Question 1

What is a UPS?

Accepted Answer

An uninterruptible power supply, also uninterruptible power source, UPS or battery/flywheel backup, is an electrical apparatus that provides emergency power to a load when the input power source, typically the utility main, fails.

Question 2

How many types of UPS are there?

Accepted Answer

There are three typical types of UPS: OFF-LINE, ON-LINE, and LINE INTERACTIVE.

Question 3

What are an "ONLINE UPS?"

Accepted Answer

An Online UPS takes incoming power, converts it to DC, conditions it, and converts it back to AC. This means the UPS is Online since there is no delay to switch to battery. Use an online UPS for your critical applications, high availability servers, etc. The output of these online UPS systems is a TRUE sine wave and is usually better than power from the electric company.

Question 4

What is called “Offline UPS”?

Accepted Answer

In this type of UPS, the primary power source is line power from the main utility, and the secondary power source is the battery. The battery charger is using line power to charge the battery, and the battery and inverter are waiting “on standby” until they are needed. When the line power fails, the transfer switch changes to the secondary power source. When line power is restored, the UPS switches back

Question 5

What is called “Line Interactive UPS”?

Accepted Answer

Line Interactive UPS under normal conditions smoothes and to some degree regulates the input AC voltage by a filter and a tap-changing transformer. The bi-directional inverter/charger is always connected to the output of the UPS and uses a portion of AC power to keep the battery charged. When the input power fails, the transfer switch disconnects the AC input and the battery/inverter provides output power. Its typical efficiency is 90-96%. This type is currently the most common design in the 500 VA – 5000 VA power range

Question 6

What can a UPS do for me?

Accepted Answer

Every UPS will supply power to a load (such as a computer, telephone switch, or medical equipment) when mains power fails. It may also condition the power and prevent spikes, brownouts, interferences, and other unwanted problems from reaching the supported equipment

Question 7

Why do I need a UPS?

Accepted Answer

Power disturbances and blackouts can be costly.  Preserving Information, the availability of equipment critical to the business, maintaining fully occupied staff, reduction of cost over-runs, performing reliably, and getting results on time are all key elements in any successful operation.  A UPS will provide clean, stable power to critical application equipment throughout utility power disturbances and power failure.

Question 8

How long can a UPS keep my equipment running?

Accepted Answer

As long as you want, providing you buy enough batteries and the charging system is up to it. After about four hours it’s usually more cost-effective to buy a generator, with a short run time UPS to bridge the generator start-up gap

Question 9

What's the lifetime of a UPS?

Accepted Answer

Most plug-in UPS are good for at least five years. We’d advise you to change the batteries every three to four years. With larger equipment (and more substantial investment), the lifetime of the equipment increases. We maintain equipment that’s twenty years old and still going strong.

Question 10

How to maintain a UPS?

Accepted Answer

There are three simple methods:
1. Never overload your UPS.
2. Never connect any home electronic devices such as a cooling fan to your UPS. This may cause a malfunction of UPS.
3. Discharge the battery at a consistent interval. The best way to do it is once a month or once two months. The simplest discharge way is to turn on the UPS without connecting the mains

Question 11

Where I live seldom occurs power failure will I still need a UPS?

Accepted Answer

In fact, power failure is one of the power problems. The other power problems such as high voltage, low voltage, and spike are the main problems. The purpose of UPS is to provide customers the overall power protection such as voltage regulation, surge protection, spike, and sags protection. It also provides extended backup time without any limitations.

Question 12

What could I use for the RJ11 connector on the rear panel of UPS?

Accepted Answer

RJ11 connector is used to protect the phone line. Hence, you can connect your phone; fax machine, modem, and ADSL with it for better protection.

Question 13

How many kinds of Power problems?

Accepted Answer

Except for the blackout, there are Sags, Spikes, Surges, Noise & Transients will make the PC or other high technical equipment damage or shorten the lifetime.

Question 14

What kinds of equipment should I use with the UPS? Is there any limit for it?

