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Frequently Asked Questions

What are the different types of UPS?

There are three basic types of UPS: On-line, Line-interactive, and Standby. Each type has it's advantages, and each has it's place.

Can the UPS notify me when a power problem occurs?

Yes. There are a number of options available. Shutdown software runs on your server and will broadcast messages or email you. There are also systems to interface into your existing SNMP or pager network. Power Tech Smart Monitor extends on this concept by incorporating environmental monitoring functions with software shutdown reporting.

Can I support my laser printers?

Laser printers draw a lot of power, especially when they are warming up. Therefore they require larger, more expensive UPS to power them. For most applications, it is not critical that laser printers be backed up.

What is the UPS's "bypass mode" for?

"Bypass mode" is a benefit of on-line UPS systems. It allows the UPS to continue supplying power to the load, even when the UPS is overloaded. Whenever you see the "Bypass" or "Load Unprotected" indicator lit, contact Power Tech for assistance.

What is the external maintenance bypass switch for?

The external maintenance bypass switch provides a simple method for your Power Tech service engineer to maintain your UPS system, without the inconvenience of shutting down your operation. Routine maintenance, battery checks, servicing, even complete UPS replacement can be performed without affecting your system.

I have some surge suppressing power boards - do I need UPS?

Surge suppressors protect you from certain types of surges and spikes. They don't protect you from sags and other power problems. And they don't provide you with back-up power.

Power protection is expensive. How much should I budget for UPS?

Power protection can be expensive - initially. However, downtime is more expensive. American studies place the average cost of downtime at US$60,000/hour for American business. Depending upon the level of availability required, around 7% of the total hardware budget should be allocated for power protection.

I'm installing the UPS in a rack. How should I orient the UPS?

Power Tech provides rack mount kits for the Compact series UPS. These are designed to ensure correct and secure mounting of the UPS in a 19" equipment rack.

What support options are available?

Power Tech Systems has a wide variety of support options available, from case-by-case return-to-base or on-site service, to on-site exchange programs, preventive maintenance visits and on-site service agreements. The size and type of installation you have will determine the best support option for you.

What is the expected life of my UPS?

UPS systems have only two "consumables". The batteries you rely on to provide you with power when mains fails have a service life of 3-5 years. After this time they need to be replaced to ensure your UPS gives you the run time you expect.

The cooling fans used in UPS should be checked for bearing deterioration at the same time as the battery, and replaced if necessary. Lastly, the DC-bus capacitors used in your UPS may need replacing after about 8 years of operation.

How much battery support time should I expect from my UPS?

The actual battery time received depends on a number of factors. Most UPS are rated at between 5 and 10 minutes when fully loaded. Most UPS are not fully loaded however, and actual battery support time is usually somewhere between 10 and 30 minutes. It's important to remember that a UPS is designed as an emergency system, not a replacement for mains power.

How long do the batteries take to recharge?

On most UPS, the batteries can be fully recharged within about 10 hours. Battery recharge time is affected by the amount of batteries in the UPS, so a UPS with extended batteries will take longer to recharge.

What type of batteries are used in a UPS?

Almost all modern UPS use maintenance-free, sealed lead acid batteries. Sealed lead acid batteries are very reliable, easy to maintain, and do not suffer from "memory effect" like some other type of rechargeable battery.

What is the service life of the UPS battery?

The maintenance-free sealed lead acid battery in your UPS has a rated life of between three and five years. UPS battery life depends on the number of charge/discharge cycles the battery goes through, and the temperature and humidity of the UPS environment.

Do I need to cycle the UPS battery?

No. The batteries in your UPS are "float charged." This means they are charged whenever mains power is available. As UPS batteries do not suffer from "memory effect", they do not need to be discharged and recharged by the user.

I am going to store my UPS. What do I need to do to preserve the battery?

When storing your UPS, you should charge the batteries every three months. This ensures that the battery does not become damaged due to lack of use.

If the batteries are not charged regularly during storage, you may find they need replacing when the UPS is re-installed.

Can I replace the UPS batteries myself?

