PERSPECTIVES - They've got the POWER

The UPS has changed dramatically, both in terms of looks and increased reliability. VNU Labs put eight power protectors to the test.

For all intents and purposes, the core technology of every UPS iseased reliability. VNU Labs put eight power protectors to the test. just a big battery, which provides energy for computers when the mains power fails. But today, this is only the start, as the latest generation of UPSs does a whole lot more.

Every computer that is plugged into the mains is subject to surges of power, since no mains supply is ever 100 per cent pure. Blackouts (total power outage) and brown-outs (periods of low supply) are one thing, but spikes (momentary increases) and surges (periodic increases) are far more dangerous. Spikes and surges can reduce the expected lifetime of hardware and even cause a machine to crash, resulting in a loss of data.

This is another function of a UPS - stepping in and cleaning the power before it reaches the computer, by ensuring that the power stays between a certain maximum and minimum level.

However, for the purpose of this benchtest, VNU Labs excluded the possible adverse effects that depend on how clean the power from each UPS is. This technology has been around for a long time and the testers were confident that all of the machines on offer would cope with this function correctly.

Keeping the lights on

The point of a UPS is to keep servers up and running for a longer period of time when the power fails. However, if no one is there to deal with it, eventually the server will crash as the battery runs dry, with a possible loss of information.

Part of the software provided with the machines is a client that sits on the server. This communicates with the attached UPS - either via a serial cable or by using the network - and should mains power fail, the UPS broadcasts a message informing the client.

The client program can then be set up to shut down the server after a given period of time. This means that should power fail when there is no one around, the server is still correctly shut down. The client software can often be instructed to inform users of the problem, either through standard messaging, email or even paging an administrator.

In addition, these clients can often look out for other events, such as losing the connection to their UPS. This information can help identify and solve problems before they become too serious.

Management is also an important issue and it has greatly improved over time. UPSs were traditionally managed using a serial port on the back of the unit, but this raised the problem that it was only possible to manage the device from the attached machine. Most of the models provided for this test now include network cards, enabling the UPS to be managed from across a network.

The most common form of this is through SNMP, using a popular management package such as HP Openview. This makes it much easier for an administrator to manage the network, as it can be done from one central location.

One area that is likely to become significantly more important is Web-enabled management. This is even easier than SNMP, merely involving pointing a Web browser at the IP address of the UPS.

Test results

Most packages provide tests that can be run on the UPS to check, for example, battery power. These tests can often be scheduled to run at defined intervals to save the administrator having to do that job. Other areas - such as current battery power - are important, as the administrator can then make sure that the battery is charging.

Using these criteria, VNU Labs tested eight UPSs from a selection of leading manufacturers.

APC SmartUPS 2200

APC is a well-known company in the UPS field, with a reputation for quality. Its SmartUPS 2200 is no exception, with eight receptacles on the rear capable of outputting 2,200Va.

The array of LEDs on the front informs the user of the current battery charge and will also indicate if the UPS is having to compensate for either high or low power.

APC provided a network card with this UPS, which plugs into a slot at the rear. This slot can also be used to house a range of other cards, including one that will measure the temperature and humidity of the room it is located in.

The network card that was provided needs to be configured through the serial port. APC has made this job a lot easier by including a piece of software which is basically a wizard. This asks the reseller about the configuration required and writes the information through the serial port to the network card. This makes configuration a whole lot easier. Alternatively, a terminal package can be used to do the job manually if preferred.

Once the card has been configured, it can either be managed via SNMP or, better still, a Web browser. The browser option is by far the easiest to use and set up and gives an administrator the opportunity to perform management tasks from anywhere on the network, even across the internet.

The amount of information that can be gleaned from the SmartUPS 2200 is huge. Information on the current battery status, the temperature of the unit and items such as runtime remaining can be viewed.

The main piece of software is called PowerChute. This enables a computer to be safely shut down either over the network or through the serial cable.

PowerChute also has installation options for shutting down applications such as the Back Office suite, plus a list of other software. This is a well thought out option, which ensures that as little damage as possible is done in the event of a power failure.

APC provides some of the best software there is and combined with the quality of the unit, corporates can't really go wrong recommending this unit to a client.

Best Power Fortress 2250

The line-interactive Fortress 2250 has four receptacles, supporting a power output of 2,250Va. The LEDs located on the front of the device indicate the current status of the UPS by informing the user of faults and giving a readout of current battery power. The unit contains an expansion port on the rear, made to take one card.

