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Need good UPS
- Thread starter tako
- Start date
Be careful what you buy as you get different types of UPSs meeting different requirements.
http://www.sinetech.co.za/upsselect.htm
spiderz
Honorary Master
a cheep 1Kva or 600Va should do the job. They are sometime a bit slow with their switchover, but i haven't had problems yet. Battery life is +-2-3 years if your lucky.
The other option is a Online UPS. The don't switch over and permanently run off the battery. Normally used for servers and very sensitive equipment. They go thru batteries a bit faster and are hugely expensive.
The other option is a Online UPS. The don't switch over and permanently run off the battery. Normally used for servers and very sensitive equipment. They go thru batteries a bit faster and are hugely expensive.
recently lost my gaming rig (yay for insurance) so a bit paranoid at the moment.
the online models seem to start from around R4K... so i guess a decent line interactive and a good surge protection multiplug should do.. and keeping an eye out for highveld storms
the online models seem to start from around R4K... so i guess a decent line interactive and a good surge protection multiplug should do.. and keeping an eye out for highveld storms
HavocXphere
Honorary Master
APC brand is your best bet & priced accordingly.
Ideally you want a double conversion UPS. This will give near perfect lightning protection....but its about 3x your budget at least.
Second best is a line interactive UPS. It provide solid protection against dodge power quality & brown outs. However a direct/strong lightning strike will still nuke your PC. Effectively it takes a few milliseconds for the line interaction part to kick in...and a few milliseconds of 100k volts is enough to fry your PC.
If the UPS box does not say "line interactive" or "double conversion" then you really really don't want it.
Surge protection plugs are a controversial topic. I use them but don't have much confidence in them.
Best bet is to disconnect the PC.
EDIT:
@spiderz: I'd be careful with "Online UPS". Theoretically you are right that it should mean the same as double conversion. In practice this is not true. Some of the super cheap & rubbish ones are also marked "online".
Ideally you want a double conversion UPS. This will give near perfect lightning protection....but its about 3x your budget at least.
Second best is a line interactive UPS. It provide solid protection against dodge power quality & brown outs. However a direct/strong lightning strike will still nuke your PC. Effectively it takes a few milliseconds for the line interaction part to kick in...and a few milliseconds of 100k volts is enough to fry your PC.
If the UPS box does not say "line interactive" or "double conversion" then you really really don't want it.
Surge protection plugs are a controversial topic. I use them but don't have much confidence in them.
Best bet is to disconnect the PC.
EDIT:
@spiderz: I'd be careful with "Online UPS". Theoretically you are right that it should mean the same as double conversion. In practice this is not true. Some of the super cheap & rubbish ones are also marked "online".
Last edited:
I used a blazer or something like that..
700VA
The first time the power cut it kept my pc running for over 30minutes.. I only hooked up my pc with it and not my screen. But I see that these days it doesn't last longer than 15-20 minutes. I wonder why that is ._.
700VA
The first time the power cut it kept my pc running for over 30minutes.. I only hooked up my pc with it and not my screen. But I see that these days it doesn't last longer than 15-20 minutes. I wonder why that is ._.
UPS will claim surge protection in big letters on its box. Read its numeric specs. Protection numbers are near-zero. How does its hundreds of joules absorb surges that are hundreds of thousands of joules? It doesn't. How does that silly 2 cm part stop what three kilometers of sky could not? It does not. How does its power supply - typically inferior to what is required in electronics - somehow stop a surge that electronics could not? Read its numeric specs. It does not.
Anything that would work on a power cord is already inside the appliance. Your concern is a rare transient that can overwhelm existing superior internal protection.
Protection is always about where energy dissipates. Either a destructive surge is absorbed harmlessly outside the building. Or that energy goes hunting for earth ground destructively inside the building via appliances. Only you make that choice. Nothing stop the hunt once a surge is inside. Nothing - especially not near-zero protector circuits inside a plug-in UPS.
Surges are current mode events. That means voltage will increases as necessary to make the connection. Anything that tries to stop a surge simply sees voltage increase until the surge blows through that device. Surges find earth ground destructive via appliances. Or are earthed before entering a building.
Facilities that must never suffer damage use no plug-in protectors. Earth where every incoming wire enters the building. Coax TV cable connects directly to earth. Best protection means no protector - just a short (ie 'less than 3 meter') wire from cable to earth ground. Telephone and AC electric cannot connect directly. So a 'whole house' protector connects every wire in every cable to earth.
How many AC wires enter? Every one must connect to earth. One would already do so. All others must connect via a protector – to make the always required short (‘less than 3 meter) connection to single point earth ground.
Again, either that energy on every wire connects to earth. Or that energy is inside hunting for earth destructively via appliances.
Why does that UPS claim no protection in its numeric specifications? Where is the ‘less than 3 meter’ connection to single point earth ground? No earth ground means no effective protection. That UPS protection is invented in myths – does not exist in numbers.
A protector is only as effective as its earth ground. A ‘whole house’ protector also costs tens or 100 times less money per protected appliance. If you need protection for something, then you need protection for everything. Get the solution that is used anywhere that damage must not happen.
UPS is only for battery backup. Effective surge protection is always located where that energy can be harmlessly connected short to earth.
HavocXphere
Honorary Master
Good post westom.
