The UPS and downs of power supply

The UPS and downs of power supply

The lights flicker. Then, almost as one, the sorrowful cries erupt from every cubicle . . . "Oh no, I've lost my files". A single, sub-second power surge has just wiped out a day's worth of work in the office. And, of course, that proposal is due in a few hours . . . Phil Parent investigates the latest developments in UPS.

The above scenario is indeed a painful one and, to be sure, one that most of us have had to endure on occasion (those in Auckland on a very long occasion). But it's one that can be easily avoided with a relatively low-cost and technically straightforward program of power supply management.

Power supply management can consist of a number of different components: surge protectors, filters, conditioners, voltage regulators, uninterruptible power supplies (UPS) and the power management software that monitors the various components.

The need for a power supply management solution has never been greater. "Power conditions are getting worse," says Murray Irwin, international sales manager for International Power Technology. "Added to that is the fact that the systems we are running are becoming more sensitive to power fluctuations and require ever cleaner input, and the power requirements for components are increasing. For example, a 17 inch monitor takes maybe 20 per cent more juice than a 15 inch monitor, which can reduce the battery back-up time by a crucial five minutes or so in a power outage. And, of course, more mission-critical functions are being supported by IT. We only have to look at last year's Auckland power crisis to see how dependent we are on electricity for our livelihoods."

Implementing a power supply management solution is not rocket science. "Installing a basic UPS is as simple as plugging it into the computer," says Chris Gemmel, director of MasTec International and one of New Zealand's leading power management specialists.

"What we focus on, however, is future-proofing the installation to ensure that as the infrastructure grows, the power protection can grow in tandem. An under-protected site is almost worse than a site with no protection as it leads to a false sense of complacency."

Critical devices

Working out the requirements for a company is a straightforward process. "We look at all the critical devices to get a feel for the total power requirements and work back from there," says Gemmel. "We ask the client to prioritise the systems. We are adamant about the development of a disaster recovery plan. It's a written outline of what systems need what input as well as their shutdown requirements. A written plan also helps us when it's time to upgrade."

When most people think of power supply management they think of a UPS, but there are other options as well. Surge protectors, filters and voltage regulators all have their places.

"Power, even if it is generated cleanly, can become corrupted by many sources," says Denis O'Callahan, Eagle Technology's resident UPS guru and veteran electrical engineer.

"A lightning strike, an electric motor starting up, or even powering up a computer can affect the incoming voltage causing what we call 'transient voltage', or a spike. Electricity consists of sine waves in a regular pattern and these spikes are in essence pattern fluctuations. A surge protector is designed to kick in when the voltage passes a certain threshold, protecting the device. Most PCs have built-in surge protectors, but external protectors can add more reliability.

"A filter, on the other hand, is better suited to cleaning up bad power," says O'Callahan.

"Spikes are typically very short in duration but chronically bad power can cause all sorts of problems. A low-pass filter removes the sine wave variations by attenuation and reconfigures the power to a pre-defined pattern. The noise is removed and we can get on with the job."

"Voltage regulators are also handy, but they are gradually being replaced by all-inclusive UPS solutions. Regulators also even out the signal and are best used in brownout situations. A good power supply management program might incorporate all of these components tied together by a power management software program."

If all of this reminds you of image processing it is no coincidence. The latest developments deal with pattern recognition and digital signals. "Our new UPS systems incorporate digital power conditioning," says Irwin. "Instead of using a switch or a transformer, we use a signal processor to take the incoming wave and regenerate it to match a pre-defined pattern.

"Not only does this provide a much more even flow of electricity, it cuts down on the componentry required. We expect to see more of this in the future."

Power supply management protects the entire network, including computers, routers, hubs and other attached electronic equipment. Interoperability is a key requirement for any device that connects to a network. While network-wide power protection can be represented in a simple shutdown interface, today's increasingly complex networks have a real need for built-in network communications to ensure reliability and compatibility among all the various devices connecting to it. The standard communications protocol UPS vendors are using is called simple network management protocol (SNMP).

Because this standard defines how UPSs and other devices communicate over all networks, SNMP capability, in turn, enables UPSs to do more than ever before - and to do it more "intelli- gently". UPSs with SNMP communications, for example, can log events, continu-ously monitor power quality, report on battery status, load and temperature, and perform self-management diagnoses.