Accepted Answer

Normally, the UPS is used for PC, high technical equipment & medical appliances. Because most UPS are designed for PC, so not all the equipment could be connected with it. Especially, conducting loads just like cooling fans, refrigerators that have motors. These kinds of equipment will damage the UPS. Moreover, copy machines and laser printers that have huge starting current also could not be used with UPS. The huge starting current will impact the capacity of UPS.

Question 15

What is the impact of different output waveforms?

Accepted Answer

There are three major types of loads: Resistive load (Lamps); SPS load (PC power supply) & Conductive Load (Motors). All the types of load can be used with Pure Sinewave. However, only Resistive and SPS loads can be used with Modified Sinewave.

Question 16

What is the impact on the PC with different transfer times?

Accepted Answer

Except On-Line UPS, there will be a short transfer time between 2ms to 10ms for the power transformation with OFF-LINE & LINE INTERACTIVE UPS. Normally, when the blackout happens, the power supply of the PC could continue the power for 16ms. Hence, most PC will still work functionally with the short transfer time.

Question 17

What is the battery type of UPS?

Accepted Answer

Most UPS use Lead-acid maintenance-free batteries. This kind of battery is sealed so the UPS can be located in any direction and it does not void the poison gas during charging and discharging. So it also could be an indoor installation.

Question 18

What is the lifetime of batteries?

Accepted Answer

The battery lifetime depends on the ambient temperature and the times of charging and discharging. Higher ambient temperature and too many charging and discharging times will reduce the lifetime. Normally, the battery lifetime is close to three years.

Question 19

How to choose the right UPS?

Accepted Answer

1. Understand the specifications of all UPS.
2. Consider the requirements of power quality.
3. Understand the current capacity of UPS and consider the future expansion.
4. Choose reputed brands and manufacturers.
5. Choose UPS based on your requirements.

Question 20

What are the important items you should evaluate when buying a UPS?

Accepted Answer

1. UPS reliability and stability.
2. The excellent engineers and the ability of product creation.
3. High efficiency and low noise.
4. Suppliers' reputation and financial situation.
5. International safety approvals such as TUV, UL, CSA, and so on.
6. Plant certifications such as ISO9001, ISO9002, and so on.

Question 21

What's the capacity of the battery?

Accepted Answer

The capacity of the VRLA battery means that when the battery is fully charged and discharge at some condition to the stated end voltage, the capacity is released out, the unit is Ah. For example, when the battery discharges at 1A current for 1 hour, that’s the 1Ah capacity. If the battery discharges at 4A current for 3 hours to the end voltage, the released capacity is 12Ah.

Question 22

When disconnecting a battery, which terminal should be disconnected first?

Accepted Answer

Originally Answered: When removing a battery from a vehicle, which terminal is disconnected first?
Always negative. Simple reason. The entire body of the car along with the engine is connected to the negative terminal of the battery. If you're disconnecting the positive terminal first, and the spanner touches any part of body or engine, you'll get a massive spark and potentially damage your battery also. By disconnecting the negative first, you eliminate the risk of *grounding” your battery on the car body or engine.

Question 23

What is epv (cut-off voltage/endpoint voltage)?

Accepted Answer

EPV is the battery end load voltage in the condition of discharge. Many kinds of standards rule EPV definitely in different discharge rates and temperatures. EPV is different according to different discharge rates: it is low when discharge in high current, contrarily, it is high when discharge in low current.

Question 24

What is the self-discharge rate of batteries?

Accepted Answer

The self-discharge, also known as charge retention capacity, means when it is in an open-circuit state, the maintainability of the battery’s storage electricity under certain environmental conditions. During storage time, the rate of capacity loss is called the self-discharge rate. It is mainly affected by the manufacturing technology, materials, storage conditions, and other factors, which is an important parameter to measure the battery’s performance.

Question 25

What is discharge hour rate?