Best Power provides an SNMP/Web adaptor using a unique and clever method. The adaptor is a small box that plugs into the network via a standard RJ-45 cable. The box also has two extra ports that connect to a PC's serial port and to the RS232 port on the UPS. This method means that the Web adaptor will work on any Best Power UPS, without the need for an expansion slot.

Initial configuration can be achieved through either a terminal package or by using a Web browser. The browser setup works well because Best Power ships its SNMP/Web adapters with a default IP address.

Once the adaptor has been given an IP address, it can be managed via a Web browser. This option allows current information on the UPS, such as runtime remaining and input/output power, to be viewed. If it is necessary, the UPS can perform tests to make sure that it is operating correctly.

The only options that can't be reached through the Web interface are the security options. Should the user want to manage the UPS with SNMP, this can be done using a package such as HP Openview.

The Web browser option is once again the easiest way to manage the device.

It requires very little effort to start and gives the advantage of being able to manage it from anywhere.

Software was also provided to enable the server to be shut down properly.

Its options can be accessed via an icon in the Windows NT control panel on a PC. This enables the shutdown time to be set, based on the amount of UPS battery power remaining, as well as sending messages. But, ultimately, there are very few options here.

The Fortress 2250 is very easy to get up and running and standard management functions are even easier to perform, especially using the Web interface.

The shutdown software, however, is very basic.

Chloride Baby Synthesis

The online Baby Synthesis is a huge unit - easily as big as a full tower machine. With a power output rating of 5KVa, it is capable of supporting the most power-hungry of peripherals.

These are connected to the UPS via a standard two-gang adaptor, which plugs into the rear of the unit. This gives the advantage that all kinds of peripherals can be plugged into the UPS without the need for a converter of any kind.

The front of the unit holds three LEDs that inform the user of the current operational status. Should more information be needed from the UPS itself, a liquid crystal display can be fitted instead. As well as containing the LEDs, this display shows plain text messages and allows access to a number of operating parameters.

In order to look at the software provided, the Labs used the RS232 management port. However, it is possible to use a network card to allow the UPS to be managed via SNMP. The software serves the job of both allowing the user to monitor the UPS and shut down a computer in the event of a complete power failure. The monitoring software features a series of charts displaying the current status of the UPS. To this end, there are charts showing current battery power, temperature and the amount of autonomy time currently remaining.

Each of the charts is colour coded, so, for example, if you see a green chart, you know that particular area is functioning correctly.

The monitoring software also stores a list of the latest events, allowing the user to see if a problem has occurred in their absence. Chloride provides UPSMan to automatically shut down a machine in the event of a power failure.

This is the same piece of software used by Gresham and does the basic job. By installing itself as a service, it can be configured through the Windows NT control panel. Options such as deciding which three jobs to execute in the event of power failure and which files to write the logs to, can be chosen.

The Chloride has some good options and adequate software. This combination means that it should suit the needs of most users.

Gresham HF Line 4Board

The online Gresham unit is very large and very 70s-looking in its appearance.

There are no receptacles mounted on the rear of the device, as all connections are achieved through a standard four-gang unit connected to the machine.

This means that different cabling is not a worry and enables any item to be plugged into the UPS. This UPS is able to output 3,600Va of power.

All the management options are utilised through the RS232 port located on the rear of the unit. No network adaptor was provided and there are no slots in the back in which to insert any type of cards. The lack of a network option reduces the complexity of setup, as things such as assigning IP addresses are not an issue.

Located below the management port are two nine-pin D-Sub-type connectors, which allow remote control options to be added to the device at a later date.

Provided with this UPS are two pieces of software: one for management and the other to control the operating system shutdown. The management software, Meta Link, enables connection to the UPS using a serial cable and allows the user to view current operational status and change various parameters.

Running the software allows items such as the current input and output power levels to be viewed. It is also possible to change options, such as the maximum time that the UPS is to run on battery power. When this time limit has expired, the UPS will shut down.

The shutdown software is called UPSMan. It installs itself as a service, with options accessed through the Windows NT control panel. However, this is a very basic shutdown program. The only options are the shutdown time - dependent upon how much battery power is left - and an option to run up to three programs of the user's choice.

The software, therefore, provides the minimum requirements to make sure that a server shuts down correctly, performing the job perfectly adequately using basic management tools.