The most popular component of a power supply management program is the UPS. In short, a UPS is an emergency power supply that gives users enough time to power down a computer or network in the event of a power outage. In addition, most UPSs contain the above-mentioned surge protectors and filters that even out the flow of current to those systems. In addition to the UPS unit itself, all but the most basic UPS packages are bundled with power control software that performs a variety of management functions. Among the most popular types of UPS devices are the online, stand-by and line-interactive protection systems.

Online protection provides the highest levels of network protection and conditioning. In an online UPS, the inverter - a device that converts DC to AC - supplies conditioned power to attached devices all of the time. Most online UPSs supply five to 10 minutes of battery backup, which is more than enough for 98 per cent of all blackouts, as studies show these situations typically last no longer than two minutes.

For the other 2 per cent of blackouts, online UPSs are available with extended battery capabilities. Online technology is often the best choice to protect critical applications - those that simply cannot be "down".

Offline, also called stand-by, is a cost-effective choice for small, non-critical stand-alone applications, for example, isolated PCs and peripherals. While these computers can be connected to a network, communications is usually not a necessary component and a stand-by provides sufficient back-up.

This type of UPS typically powers the load from the utility input when available, but switches to the inverter (supplied by the battery) when the utility fails. Stand-by UPSs include a battery charger to maintain the charge.

For highly effective power conditioning and UPS backup, there is line-interactive technology. Line interactive technology is particularly applicable in areas where power outages are rare, but where there are frequent power fluctuations. For example, power-hungry equipment in most industrial applications gets switched on and off frequently, causing voltage fluctuations that, while not as damaging as a complete loss of power, can still result in destroyed data or system-wide corruptions. Network communications are available in line-interactive UPSs.

Once the system is in place it has to be maintained. "Keeping your UPS in A-1 condition is a constant process," says Gemmel. "IT managers should be testing them on a regular basis to ensure that the batteries are charged, that the software is operating and that the required loads are still in sync. Too often people will install a UPS and then upgrade the system and not upgrade the UPS." Business is booming in the UPS market. Many of the hardware maintenance contracts now specify that a UPS should be used, especially with NT platforms as they take so much time to power down - an exchange server can take up to 40 minutes to shut off.

"Last year we sold out our entire stock in a week," recalls Gemmel. "This year our business is up about 60 per cent. But my most vivid recollection of last summer is having to carry these bulky and heavy UPS units up 10 flights of steps in hot humid weather in pitch blackness to a client's site. By the time I got to the top I was a real 'user abuser'."

"There are two kinds of UPS buyers," says Irwin. "Those who have been stung in the past and those who will be hit in the future and want to protect themselves."

Solid Clary DT1000 performs well online

by Mike Avery

As a network manager, I look for three major elements in an uninterruptible power supply designed for an enterprise networking environment. First, the UPS should deliver solid, stable power; second, it should be easy to use and configure; and third, it should be able to signal the devices it is powering to warn them of imminent power failures. The Clary DT1000 from Clary performed the first set of operations well; unfortunately, the difficult-to-use USHA card included with the product caused some problems.

According to company officials, the card I tested was a beta version. Nevertheless, at this time I can only recommend the unit for stand-alone devices for which monitoring and control are not essential.

The Clary DT1000 is an interesting device for several reasons. Unlike most UPSs on the market today, the Clary DT1000 is an online UPS rather than a switching UPS. Whereas a switched UPS switches to battery use when the line power fails, an online UPS is always using its battery. Thus, when the line power fails, there is no changeover and no chance of a spike or glitch.

The Clary DT1000's SNMP and Web interfaces worked well; for example, I could get information on the internal state of the UPS to see the load and battery condition. Also, graphs could be changed from showing present status to showing the device history with just a mouse click, and it was easy to put all the history graphs on a single screen at once.

The Clary DT1000 can maintain a lengthy history, which lets managers see what has happened during the past week, month, or longer period of time. The only problem I encountered here was that the UPS' temperature gauge measured in centigrade, which will likely annoy many system managers.

Other devices

What also sets the Clary DT1000 apart from other UPSs I've seen is its capability to use the USHA Smart Adapter to control other devices via TCP/IP and to monitor the UPS via SNMP or a Web browser. When you have a large UPS that can power a number of devices, determining how to shut those devices down when the UPS loses power can be tough. Using the LAN connection already in place, which the Clary DT1000 does, is a very attractive solution.

