Uninterruptible Power Supplies
UPS units serve multiple purposes, and they come in different form factors.
Enterprise-class devices are usually created for 19” rackmount environments; this is the case for the device we reviewed. However, there are many pedestal units available as well, which can be positioned right next to the systems they are intended to support.
All UPS unit share (or at least should share) a common characteristic, which is substantial weight as a result of the batteries used to provide backup power. Although there are much more capable battery solutions, lead-acid batteries are still most commonly used because they are affordable, reliable, and pretty predictable. In addition to lithium-ion technology, they are safe, as they cannot catch fire.
UPS Features
An uninterruptible power supply is meant to maintain power in case of a power outage. Depending on the battery capacities and load, different UPS devices can bridge a certain amount of load for a particular amount of time. Some UPSes are designed to provide just enough power for a short power outage, to allow administrators or the UPS software itself to shut down systems safely. Others are designed to bridge a longer period of time, although you’ll have to get a diesel generator or similar to be able to run servers truly independently from the power grid. Almost all UPS units come with surge suppressors to protect attached devices, and most also come with hardware to filter the electric current in an effort to maximize the power “quality.”
UPS Interfaces
Devices typically have one power input and several outputs. The input has to be connected to the power grid, while the outputs can be used to connect client devices. Some outputs provide only surge suppression and filtering, while those providing backup power may also be divided into different segments for different buffering scenarios. The Powerware PW5130 unit even has a C19 output, which is good for up to 16 A, while the other C13 outputs (three pin power connectors) serve up to 10 A. Some UPS units also have ports to protect network paths from surges, but this isn’t the case for our review unit.
UPS Types
Professional UPS devices may use a rectifier (double conversion online UPS) or a transformer (delta conversion) in front of the battery, but this applies to enterprise-grade UPS devices, which we aren’t interested in at this point. The two most popular types are standby UPS units, which remain in standby mode and only switch to the battery if main power fails, and line-interactive designs. The latter is based on having the AC/DC inverter as part of the active circuit at all times.
Battery Backup Basics
Once you know the functional details and features, you’ll have to pick a UPS unit that will be powerful enough for your type of application. The first step is the power rating, which is typically specified in VA (volt-amps). It is important to know that these ratings consist of effective power and reactive power, hence the number does not reflect the actual maximum power the UPS device can supply. You have to look into the product’s data sheet to find out the difference. In the case of the Eaton/Powerware unit, this is 2,700 W based on a 3,000 VA total power rating. The data sheet will then tell you how long the battery will run based on a certain load.
Whats up with the recap first comment these days? Google archive?
so annoying, right? I agree ^^^^
Btw, is this simulated sine or true sine?
Whats up with the recap first comment these days? Google archive?
I guess Tom want's to get first post credit for everything.
Simulated. The 5130 is a line interactive unit, and as such uses an approximate sine wave - most likely stepped (I don't know for sure though). You need to step up to the online/dual conversion units to get the true sine wave power.
Also, I, too, am annoyed at the recap comment
FINALLY > if any one ever has questions about UPS's, let me know. It's my job.
etrnl_frost,
Since you ask, How bad is stepped sine waves for a computer system(So far, it has not hurt anything, 3 computers, router, screen, speakers, phone base, cfl light[this does restart{flash like its just been turned on} during a power out])?
Good article....
Every small business should have at least one of these.
Simulated. The 5130 is a line interactive unit, and as such uses an approximate sine wave - most likely stepped (I don't know for sure though). You need to step up to the online/dual conversion units to get the true sine wave power. Also, I, too, am annoyed at the recap comment FINALLY > if any one ever has questions about UPS's, let me know. It's my job.
This is a pure sine wave unit, and that has nothing to do with being line interactive. This is your job?!
Exactly. Being a line interactive doesn't determine if the UPS uses a True Sinewave. APC in one of their three SMART series has line interactive with true sine.
Am I missing something special about this unit? How is it any different than APC, Tripplite, Minuteman 3000VA UPS models?
Nukemaster:
Feel more than free to correct me as both you did earlier - it gives me reason to learn more about what I've been doing (only a year)....
It's really not that important, all things considered. PSU's nowadays can handle a stepped sine wave quite fine. However, certain things like VoIP switches can experience QoS issues with an approximated output.
pdjh1960, mutantmagnet:
Let me clarify - my job is specifically TrippLite technologies. I'm not as familiar with Eaton technologies, and had to look up this unit. The site I chose said it was a line interactive unit. I checked again today, saw somewhere that said it was an online... etc. So, I did some learning of myself, and found that Eaton's nomenclature is as follows - 3-series are standby, 5-series (this one) are line-interactive, and 9-series are on-line. Here's the catch; you're partially right.
mutantmagnet:
APC "claims" to have true sinewave with their line-interactive... However, as far as I know this is a conditional technicality (unless they came out with something recently that I don't know about).
Essentially, the On-line units, by way of always running off their battery, are consistently outputting a preprogrammed sine wave. A line interactive unit can do a true sine wave from battery. By it's definition though, it's using an auto-voltage regulator to smooth out the input power when it's bypassing direct from utility. Auto voltage regulation is not exact (again, unless someone invented something I don't know about), and you will inevitably have harmonic distortion. Thus, you do not have a perfect sine wave. In other words, yeah you can get pure sine wave power, but only when the power's out. Otherwise, it's bypassing corrected utility power, which - unless someone can provide me a white paper - as far as I know it's not going to be as "nice" as an online unit's output.
ralltir:
Really, in the end, until you are starting to look at anything above 5000VA, the units are pretty much the same. There are some lines that claim to be different (I know Tripp Lite claims to have the only hot-swappable line-interactive rackmountable 3000VA unit, but I believe APC has an equivalent, for example), but these are major exceptions to the rule (with regards to what I typically see leave a major reseller's doors).