Liebert UPStation GXT

With four receptacles giving an output rating of 3KVa, the online Liebert UPStation GXT is no slouch. An expansion slot located on the rear of the unit was occupied by an SNMP network card. The card, in addition to an RJ-45 port for the network connection, has a DB9 serial cable connection.

The card is configured utilising this and the serial cable provided.

Using a standard terminal package, the card can be given an IP address and the necessary information to allow management via SNMP. Liebert provides software called SiteNet SNMP to run under various management packages, such as HP Openview.

SiteNet SNMP is strictly a management-only package. It shows a diagram of the power running around the UPS, plus current battery information.

The SNMP settings can also be changed using this package, as well as running UPS and battery tests.

Shutdown software, such as SiteNet 2, can be downloaded from Liebert's Website. SiteNet 2 requires a slightly different cable, but Liebert has included this as part of the bundle.

SiteNet 2 offers more management tools, including the animated display of power in the UPS. It allows diagnostics tools to be run, as well as logging events, and enables shutdown information to be configured. The documentation provided with each of the software systems is very well written. It covers everything from getting the software installed, to using it to manage the Liebert UPS, and is basically a version of SiteNet SNMP with the shutdown software included.

The network card option makes the Liebert a good contender, as with it, the UPS can be managed from across a network by a different computer.

This makes an administrator's job significantly easier. The fact that Liebert supplies three different types of software means that when buying a UPS from the company, the user only has to get hold of the software needed - meaning fewer redundant pieces of software lying around.

MGE Pulsar Esv 22+

The line-interactive model provided comes as two units: the main intelligence and an extra battery pack. Despite being very small, it has six receptacles that can output 2,200Va, which is more than capable of sustaining two tower servers plus some external storage.

The manual contains a graph describing the amount of autonomous power that can be expected, based on the peripherals attached. There are two RJ-45 connections on the rear, allowing the user to protect a single network connection.

The front of the device has a collection of LEDs giving information on its current status. Should power fail, these LEDs will show how much power is left in the battery in four steps: 100 per cent, 75 per cent, 50 per cent and 25 per cent.

This model can be fitted with a network card, allowing the unit to be managed by SNMP. Initial configuration has to be performed through a terminal package using the RS232 port located on the rear of the machine. This allows the network card to be given an IP address, although the instructions are a little unclear. Once an IP address has been assigned, the UPS can be configured via Telnet.

MGE's management package monitors the status of the UPS through a graphical, colour-coded image of the device. The colours turn red if there is a problem.

Clicking on a specific area reveals more information.

The software that really shines is the shutdown program, which is hugely configurable. Each problem is saved as an event and users can choose an action to be performed should an error occur.

The software will, of course, shut down the machine that it is running on should the user configure it to do so.

This is a well-designed UPS, both software and hardware-wise. Its small size also allows it to be stored almost anywhere.

Powerware NetUPS SE

Containing six receptacles on the rear and an output rating of 1,500Va, the NetUPS SE is a very capable UPS. All this is impressively stored inside a tiny case, making storage no problem at all. The model comes as a single unit with communication carried out via the provided serial cable. Powerware also sells SNMP adapter cards, which plug into the upgrade slot on the rear of the machine, allowing the network to be utilised for management options.

The front panel of the device features three banks of LEDs, giving at-a-glance information on the current status of the UPS. Each set of LEDs goes from green to red, allowing the user to easily see if there is a problem that needs to be dealt with. The banks indicate the load level, the current battery charge and input type. The front panel also includes the necessary buttons to turn the UPS on and off, as well as turn the audio alarm off.

The NetUPS SE gives complete protection to a server, even to the extent of having a network surge protector. This simply has two RJ-45 connectors, one to plug into the PC and one to plug into the network - a nice feature which helps provide good, all-round protection.

Powerware provides two software packages on a single CD, which support a huge number of operating systems, from NT and Unix to even Linux - an option that the company claims is unique. The packages are fairly similar, with the exception that one, LanSafe III, is for use across a network.

As the tests mostly used a single machine - a Windows NT server - the Labs looked mostly at FailSafe III.

This software is very good and performs the two options needed for a reliable, unattended shutdown of a server and power management facilities.

On loading, FailSafe presents a graphical view of the current UPS status, allowing the user to see the input and output voltages, plus how power is running through the device. Reliability of a UPS is an important factor, especially considering that batteries do wear down. With this in mind, the software allows diagnostics tests to be run on the hardware.