However, the provided USHA card could not use Dynamic Host Configuration Protocol or BootP to get its IP address, so its initial configuration had to be done via the serial interface. This wasn't helped by the contradictory band rate information offered in different parts of the manual, or by the fact that it was unclear which of the cables or adapters should be used to connect the UPS to a PC or terminal. It took me approximately half of one day to get my laptop and the UPS communicating with each other, though Clary's technical support staff was helpful during this process.

The USHA card did let me shut down a PC when the UPS lost wall power, but I ran into problems when testing the shutdown function. For example, the Windows 95 PC I was using refused to shut down entirely. Also, once the shutdown was triggered, there was no way to stop it. When power was restored to the UPS, the PC still tried to shut down.

Clary's technical staff eventually found an upgrade for the UPS to fix it. But despite spending a good amount of time on the phone with technical support, I was not able to apply the upgrade. The USHA card I was given, which was causing these problems, had never been tested directly by the company but was being offered through a subcontractor, according to Clary officials.

This left me feeling uncomfortable with the product.

In short, the Clary DT1000 hardware worked fine, and for managers who prefer online UPSs it is a good choice. But problems with the product manuals and the shutdown software make it hard for me to recommend the product to most enterprise system managers.

There is no known Australian distributor for this company at present.http://www.clary.comWhat's new from . . . Chloride Power ElectronicsAladin - Uninterruptible Power Supply 250VA to 600VATypical usageProtection of personal computers, modems and other electronic equipmentHighlightsSet and forget - automatic power on and off control Audible status indication for under-desk placement Battery back-up provides approximately 20 minutes of computing time during a power failureIt ensures that modem is online when needed in the case of power outageChloride's UPS Aladin range is designed to prevent data loss due to power variations. It also prevents read/ write errors from occurring. As one of the most user-friendly UPSs on the market, Aladin boasts completely automated operation. The unit needs simply to be plugged in, providing immediate protection. All products in the range feature audible status indication, keeping users informed about its status and when the electrical power is bad. Depending on the processing power of a PC, Aladin offers between 10 and 15 minutes of battery backup time.


Aladin 250VA for 386 PC and monitor. Backup time typically 15minutesAladin 300VA for 486 PC and monitor. Backup time typically 12minutesAladin 400VA for 486 multimedia and monitor. Backup time typically 12minutesAladin 450VA for Pentium, modem and monitor. Backup time typically 10minutesAladin 600VA for Pentium multimedia and monitor. Backup time typically 12minutesChloride Power ElectronicsTel 1800 252 824What's new from . . . American Power ConversionAPC BACK-UPS PRO 280kVA, 420kVA and 650kVATypical usageProtection of applications, peripherals and data in small-to-medium enterprises (SMEs)HighlightsUnattended file-saving software integrated with Windows 98Additional battery outlets One-line phone/fax/modem surge suppression Automatic voltage regulationUser replaceable batteries Push-button/resettable overload protectionAudible battery alarmsThe whole Back-UPS Pro range has been designed to ensure continuous systems availability for high performance PCs. All products feature file-saving software that integrate with the Windows 98 power management application to automatically save files and shut down the PC in the event of a power outage.

The Back-UPSs range also protects voice and data telephone lines used to access the Internet or company LANs, conditions raw utility power coming into a PC and offers three battery back-up and one surge-only outlet for multi-path protection of peripherals.

Prices start at $350 for APC Back-UPS Pro280.


Typical usage

Protection of multiple servers, mainframes and business-critical applicationsHighlightsDelta conversion technologyDP300E controller software DP-SOFT CDXCommunication facilities with multilingual informative interfaceCompact designBuilt-in cooling fan monitor All Silicon products feature internal "powerfactor" correction technology that eliminates the need for an external phase compensation unit and allows the use of smaller cables and fuses. Silicon's delta conversion technology also allows installation of less-expensive back-up diesel generators. The range maintains an original sinusoidal main current and allows up to nine DP300E systems to be installed in parallel.

APC PowerStack 250VA and 450VA

Typical usage

Protects hubs, switches, routers and remote access internetworking equipment from power disturbances.


User-replaceable, swappable batteries

Smart signaling capabilities

Correction of over and under voltages

1U of rack space

Desktop or wall mounting capability

The PowerStack range was designed to help increase network availability and reduce downtime in a mission-critical internetworking environment. Boasting smart signalling capabilities, APC PowerStack enables both remote and on-site users to manage network power, while its voltage correction technology prevents the draining of battery power increasing UPS' disaster-readiness.