Accepted Answer

Discharge hour rate means the discharging capacity will decrease according to the increase of discharge current under a condition that the active substance quantities keep unchanged. So, the discharge rate should be specified when scaling the discharge capacity. The discharge rate includes the hourly rate and current rate. Hour rate (time rate) is the needful time when finished discharge the capacity under a definite current, different VRLA battery have different discharge rate standard; the Current rate is also named as double rate, it is meaning that discharge current is the double rate of rating capacity.

Question 26

Why the batteries need to be stored for a certain time before delivery?

Accepted Answer

The storage capability is an important parameter for checking the stability of general capability. After a certain period, storage, the variety of capacity, and inner resistance are allowed. And the storage can level off the electrochemistry performance of the inner component, so that we can know the extent of self-discharge capability, then pick out the batteries with the short circuit (caused by the fast dropping of OCV) and micro short circuit, so the battery quality can be ensured

Question 27

Why the battery cannot be charged (fully charged)?

Accepted Answer

After using for a few months, the battery cannot be charged, because of the occur of Lead sulfate (PbSO4), sulfation as it is commonly called. Generally speaking, sulfation is the prime cause of battery failure and loss of capacity especially sulfation is a natural occurrence in all lead/acid batteries including sealed, gel-cell, and recumbent batteries. It the prime cause of early battery failure and is when the sulfur in the sulfuric acid forms sulfur crystals attach to the lead plates and then act as an “insulation” keeping the battery from accepting a charge. Typical chargers and even “smart or automatic chargers” cannot overcome this phenomenon and thus the battery is discarded as “not being able to hold a charge”. Sulfation occurs far more readily in hot climates where batteries aren’t frequently used or kept up to voltage. Sulfation can occur in brand new batteries in as short of the time period of a few weeks or a few months.

Question 28

How to avoid the plate sulfation?

Accepted Answer

1. Using an extended charge, known as an equalization charge to slow down the rate of sulfation
2. Avoid low cutoff voltage discharges
3. Recharge immediately after discharge
4. Completely charged before using
5. Please shelve the battery after it’s fully charged

Question 29

What is the advantages of lead acid batteries?

Accepted Answer

Technology progresses in the mid-1970s when researchers developed a maintenance-free lead-acid battery that was able to operate in any position. The liquid electrolyte was transformed into a moistened separator and the enclosure was sealed. In addition, safety valves were added to allow venting of gas during charge and discharge. Nowadays, life without lead-acid batteries seems implausible. They have myriad uses and are one of the most useful batteries with the longest life cycle, the greatest energy density per pound, and the most mature recycling infrastructure of similarly priced batteries.
The lead-acid battery has been used over more than 140 years, lead-acid batteries are reliable, mature secondary batteries, globally manufactured, and therefore a widely understood technology. When used correctly, they are very durable and dependable. Their self-discharge rate is among the lowest of rechargeable battery systems. Capable of high discharge rates, the lead-acid battery is able to deliver the bursts of energy that are required to start an engine.
Lead-acid batteries are environmentally sound in that they are recycled at an incredibly high rate. Today, 98% of lead-acid batteries are recycled. With low maintenance requirements, the lead-acid battery includes no memory and no electrolyte to fill on the sealed version.
In terms of these advantages of the lead-acid battery, they are widely used by many different industries, such as telecommunication, power systems, radio, and television systems, solar, UPS, electric vehicles, automobile, forklifts, emergency lights, etc.

Question 30

Does overcharge damage batteries?

Accepted Answer

Over Charging is the most destructive element in battery service. Usually, the boater is not aware that this is occurring as he believes his alternator or battery charger is “automatic.” Unfortunately, these automatic circuits are sensitive to voltage surges, heat, direct lightning strikes, and indirect lightening electromagnetic influences and could fail or shift their calibration. When they fail, overcharging begins to affect the batteries. During overcharging, excessive current causes the oxides on the plates of the battery to “shed” and precipitate to the bottom of the cell and also heat the battery, thus removing water from the electrolyte. Once removed, this material (which represents capacity) is no longer active in the battery. In addition, the loss of water from the electrolyte may expose portions of the plates and cause the exposed areas to oxidize and become inactive, thus reducing additional capacity. Sealed batteries are not immune from the same internal results when overcharged. In fact, sealed recombination absorption and gel batteries are particularly sensitive to overcharging. Once moisture is removed from the battery, it cannot be replaced. Portions of the battery damaged due to overcharging are irretrievable. However, if detected early, corrective adjustments to the charging device will save the undamaged portion of the battery. Initial signs of overcharging are excessive usage of water in the battery, continuously warm batteries, or higher than normal battery voltages while under the influence of the charger. If overcharging is suspected, correct immediately

Question 31

Does over-discharging damage batteries?