Perhaps the most useful function of the software is the ability for it to safely, and in a controlled manner, shut down the machine that it is connected to - an area which it covers very comprehensively. When it comes to shutting down a computer, the user is presented with three timings to set, called wink time, countdown time and shutdown time. Wink allows a minimum time limit to be set, whereby power fluctuations lasting less than this time are not reported.

Countdown time is the length of time after power fails before shutdown of the machine begins, and then how long physically shutting down takes.

This enables the user to configure the system to work according to the environment that it is situated in.

The software has been designed to react to a large range of events, such as power failures and communications errors. Each one of these presents the user with a message. This is totally customisable, with the option to send commands to a modem. It's nice to see all of these extra options, as they allow a user to get everything working in the exact way that they want.

Overall, the NetUPS SE is a well-built UPS with outstanding management software.

PK US9001

The online PK US9001 unit has a very clever design. The main unit houses up to four batteries, allowing for a maximum of 4,000Va output. The model that we tested comes with three power units and each one can be used as a 1,000Va UPS by itself, or combined into the cabinet to form a single UPS.

Cabinets can be bought in various sizes to provide more or less power, and simple batteries can be plugged in, instead of the power units. The LEDs mounted on the front of the cabinet indicate the current status of the UPS, such as if it is running off mains power and if there is a fault in one of the power modules. Despite the maximum power that this cabinet can deliver, there are only two receptacles located on the rear of the device.

This is yet another unit that has no network interface, so all of the management facilities are achieved using a serial cable attached to the RS232 port on the UPS. PK provides two systems for dealing with management - Smartmon or Powermon II. The management software provides all the expected functions, such as the ability to check the status of the battery, as well as performing tests on the UPS. All of the events that occur can be written out to a log file, allowing an administrator to track down problems.

The shutdown part of the software is quite basic - simply select the time at which the server is to shut down. In testing, the software did its job, but it would have been good to see a slightly larger range of options.

The PK US9001 is a well-designed UPS and its modular design allows for easy upgrade. Power units can even be pulled out and used by themselves on a different machine. This very flexible unit should suit most people, but more advanced software would have been useful.

When all is said and done

Although UPSs are nothing but big, clever batteries, they are a vital part of a network.

The hardware side of UPSs is now a fairly stable platform, so this benchtest concentrated on the software. Today's UPSs come with software that can safely shut down a network, along with a whole host of options that react to other incidents, such as excess humidity, break-ins and power fluctuations.

All of the UPSs in this test did their job, but special mention must go to the APC SmartUPS. This is due to its simplicity of approach to Web-based and SNMP management, its excellent shutdown software and its range of monitoring options.

Two UPSs are recommended: MGE's Pulsar ESV 22+ is a great machine which comes with management software that is both easy to use and informative, while the Powerware NetUPS SE is superbly built with excellent management software.

By David Ludlow. This article previously appeared in Network Solutions, February 1999.

POWER TO THE PEOPLE: THE OPTIONS AVAILABLE TO DEALERS

UPSs fall predominantly into two categories - online and offline.

An offline UPS is also known as a standby. Both types are hardware-based - although there are some basic software-based power protection products on the market - and provide immediate battery backup in the event of a complete power-down.

Fundamentally, the two differ only in two respects: the amount of time they allow a system to continue running without mains power supplies and the 'load' - the level of electrical requirement they are capable of supporting.

The machines can't run a mainframe or a server farm off one 240V socket.

The difference between online and offline is the normal power source.

In an online UPS, 100 per cent of the load current is always supplied to the computer system via the UPS. This enables the UPS to act as a line concentrator as well, ensuring a constant level of power is supplied to the system.

With an offline UPS, the load current is fed in the normal way from the mains power source to the computer, unless there is a power failure or disturbance. The UPS senses this and immediately takes over from the normal supply.

All UPSs, whether online or offline, have a similar architecture. Their 'building blocks' may be different sizes and configurations, but the component parts are essentially the same.

It is important to understand that most kinds of UPS are not designed to replace power supplies for any longer than is necessary to shut the system down safely. Most will give users between 10 and 30 minutes, during which any work currently resident in memory can be saved and the computer can be shut down.

Most UPS systems now come with an automated alerting system, which will warn the system administrator when a problem has occurred. Several methods can be used to alert the user, from audible alarms to automatically dialling an emergency telephone through the computer. Alerts may also appear on the administrators' screens.

