Power protection maintenance issues

Colin Griffiths, customer service manager at power quality management specialist Advance-Galatrek, considers the importance of an enterprise-wide power maintenance policy

Only a few years ago, power protection was an issue that often meant little more than buying an uninterruptible power system (UPS) for those annoying instances when the mains power supply failed, so that production could continue more or less unabated.

The advent of voice and data processing, mobile comms, and critical equipment in sectors as diverse as healthcare and the rail industry has changed all that.

Nowadays, our total reliance on sensitive electronic equipment, whether installed in a hospital, data centre or at the railway trackside, means that what was once referred to as simple power protection has become much more significant.

Because we demand 99.999% dependability from our essential data processing systems, we can legitimately regard power quality management as being one of the most important issues facing industry in the 21st Century.

Of course, the concept of power quality management encompasses more than just the equipment supplied to mission-critical industries such as the computing, IT, mobile and telecoms sectors.

While it is true to say that choosing good quality equipment in the first instance can only aid reliability in the long term, even the best equipment requires service and maintenance from time to time.

This is the main reason why, when we examine the discipline that is power quality management, we need to consider not just the equipment itself, but also the wider implications of maintenance and servicing.

What this means is that power quality management is truly an holistic concept.

Both equipment and maintenance should be an integral part of a well thought out power protection strategy.

As such, it seems folly to separate the one from the other because, after all, who is better placed to understand your maintenance requirements than the company responsible for designing and supplying the equipment in the first instance.

But, like everything, the answer to that question isn't quite as straightforward as you might think.

In fact, this is where a lot of companies need to exercise some caution when deciding on their maintenance programme and, more importantly, who should be contracted to run it.

And becomes an area where knowledge and experience are the determining factors in choosing where to outsource your service issues.

Step one has to be choosing a company that has a proven track record in all aspects of power protection.

Because today's power chain equipment comprises devices ranging from UPS right through to generators, surge suppressors and DC power supplies, companies need to have the reassurance that their service supplier has amassed the appropriate experience with each product.

If not, the blunt answer is that they are simply not qualified to do the job.

The next stage to consider is the breadth of service on offer.

Is the organisation offering a fully featured maintenance contract, or are its services assembled in a piecemeal manner? If a maintenance contract is offered, is there a guaranteed call out response time? If so, does this fit in with your requirements? After all, you'll probably need to pay extra for a guaranteed fast response.

It's worth checking whether this is actually necessary, given your individual circumstances.

On the other hand, essential or critical services need to be able to rely on a very rapid response to ensure minimal disruption.

The third step towards maintenance heaven is, when call out actually takes place, what does the engineer actually do? It may not surprise the more cynical to hear that the actual levels of servicing and preventative maintenance that are undertaken can vary hugely from company to company.

Let's take UPS as probably the best-known example.

The service engineer should ideally be checking the complete UPS installation and not just the device itself.

So, maintenance needs to encompass the UPS bypass installation, the UPS itself, the batteries, any logs that need to be checked and the front panel controls, if fitted.

Proper operation of the bypass circuitry is almost as important as the correct functioning of the UPS itself.

If an external bypass switch is fitted, this needs to be checked for correct operation, as well as its overall physical condition, including issues such as the tightness of the terminals.

For the UPS itself, similar attention to detail needs to be taken.

A physical inspection of the fans and ventilation slots needs to be made, to ensure that there are no obstructions to these vital cooling ways.

Similarly, for those models that feature forced air cooling, fan operation needs to be inspected, and remedied if necessary.

Other UPS components that must be checked include printed circuit boards and wiring, for any signs of heat damage and wear, and to ensure that all connections and earth points are tight.

In addition, engineers must check that any oil filled capacitors are not leaking, and that any internal or external chargers are functioning correctly.

It almost goes without saying that an effective service programme will also check the input and output UPS voltage, and calibrate the battery voltage as necessary.

The issue of battery testing is probably one of the most overlooked - and yet most important - ones of all.

Many older UPS and DC standby power systems have few, if any, intelligent battery monitoring facilities.

As such, battery testing and maintenance is an essential element in helping to improve the reliability of these devices.

Although the batteries installed in critical applications such as telecom, mobile, Internet and cable installations may have been installed on the basis of their five or ten year design life, their actual working life may be far shorter.

This can depend on a number of variables, including actual usage in anger, the charging regime adopted and the local ambient temperature.

Because any of these factors can conspire to reduce battery life, the only alarm indication that the battery cannot support the intended application may be just before a mains failure occurs.

Even though many modern power protection systems incorporate basic battery testing functions, these devices tend to be less capable of identifying individual battery cell failure, especially within long duration battery sets.

As we know, any battery pack is only as good as its weakest cell, so any failure or performance shortfall in an individual cell can quickly damage the performance of the remainder.

This alone can make a battery maintenance programme worthwhile, as it will identify single cells that are putting the battery set at risk, and will therefore reduce the likelihood of needing to replace the whole set at an earlier than expected date.

Equally, there is a large field population of less sophisticated devices that have no integral battery monitoring facilities.

Because of this, users of these systems are frequently unaware that these devices are failing to operate to specification, leaving them with serious problems, should a mains failure occur.

In these circumstances, mission critical systems could crash immediately and without warning, just as soon as a mains interruption takes place, and the batteries are placed under load.

It hardly needs to be said, but the consequences could be disastrous.

One final alternative that needs to be explored is the latest trend towards 24/7 remote site monitoring.

Nowadays, power systems can be installed together with an additional device that is connected between one of the remote monitoring ports on the UPS or standby power system and a telephone socket or equivalent mobile communications device.

Essentially, this provides continuous monitoring of the device for potential alarm conditions, and hence gives the service centre remote access to the installation for maintenance purposes.

Monthly site activity reports can be collated, and the system can even ring or page engineers the moment a maintenance issue arises.

There is one slight note of caution, however.

Although this development provides us with an ideal theoretical advantage, it needs to be augmented by sound practical back up.

After all, what's the point of having a state of the art communications channel, capable of informing us of the slightest performance shortfall in our power protection chain, if there's no one on the other end of the mobile phone or bleeper? So, organisations looking to implement these innovations need to ensure that they only outsource to a reputable third party.

The message, therefore, is loud and clear.

Modern organisations need to look at power quality management as being an all-encompassing discipline.

While the hardware itself is an important element of any power chain, it is also true to say that maintenance issues are just as significant.

Provided that companies remain aware of the need to consider the two together, they will not only save money on the needless replacement of equipment, but will also have a more efficient system in place for when the inevitable happens.

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