Final clarification: As stated before, I'm a TL rep. However, I'm not paid by TL, and my job is provided for the aforementioned major reseller. As such, I am immune to kool-aid.
> In addition to lithium-ion technology, they are safe, as they cannot catch fire.
Lead acid batteries can and do burn. They are substantially resistant to thermal runnaway, and they are compared to lithium ion more stable, but there are limitations.
Furthermore it is worth noting that it is possible to damage gel cells by discharging them to quickly, discharging them completely or allowing them to run excessively hot.
joelja: After reading some of the stuff Eaton's posted about this model on their website, I am questioning some of the bullet points they list... I'm assuming that's where you got that bit about the battery tech?
Why even bother with all this nonsense? Real hardware gurus go straight for the 48VDC ATX power supplies and a string of 4 12v batteries with a high amperage inverter. Duh.
Why even bother with all this nonsense? Real hardware gurus go straight for the 48VDC ATX power supplies and a string of 4 12v batteries with a high amperage inverter. Duh.
Heh, like google did for their servers? Maybe not the same string of batteries, but...
If only there were more hardware gurus out there, yah.
The 51xx series is Powerware's (formerly Exide Electronics, which aquired Deltec/Fiskars), it has nothing to do with MGE.
The segmentation of outputs and LanSafe/FailSafe III are from Deltec's design and software legacy (UPScode II protocol).
Powerware also acquired Best Power/Sola, and killed most of their product line.
Short history:
Deltec was purchased by Fiskars (FPS - Helsinki)
FPS was purchased by Exide
Exide was purchased by BTR (London) and the product line was re-named to "Powerware"
BTR then merged with Seibe (London) to become "Invensys"
Interesting tidbit, there, ossie. I sit right next to the Eaton specialist where I work... and it surprises me how often he's yelling in frustration because of the many different kinds of outsourcing that is done by Powerware. One of those things where everything comes from everyone, so it's hard sometimes for him to determine who to go to, because it all seems unrelated
Eaton is probably just another step... As management/shareholders are more interested in the money, since Exide days, rather than in the product, the usual pattern of buying/selling will continue.
Deltec had one marvelous product line, both electronically and management SW wise (when APC still struggled to define their UPS product line) - at least the current line of Eaton low power UPS products, based mostly on it, managed to keep most of their qualities.
Schneider bought Merlin Gerin (late '80s) and APC, a few years ago, but kept just the high power end of MGE (EU antitrust), the low power one ended at Eaton, and will probably be mostly discarded, as usual.
Lets hope Eaton will keep Exide/Powerware's policies of, at least, offering technical information and SW for former product lines of the companies they bought, even without active support.
Also, MGE had a tradition of supporting FOSS, unlike APC.
I guess the Schneider rep is even more frustrated...
@joelja "They are substantially resistant to thermal runnaway"
Actually they are not, and have a quite large negative thermal coefficient (~ -3.9mV/C/cell), which, when neglected, can lead to shortened life, or even failure. Also, high and low temperatures have a detrimental effect on life time.
APC was quite infamous for not using thermal compensation in their Smart interactive series, leading to premature battery failure - don't know if they fixed it in newer units, but they have a business in selling replacement packs...
@joebob2000 -48V DC bus is established in the telecom industry, but is inefficient for high power systems, implying a lot more copper at the same power levels, than higher voltage AC (the old Edison/Tesla currents war). Most UPSs over 1000VA use internally 96V or even 192V DC, for higher efficiency.
Also, to charge the batteries you need a rectifier, not inverter.
As the transition from circuit-switched to packet-switched networks advances, this legacy of early telecom days will probably fade away.
As a footnote, the THG dynamic duo should be kept away from all electrical energy matters, they still don't grasp it.
"In addition to lithium-ion technology, they are safe, as they cannot catch fire."
H2-02 gas mix in a closed recipient is not exactly "safe"...
"The 3,000 VA unit provides a 12V, 9 Ah battery unit."
That would be rather 6 12V units (or a 72V one).
A worrying trend is emerging, newer units feature just limited internal capacity (~3 min at full load), leading to almost mandatory purchase of at least one EBM.
"The PW5130 is a true behemoth, weighing in at 34 kg"
It could be considered quite light, the Compaq R3000 (PW5119) clocked at 60kg, but it had a lot more storage capacity and was extremely sturdy. Still have a few ones working after a decade...
"LanSafe seems to be the original Powerware product, while the PW5130 is based on MGE OPS technology."
oops, actually both are... (cleared that up in the previous comment)
Line Interactive, which APC made popular (although they make Double Conversion Online and Delta Conversion units as well now), is perfectly fine for IT equipment, which largely uses switching power supplies that are perfectly capable of handling the extremely short switchover moment when the unit goes to battery.
Powerware UPS hardware isn't too bad but every Tripp Lite I've ever bought has died after only a year, I expect a UPS to last at least a few years.
Powerware's software is a little on the cheesy side though, it's no PowerChute.
ossie: I hear you on the bit about decreasing run times on internal systems. It's truthfully getting harder and harder for me to find systems that can meet the customer req's with the internal batteries, without going to some ridiculously low load percentage. I know APC's got some "extended runtime" UPS's that have some better runtimes on the core units.
Edward5731: One year? That should still fall under the 2 year standard warranty (unless you're getting the cheapy units). Which ones did you use, and under what kind of settings (what were you running), may I ask? I always try to take notes on these sorts of things. Customer testimonial, good or bad, is always useful.