Even in large installations with a dedicated backup generator, a UPS may be needed to allow time for the generator to kick in. At best, this will take several seconds, by which time the damage to the computer system could already have been done.

Offline

In an offline UPS, the unit is connected to the mains power and sits between the computer and the source, but most of the time it is inactive. When the mains power supply is interrupted, the UPS senses the disturbance and switches the power to its backup battery supply almost immediately. The switchover takes about four milliseconds - more than fast enough for a normal PC to stay up and running without any problem.

The comparatively simple design and construction of the offline units makes them much less expensive than online ones, but they offer fairly low levels of power conditioning and are limited in the load they can manage.

Line-interactive or ferroresonant A variation of offline UPSs, line-interactive units offer an enhanced level of power protection by constantly monitoring the quality of supply to the computer.

The inverter - the part of the UPS that 'cleans' or conditions the power supply - has an embedded microprocessor that manages the process. Line interactive models also have a crude voltage regulator that will boost power supply if the power supply should be reduced, or cut it down if a surge is detected.

This ensures that any disturbance is corrected instantaneously. During a surge, a line-interactive UPS will spread the extra voltage evenly across the load until it reaches a predetermined safe level. If the voltage goes beyond this level, the UPS will switch to battery power to protect the critical load.

Line-interactive systems can offer a moderate level of protection against high-voltage spikes and other events, without offering complete isolation of the load. As such, this kind of machine should provide an acceptable, if not comprehensive, power conditioning protection for most office systems - certainly at departmental level. (see p56)

MORE POWER TO THE PEOPLE

Online

Online UPSs are considered the premium option and, as such, are the most expensive. The UPS provides continuous power to the protected load, with its inverter always fully supporting the system. Power is still supplied from the mains but at all times via the UPS, allowing it to condition the power on its way to the protected systems and monitor against outages.

Online units use a double conversion method of power conditioning. The power supply is pushed through the UPS and changed from AC current to DC and back again, ensuring a much purer and more reliable supply to the critical load.

Online UPSs provide complete isolation of the load from most types of energy problem and provide seamless transfer from one supply to the other.

As the UPS is permanently online, the transfer time in the event of a power event is virtually undetectable. Some online products are now equipped with a reserve supply should the inverter ever fail, ensuring the load continues to be provided with sufficient power.

This built-in redundancy could be worth buying into as it provides contingency for maximum system uptime.

For true resilience and the only realistic course for protecting essential systems such as online processing, an online UPS is the most comprehensive option.

For extra proofing, products are coming onto the market that have even further built-in redundancy, which can take the UPS' mean time between failure (MTBF) rate from about 50,000 hours to more than 200,000 hours. Some manufacturers now claim to offer 99.9999 per cent reliability.

Digital UPS

This is the latest type and configuration of UPS which combines the performance features of an online UPS - such as the higher level of power conditioning and zero transfer time between mains and battery - with higher efficiency and a lower initial purchasing cost.

Like an offline system, the battery in a digital UPS is not online, so it's cheaper both to purchase and run. However, the digital model employs a digital switching mechanism that monitors the inverter thousands of times a second for any inconsistencies. In the event of a power failure, the digital switch allows the power to fail over to battery in a time comparable to that of an online system.

Digital technology is cheap and efficient. This type of system has become popular in the protection of mid-range installations, such as electronic point-of-sale, and looks set to provide an area of natural future growth for the technology at the low end.

It looks likely that in the future, offline UPS systems in their current form will become all but extinct. Online technologies with built-in power redundancy are likely to become the standard technology for several years.

Modular and redundant

A relatively recent school of thought, UPS redundancy is a way of providing power protection for the power protection system, which has been made possible by the development of modular designs.

The UPS designed for redundancy makes it easy to hot-swap individual units on the network. When one UPS is made non-operational, another continues to support the critical load.

And if a UPS should fail, the redundant UPS continues its mission, which is to provide uninterrupted power. If a conventional UPS fails, the system may be at risk if the power fails while waiting for the spare part. Redundancy ensures the system is not put at risk while changing a module, repairing the UPS or carrying out maintenance.

The modular design of this type of UPS makes removing and replacing a board quick and easy - the process takes a minute or less. Modular devices also tend to be lightweight - between 8kg and 16kg, depending on the rating, including battery - so ease of portability is another benefit.