The voltage of the battery system in your Power Tech on-line UPS is above the safe limits for user-replacement. Attempting to replace the batteries in your UPS could result in extreme damage to the UPS. Failure to follow the correct procedure may result in severe burns and serious injury.

For this reason, a Power Tech field engineer must replace the batteries in your UPS.

How much battery time do I need?

One important thing to remember about UPS is that it is designed as a back-up, not a replacement, for the utility mains. Your UPS should provide power long enough to alert all your users to the power failure, log everyone off, and perform an orderly system shutdown.

Keep in mind that while such a procedure used to take around an hour, modern systems can be shutdown much quicker.

Also keeping in mind the fact that UPS batteries need to be replaced every 3-5 years, a typical installation may only need around 10-15 minutes battery time.

How can I measure the battery time my UPS offers?

The most accurate method of measuring battery support time is to perform a battery discharge test. Schedule a time that suits your organisation, and ensure that your computer system is "safe." Now remove mains power, and measure the battery support time provided by the UPS. When the UPS enters "Low Battery" mode (the audible alarm sounds every second, as opposed to every 4 seconds), restore mains power.

This test should be performed every six months. Battery discharge tests are included in our On-Site Gold maintenance agreement. Your Power Tech service engineer will be able to perform battery discharge tests for you.

How will I know when to schedule battery replacement?

Record the results of your battery discharge tests. After three years or so, the battery support time provided will become noticeably shorter. When the support time provided is no longer acceptable, battery replacement should be performed.

Battery discharge tests are included in our On-Site Gold maintenance agreement. Your Power Tech service engineer will be able to guide you in scheduling battery replacement.

I have a UPS, why do I need a generator?

Your UPS is designed to protect you from mains power disturbances, and to provide emergency power in the event of a mains power outage. A UPS is not designed as a replacement for mains power. If long term support is required, then we recommend you consider a generator in conjunction with your UPS.

I have a generator, why do I need a UPS?

A generator is designed to provide medium to long term emergency power in the event of a mains power outage. However, a generator is not designed to protect you from power problems, and may not provide computer quality power. Also, a generator can take minutes to start up. For continuous, clean power, a Power Tech UPS should be used in conjunction with your generator.

My UPS is rated at 1kVA, what size generator do I need?

For maximum stability, your generator should be at least twice (preferably three) the size of your UPS.

Can I attach air conditioning and other equipment to the same generator as the UPS?

Yes, provided the total load does not exceed the generator's capacity. Also, the start-up current of the load must be less than twice the generator rating. Power Tech recommends that a generator load analysis be performed to confirm generator requirements.

Of the different types of UPS, which are best suited to generator operation?

As generator output can vary widely, Power Tech recommends on-line UPS for generator operation. On-line UPS accept a wide range of input voltages, and do not drain their battery when the generator voltage is outside acceptable limits.

What voltage specifications should I look for in a generator?

In order to be compatible with your Power Tech UPS, your generator's output voltage must be in the range of 240VAC -20% +15% (192 to 276VAC).

What frequency specifications should I look for in a generator?

In order to be compatible with your Power Tech UPS, your generator's output frequency must be 50Hz ?% (47.5 to 52.5Hz). For 60Hz systems, your generator's output frequency must be in the range 57 to 63Hz.

What other features should I look for in a generator?

Generator stability is vital to correct operation with a UPS. An electronic governor can help regulate generator function to maximise generator stability.

My generator has poor stability. Will this affect the UPS? Why?

If your generator is not providing stable power, the UPS will not be able to synchronise it's power with that of the generator. This may cause problems should the UPS become overloaded.

If the UPS is not synchronised to the supply it is receiving from the generator, the UPS may not be able to transfer the load to "bypass" or "load unprotected" modes cleanly, should the need arise. This in turn may result in an unscheduled power interruption.

Which Power Tech UPS models work best with generators?

All Power Tech UPS systems have been tested with generator systems and are compatible. However, Power Tech's PT UPS 10001T model uses controlled rectifier technology, and requires that the generator supply be as stable as possible to maintain synchronism.