector in her school.
All these manufacturers except SquareD make plug-in protectors and say they are effective. Westom says plug-in protectors don't work.
SquareD says for their "best" service panel protector "electronic equipment may need additional protection by installing plug-in [protectors] at the point of use."
If you look up what Newsman said, the equipment was also connected to cable which did not go through the protector. As any competent manufacturer (and both surge guides) will tell you, all wires must go through the protector.
UL has, since 1998, required thermal disconnects for overheating MOVs. Any surge protector in the US should be listed under UL1449.
Nonsense.
Whatever was going on, from the description it obviously wasn't a surge.
If you look for the source it is the IEEE "Green" book. The 99+% figures are for lighting rods. The have nothing to do with surge protectors.
It is a post of misinformation from westom.
For real science read the IEEE and NIST surge guides. Excellent information. And both say plug-in protectors are effective.
For michele's question, I agree with setishock that the best idea is to ask network administrators, who should have the background to know what is appropriate in her classroom. It is not obvious to me why a UPS is needed.
http://www.lightningsafety.com/nlsi_lhm/IEEE_Guide.pdf
- "How to protect your house and its contents from lightning: IEEE guide for surge protection of equipment connected to AC power and communication circuits" published by the IEEE (the IEEE is a major organization of electrical and electronic engineers).
And also:
http://www.eeel.nist.gov/817/pubs/spd-anthology/files/Surges happen!.pdf
- "NIST recommended practice guide: Surges Happen!: how to protect the appliances in your home" published by the US National Institute of Standards and Technology
The IEEE surge guide is aimed at people with some technical background. The NIST surge guide is aimed at the general public.
Nonsense.
The author of the NIST surge guide looked at the amount of energy that could make it to a plug-in protector, even with a very near very strong strike to utility wires. The energy is surprisingly small - 35 joules max. (There are a couple reasons, if anyone is interested.) Any protector will have higher ratings than that.
Yes! Michele should install a 'whole house' protector in her school.
All these manufacturers except SquareD make plug-in protectors and say they are effective. Westom says plug-in protectors don't work.
SquareD says for their "best" service panel protector "electronic equipment may need additional protection by installing plug-in [protectors] at the point of use."
If you look up what Newsman said, the equipment was also connected to cable which did not go through the protector. As any competent manufacturer (and both surge guides) will tell you, all wires must go through the protector.
UL has, since 1998, required thermal disconnects for overheating MOVs. Any surge protector in the US should be listed under UL1449.
Nonsense.
Whatever was going on, from the description it obviously wasn't a surge.
If you look for the source it is the IEEE "Green" book. The 99+% figures are for lighting rods. The have nothing to do with surge protectors.
It is a post of misinformation from westom.
For real science read the IEEE and NIST surge guides. Excellent information. And both say plug-in protectors are effective.
For michele's question, I agree with setishock that the best idea is to ask network administrators, who should have the background to know what is appropriate in her classroom. It is not obvious to me why a UPS is needed.
I installed electronic security devices for over 25 years. Nothing and I mean nothing is going to protect you from a direct hit. Including a whole house protector.
I've walked in to homes after a direct hit with whole house protectors and what was currently available surge protection on my equipment. Door blown off the master control panel stuck in the wall on the other side of the room. Control board looked like a charcoal briquette what was left of it. 12volt 40va gel battery was shrapnel everywhere. If some one had been in that room at the time of the hit they would have been killed. The rest of the house was like a tornado went through there. Outlets fried. TV's with exploded tubes. Phones looked like some one had taken a hammer to them. All we found of the alarm clocks in the house were melted power cords. Every light was blown. The A/C was still belching smoke when I got there.
So you can go on about whole house protection being the ultimate way but I have seen with my own eyes they blow up as fast as anything else when confronted with mega amps from a direct hit.
As experience has taught me, nothing protects you better than common sense. When you get thunder boomers in your area, unplug as much as you can. Then go out and watch the fireworks show Mother Nature puts on.
I've walked in to homes after a direct hit with whole house protectors and what was currently available surge protection on my equipment. Door blown off the master control panel stuck in the wall on the other side of the room. Control board looked like a charcoal briquette what was left of it. 12volt 40va gel battery was shrapnel everywhere. If some one had been in that room at the time of the hit they would have been killed. The rest of the house was like a tornado went through there. Outlets fried. TV's with exploded tubes. Phones looked like some one had taken a hammer to them. All we found of the alarm clocks in the house were melted power cords. Every light was blown. The A/C was still belching smoke when I got there.
So you can go on about whole house protection being the ultimate way but I have seen with my own eyes they blow up as fast as anything else when confronted with mega amps from a direct hit.
As experience has taught me, nothing protects you better than common sense. When you get thunder boomers in your area, unplug as much as you can. Then go out and watch the fireworks show Mother Nature puts on.
So your town is without phone service for four days after every thunderstorm? Because their computer, connected to wires all over town, suffers about 100 surges per storm. And no damage?
When damage happens, correct failures created by protective equipment that ... and again read the spec numbers ... that does not even claim to protect from destructive surges. Too many waste time with magic boxes rather than learn what does protection.
No protector does protection. Either it connects low impedance (ie 'less than 10 feet') to what does protection. Or that protector is a protector that does not do effective protection. A completely different device that, unfortunately, shares a same name.
When damage happens, we inspect a protection system to locate that human created failure. Magic box protectors can even make damage easier. If a protector does not connect short to earth, then it only claims to protect from surges that are not destructive. It is that simple.
A case study demonstrates that. A Nebraska radio station suffered damage from direct lightning strikes. Their engineers had no idea how protection works. So they even disconnected critical grounds - only making damage worse. Read the case study. The entire solution - lightning strikes without damage - was only about fixing what does all protection. Not any magic box protector. They fixed the connections to and quality of earth ground:
Copper.org: Electrical: Power Quality - Proper Copper Grounding Stops Lightning Damage
Protectors that make direct lightning strikes irrelevant include a 'whole house' protector. Because they (and not the other device also called a protector) have the low impedance (ie 'less than 10 foot') connection to earth.
Your town has phone service every day after a thunderstorm because direct lightning strikes are made irrelevant by protectors connected as short as possible (ie 'less than 10 feet') to earth ground. A reality that has been well proven for over 100 years. That earth ground connection defines solutions that work verses solution that are ineffective. A protector is only as effective as its earth ground.
Michele needs a 'whole house' protector. Nothing inside the house or adjacent to appliances claims to protect from that type of surge. The building earthing may also need be upgraded to meet (and exceed) current codes. If not, then future damage is expected.
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