UPS SELECTION HELP PAGES
its really difficult to select the correct size and type of UPS system. I have these links that will come in handy
http://www.phdpowerhouse.co.za/index_files/UPS systems help.html
http://www.phdpowerhouse.co.za/index_files/Calculations.htm
the company also has a monthly newsletter http://www.phdpowerhouse.co.za/index_files/LiveWire.htm
but really when selecting the correct UPS take your time and make the right choice, that goes for surge protection aswell
its really difficult to select the correct size and type of UPS system. I have these links that will come in handy
http://www.phdpowerhouse.co.za/index_files/UPS systems help.html
http://www.phdpowerhouse.co.za/index_files/Calculations.htm
the company also has a monthly newsletter http://www.phdpowerhouse.co.za/index_files/LiveWire.htm
but really when selecting the correct UPS take your time and make the right choice, that goes for surge protection aswell
go to this company they can help www.phdpowerhouse.co.za they also have indepth help pages
hey guys if you want to know how a 2 cm part can prevent surges here is a web page http://www.phdpowerhouse.co.za/index_files/PDF Specsheets/surge protection.pdf
Surges are absorbed by a MOV's and gas arrestors, these parts lie between live and Neutral, and Neutral and earth, if a surge comes down either one of the lines, lets say its the Live wire, and its greater the 275Vac then the MOV's and gas arrestors will operate and send the balance of the surge through to earth. MOV's come in verious KA ratings, the higer the KA rating the better the surge protection.
Lightning protection Class 1 equipment generally has a KA rating of around 200 and class 2 surge protection around 40KA
Surges are absorbed by a MOV's and gas arrestors, these parts lie between live and Neutral, and Neutral and earth, if a surge comes down either one of the lines, lets say its the Live wire, and its greater the 275Vac then the MOV's and gas arrestors will operate and send the balance of the surge through to earth. MOV's come in verious KA ratings, the higer the KA rating the better the surge protection.
Lightning protection Class 1 equipment generally has a KA rating of around 200 and class 2 surge protection around 40KA
How does a 2 cm part rated for hundreds of joules absorb surges that are hundreds of thousands of joules? It doesn't. But it must when a plug-in UPS has no earthing. UPS is only safety grounded. Earth ground is too far away, too many sharp wire bends, wire splices, etc. UPS has just enough (near-zero) joules to claim 100% surge protection to the naive. Numbers, especially in the manufacturer specification, make no effective protection claims. A UPS has only one purpose. Provide temporary (and 'dirty') power during a blackout.
No surge protector does protection. None. In every case, a protector is only as effective as its earth ground. To earth 200Ka or 40Ka surges, a wire to single point earth ground must be short (ie ‘less than 3 meters’) - low impedance.
Earth a ‘whole house’ protector at the service entrance so that energy is not inside the building. So that 20 Ka currents do not hunt for earth destructively via appliances. So that energy connects short (low impedance) to earth. Does not matter how many Kamps a protector is rated for. If a connection to earth ground is insufficient (ie too long), that energy must be absorbed (futilely) by the protector.
No protector (rated for hundreds of joules) will absorb destructive surges that are hundreds of thousands of joules. Always essential to a 40 Ka or 200 Ka protector is a low impedance connection to earth. Where energy must be dissipated. That means short (ie ‘less than 3 meters’). A protector without that short connection will be ineffective.
Temporary power and surge protection are two completely different problems solved by different equipment at different locations.
Dear Westom
Ageed, earthing is always essential, and the distance between the surge protector and your equipment even more so, that why surge protection device with the quickest firing rate is better.
When it come to UPS systems line interactive models let the current go straight through, where online units convert the DC from the rectifier and the batteries into AC through an Inverter, this conversion does ensure a clean supply onto your equipment with most of the incomming surges removed from your rectifier transformers.
i do agree that about 90% of surges can be removed from surge protection and filters in the DB board and only about 60 % of surge protection installed directly onto the equipment is effective (Due to distance) there is no fool proof way to 100% protect your installation expecially from lightning.
Ageed, earthing is always essential, and the distance between the surge protector and your equipment even more so, that why surge protection device with the quickest firing rate is better.
When it come to UPS systems line interactive models let the current go straight through, where online units convert the DC from the rectifier and the batteries into AC through an Inverter, this conversion does ensure a clean supply onto your equipment with most of the incomming surges removed from your rectifier transformers.
i do agree that about 90% of surges can be removed from surge protection and filters in the DB board and only about 60 % of surge protection installed directly onto the equipment is effective (Due to distance) there is no fool proof way to 100% protect your installation expecially from lightning.
spiderz
Honorary Master
UPS does not give you any real lightning protection. They only supply power to the pc when it goes out.
On a Online UPS you can hear then the hum of it converting the batteries to power. Unlike the cheep line interactive one's which only kicks in once the power are out.
he guys just check some people do a little bit of creative marketing some companies sell Inline UPS systems as online, this is a play on words and its actually a line interactive, we have found more recently that some companies just sell everything as Online, definitly check around before you by anything.
an online UPS shouldnt hum, the most you should hear is the fan.
check out this web page there is a great help section on UPS systems www.phdpowerhouse.co.za
an online UPS shouldnt hum, the most you should hear is the fan.
check out this web page there is a great help section on UPS systems www.phdpowerhouse.co.za
IEEE puts up better numbers when protectors are properly earthed. IEEE Green Book is entitled 'Static and Lightning Protection Grounding':
> Lightning cannot be prevented; it can only be intercepted or diverted to a path which will, if well designed
> and constructed, not result in damage. Even this means is not positive, providing only 99.5-99.9%
> protection. ...
> Still, a 99.5% protection level will reduce the incidence of direct strokes from one stroke per
> 30 years ... to one stroke per 6000 years ...
Well over 99% protection is why every facility that can never have damage spend mostly on the earthing - not on protectors, filter, etc. Protectors are only as effective as their earth ground. Plug in UPS has no such earthing. Is for temporary power. Is for data protection or user convenience; not for hardware protection.