Prices start at $790 for PowerStack 250VA.

American Power Conversion

Tel (02) 9955 9366

What's new from . . . Nikko


Typical usage

Internet/intranet computers and advanced serversHighlightsSpike and noise suppressionSag and surge protectionTelephone/modem surge suppression portsFree power management software for safe server shutdownTwo-year warranty including batteriesY2K compliantFeaturing digitally restructured sine wave output, Nikko King Pro UPS comes in five models: 425VA to 2000VA. All models include an Internet connection for surge suppression of telephone lines that enables computer monitor and modem to be protected on both the power and telephone lines. The King Pro UPSs are microprocessor controlled and are plug-and-play interconnective. With 10 minutes of nominal backup time, all models also have advanced input filtering and spike suppression and come with hot swappable batteries, battery replacement indicator, RS232 interface and SNMP facility. Reseller prices start at $190.00.


Typical usage

Advanced servers, coms and PABX


Spike and noise suppression

Sag and surge protection

Free power management software for safe server shutdownTwo-year warranty including batteries and extended warranty optionY2K compliantThe Nikko Smart King UPS is available in 5 models (600VA to 3000VA). Featuring pure sine wave output, the Smart King UPSs include plug-and-play interconnectivity, extended battery options for long backup time and remote monitoring for unattended sites. They are microprocessor controlled and have a 10-level graphics array and SNMP smart slot, advanced input filtering and spike suppression. Also included are battery replacement indicator, battery life extender program, RS232 interface and a bundled UPS Power Management Software Package and 10 minutes backup time capability on all models.

Reseller prices start at $490.00.


Typical usage

Advanced servers, coms and PABX


Online double conversion technology

Integral bypass

Free power management software for safe server shutdownTwo year warranty including batteries + extended warranty optionsY2K compliantAll five Nikko online DataPower UPSs are available in stand-alone or 19 inch mount configurations.

DataPower UPSs provide galvanic isolation that enable the output to be completely shielded from input spikes and noise. All models have inbuilt automatic bypass, digitally controlled inverter, minimal distortion feedback into the mains, RS 232 interface, SNMP capability and bundles CD-SOFT CDX UPS Power Management Software package.

Reseller prices start at $995.00.


Tel (02) 9907 0922

What's new from . . . Sola

SOLA 305 UPS 250VA, 425VA and 600 VA

Typical usage

Protection of personal computers, workstations, computer peripherals, point-of-sale equipmentHighlightsBuilt-in intelligenceSurge suppression Audible power disturbances alarmsInternet protectionCold-start and shut-down capabilitesTwo-year warrantyThe Sola 305 products protect PCs, computer peripherals and SOHO applications against spikes, surges, sags, noise, lightning and blackouts.

The range comes with uninterruptible power/surge suppression and two surge suppression outlets, spaced for plug pack use.

Sola 305s feature Internet-ready telephone line/modem surge protection, as well as optional CheckUPS II Suite power management control software and connecting cable.

Its battery technology management assures optimum runtime, both on failure and recharge, with auto restart included.

SOLA 320 UPS 400VA to 1000VA

Typical usage

Protection of network workstations, UNIX workstations, CAD/CAM/CAE workstations, departmental servers, desktop servers and PCsHighlightsBuck/boost indicatorHot-swappable and user-replaceable batteriesIntranet readyWin 95 Plug & PlayCheckUPS II software bundledTwo year warrantyThe Sola 320 UPSs offer protection from spikes, sags, surges, noise and lightning,. Featuring intranet-ready 10BaseT network protection, RS232 serial communications and advance battery management technology, Sola's 320 range was specifically designed for Australian applications and offers multiple Australian sockets and meets all Australian safety standards.

SOLA 520 UPS 750VA to 2.25kVA

Typical usage

Pure Sine-wave power protection for network computersHighlightsHigh mean Time Between FailureBestDock communications slotNetwork transient voltage surge suppressionUser programmable voltage switch pointsUser-replaceable and hot-swappable batteriesCheckUPS II Suite power monitoring and shutdown softwareSola's 520 uninterruptible power systems offer protection against spikes, sags, surges, noise and lightning and are suited for sensitive and mission-critical equipment that requires pure and continuous power supply. Its built in self diagnostic routines enable power related data corruption or loss. The SOLA 520 range also enables users to customise the power of advanced voltage regulation to their specific applications and to add connectivity options, such as the Internet connection.


Tel (02) 9949 6000

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