Small UPSes
We reviewed four UPSes designed to be rack-mounted and to power up to four small pieces of equipment such as switches or routers.
APC PowerStack 450
The PowerStack 450 was the only 1RU UPS submitted for this review, and it is quite a nice unit given the limited space and the limited budget it falls within. This is a simple UPS with four female sockets and a serial port on the back. The display is limited to four individual LEDs for mains, battery, system overload, and replace battery.
The run time of just over 20 minutes was the shortest of all the units tested, but this is generally long enough to beat all but the worst of blackouts, and probably has room to grow. If this UPS was to be used in a network distribution cabinet, it would provide more than enough support for a number of devices, but the main shortcoming would be the lack of power outlets available. Hot swap batteries are a real bonus in this price range. The running cost score was an acceptable US$36.37 per minute, which is fairly good for a low entry price unit.
The PowerChute Plus software is very simple to use, and provides at a glance all the information you really need, while underneath is an excellent level of customisation that is well designed and laid out.
APC Smart-UPS 700
The Smart UPS 700 brings us into the “smart” level of the APC range, with various options including remote boot modules, network cards, environmental monitoring, and multiple serial ports. This 2RU unit also has nearly three times the battery life of the PowerStack 450 for less than twice the price.
The front panel display is much friendlier than the 450, with five-LED bar indicators for battery charge and load, as well as LEDs for trim (surge protection), boost (sag correction), online, overload, on battery, and replace battery.
The 700 shipped with an optional Network Management Card (AP9617 RRP $647) that allows network administrators to control the UPSes via various protocols like Telnet, HTTP, FTP, and SNMP. Using the Network Management Cards, you can monitor and configure the UPS to shut down and reboot your computer systems, send e-mail alerts, and view the event log. The Web interface was very easy to use, and the menus were clear and helpful. At 62 minutes, battery life was easily sufficient to handle a few switches and would happily cope with a couple of small servers or high-end routers as well. Running cost was close to the best at $16.76 per minute.
Sola UPS 520RM 750
The Sola 520RM is remarkable amongst the units tested in that it was the only UPS to have standard Australian 10A power sockets on the rear, rather than female IEC-320 10A sockets. This makes plugging units in very easy, as you already have all the cables you need, rather than searching out IEC-320 10A male-to-female cables. The front panel consists of an LED for AC in, which blinks when the UPS is bucking (reducing) or boosting (increasing) the input voltage. A second LED indicates whether the unit is operating on battery or not, and the remaining four LEDs indicate either the percentage battery charge or the percentage load on the unit. These LEDs also blink to alert you to alarm conditions.
The Sola 520 has a BestDock communications slot, which can accept an optional BestLink SNMP/Web adaptor (which was not supplied for testing).
The Sola UPS has a great expansion advantage; if you were to need more than the standard three power outlets, you could easily plug a power board into the UPS and run the devices from that. It is much more difficult to do that with an IEC-320 10A connector. Also on the rear of the unit is a network surge protector, which can be used to protect your equipment from a surge via your Ethernet cable. This is often used where Ethernet is run from another building, or another part of a building, and might be subject to a surge (eg, a lightning strike).
The CheckUPS II software supplied with the 520 does a good job of controlling the UPS, and has a very informative display, but it is missing a percentage charge indicator, which makes it difficult for us to tell when the batteries are fully charged. The tested battery life was an acceptable 50+ minutes, which means there is plenty of room for expansion. This also gave it the best running cost score of just $15.55 per minute.
Upsonic Pro Power PLUS 700
The Upsonic Pro Power plus 700 has a simple front panel layout, consisting of a combined bar-style load and battery level indicator, and additional LEDs for fault, bypass, battery, inverter, and line input. To switch between load level (the default display) and battery level, you need to press the on/off button for one second to put the unit into test mode. The only problem with this is that pushing the button for two seconds will turn the unit off completely, which is asking for trouble.
There is a SNMP slot in the rear of the unit, but it is only briefly mentioned in the very generic manual. When we removed the cover, there seemed to be nothing to plug a card into. Upsonic sent us an external Net Agent II network adaptor, which we were able to connect up to the UPS and plug into our test network. This device allowed us to set a range of notifications, but it was rather difficult to use and quite confusing to install.
On the rear of the unit there are 4 x 10A sockets, though we did have a problem with two of them—the contacts didn’t quite meet correctly, and sometimes, with some plugs, we had to wiggle the cable a little to get a proper connection.
There is an external battery connector for adding an extra runtime and phone protection socket, which seems a little odd in a unit that is going to be in a rack, though you might use it to protect a dial-in line.
Battery life on the 700 was the best of all the units tested, keeping the three switches running for over an hour and seven minutes, but the high purchase price means this unit has a running cost of $25.89 per minute in our tests.
The Upsilion 2000 Software that came with the unit was excellent. A small daemon runs in the system tray and when the application starts up, it connects through this to the UPS. There is a large range of display options and an even larger array of configuration options in terms of notification of problems and shutdowns.
