It's always worth investing in a UPS battery pack

By Zatni Arbi

JAKARTA (JP): Each time I have to burn the midnight oil to complete a job, the circuit breaker for my electrical power flips off at least once every hour. That's because the power that I can use at home is limited to only 2,200 watts. With two room air conditioners running, no matter how many lights I switch off -- and I even unplug the fridge -- I'm bound to cause an electrical overload.

What saves me each time is that I have an uninterruptible power supply, or a UPS, for each of the two PCs that I use. Each time the light goes out, the monitors, the scanner, the laser printer, etc., will stop working, but the PCs will remain alive. Whatever job I'm working on is not lost.

I bought my locally-made ICA UPS in August 1992, after frequent electrical outages damaged my Micropolis hard disk and put it to rest in peace eternally. At that time, a plain-vanilla UPS still cost a fortune, so buying it was really a tough decision. Today, as in the case of the PC itself, the price has gone down and more features have been added. Also, we now have many competing brands of UPS, both local and imported, on the market.

The fact is, although we may have political stability in this country, we still don't have power line stability. Those who come from advanced countries may find it unbelievable that the electrical voltage fluctuates more violently than the flood water along Jalan Mangga Dua Raya (well, to be fair, now that the construction of the huge buildings is nearing completion and the road is being repaired, we don't have as many floods there as we used to).

In addition, a lot of people are misled into believing that the cheap, Rp 70,000 stabilizer that the computer store usually bundles in with any purchase of PC, provides sufficient protection to the purchaser's investment. Unluckily, that's not the case. A stabilizer only attempts to regulate the current by compensating for the sags and brownouts. But when there is a power outage, the stabilizer will not help.

I was even told once that the stabilizers you can buy at Glodok or anywhere else in Indonesia did not exactly protect your electronics from power instability. They might just give you a false sense of safety. Whether this is true or not, I cannot verify because we still don't have an independent testing agency such as the Underwriter Lab in the U.S. Therefore, in my opinion, no high-end PC should be used without a UPS, period.

Why UPS

A UPS is basically a rechargeable battery pack that supplies power to the computer and its peripherals in the case of power droppage. When the light is OK, the battery is recharged.

But remember that even a UPS cannot give full protection to your PC. If, for instance, lightning strikes near your house, no matter how expensive and sophisticated your UPS is, you may have to say goodbye to your beloved PC forever. This power line problem, usually called a spike, can be very harmful to electronic components.

Nevertheless, having a UPS is definitely better than not having one. Here's an example of why it is necessary to have a UPS: From time to time we have to defragment the files on our hard disks in order to maintain the PC's performance, because heavily fragmented files will significantly reduce speed of data access. Should a blackout happen exactly at the moment the computer is writing into the hard disk's File Allocation Table (FAT), this important file can become corrupted and you may no longer be able to read the hard disk at all. Another potential disaster can happen if you use a password and the password data is corrupted, you won't be able to access your hard disk.

And, even here in Jakarta we have power outages happening without any warning. A week ago, as I was defragmenting one of my hard disks, the light went out. It turned out that some crew of the PLN decided to replace one of the utility poles without notifying us in the neighborhood. Fortunately the PC drew power from a more expensive APC UPS, so it stayed alive and worked hard until the lights came back 10 minutes later. Had it stopped short of the 10 minutes, I would have lost all the data on the hard disk I was optimizing.

Today, my three-year-old ICA UPS can supply the power to my loaded 486 BL machine up to only five minutes. That still gives me enough time to search for my flashlight and go outside to switch the breaker back on. I could have the battery elements replaced, but I don't think that's necessary yet. As long as the UPS keeps the PC running while I switch the breaker back, that's enough for me.

Different types

There are basically two types of UPSs: Standby and Continuous. Standby UPS provides power only when it detects a significant drop in power voltage. The switching speed is extremely important, since the operation relies on how fast the battery takes over. Fortunately, computers usually have built-in reservoirs that are called capacitors; they keep the computers working between power replenishment. The latest generation of PCs are reportedly capable of tolerating power interruption up to 200 ms. Most quality UPSs switch to battery power within 8 ms.

When buying a UPS, ask whether the output is a square wave, a sine wave or a step sine wave. Avoid the less expensive UPSs that have square wave output, as this kind of output creates stress on components. Choose UPSs with sine or stepped sine wave output.

UPSs also differ according to the amount of power it can supply. If you wish to be able to continue working for a couple of minutes before shutting down your PC, you may need a UPS large enough to supply power to your monitor as well. Keep in mind that most UPSs are rated to provide power for 20 to 60 minutes.

Most low-end UPSs can supply 250 watts of power, and as the amount of power increases the price increases much more rapidly. For most of us, a UPS of this capacity is sufficient.

Internal UPSs

Back in early 1990s, PC Power & Cooling already marketed an internal UPS that came in the form of an expansion card. At that time I thought every high end PC in the future would be sold with this UPS installed. But I'm truly surprised that today people seem to drop the idea of having internal UPS built-in into a PC. One possible reason I could think of is that PC manufacturers are not really interested in making their products too durable!

Today, UPSs are getting smaller and less obtrusive. Right now you can buy a UPS that you can place right underneath the monitor, such as the one you see in the accompanying picture. The price is also about the same as a mid-range computer monitor. The frustration it can save you can be immeasurable. So, the conclusion: Add a UPS to your PC.