Accepted Answer

Over-discharging is a problem that originates from insufficient battery capacity causing the batteries to be overworked. Discharges deeper than 50% (in reality well below 12.0 Volts or 1.200 Specific Gravity) significantly shorten the Cycle Life of a battery without increasing the usable depth of cycle. Infrequent or inadequate complete recharging can also cause over-discharging symptoms called SULFATION. Despite that charging equipment is regulating back properly, over-discharging symptoms are displayed as loss of battery capacity and lower than normal specific gravity. Sulfation occurs when sulfur from the electrolyte combines with the lead on the plates and forms lead-sulfate. Once this condition becomes chronic, marine battery chargers will not remove the hardened sulfate. Sulfation can usually be removed by a proper desulfation or equalization charge with external manual battery chargers. To accomplish this task, the flooded plate batteries must be charged at 6 to 10 amps. at 2.4 to 2.5 volts per cell until all cells are gassing freely and their specific gravity returns to their full charge concentration. Sealed AGM batteries should be brought to 2.35 volts per cell and then discharged to 1.75 volts per cell. This process must be repeated until the capacity returns to the battery. Gel batteries may not recover. In most cases, the battery may be returned to complete its service life.
CHARGING Alternators and float battery chargers including regulated photo voltaic chargers have automatic controls which taper the charge rate as the batteries come up in charge. It should be noted that a decrease to a few amperes while charging does not mean that the batteries have been fully charged. Battery chargers are of three types. There is the manual type, the trickle type, and the automatic switcher type.

Question 32

What matters need attention during battery installation?

Accepted Answer

- Batteries should be put in a dry and ventilated place (at no time should they work in a sealed container), keep away from direct sunlight and any kind of heating.
- Use insulated tools when installing the battery so as to avoid shock accidents.
- Fasten all bolts tightly when installing connecting wire to illuminate the occurrence of sparks.
- Keep a minimum distance of 2CM between batteries, otherwise, the wires may be overheated by any chance.
- It is recommended that the battery be connected in series with the same type that has an equivalent amount of capacity.
- Only batteries or battery bands that have the same nominal voltage and capacity can be connected in parallel (Parallel is not favorably advised).

Question 33

What is a lead-acid battery?

Accepted Answer

Voltage: Voltage is an electrical measure that describes the potential to do work. The higher the voltage the greater its risk to you and your health. Systems that use voltages below 50V are considered low-voltage and are not governed by an as strict (some might say arcane) set of rules as high-voltage systems.

Current: Current is a measure of how many electrons are flowing through a conductor. Current is usually measured in amperes (A). Current flow over time is defined as ampere-hours (a.k.a. amp-hours or Ah), a product of the average current and the amount of time it flowed.

Power: Power is the product of voltage and current and is measured in Watts. Power over time is usually defined in Watt-hours (Wh), the product of the average number of watts and time. Your energy utility usually bills you per kilo Watt-hour (kWh), which is 1,000 watt-hours.

A lead-acid battery is an electrical storage device that uses a reversible chemical reaction to store energy. It uses a combination of lead plates or grids and an electrolyte consisting of diluted sulphuric acid to convert electrical energy into potential chemical energy and back again. The electrolyte of lead-acid batteries is hazardous to your health and may produce burns and other permanent damage if you come into contact with it. Thus, when dealing with electrolytes protect yourself appropriately!

Question 34

Deep cycle vs. starter batteries?

Accepted Answer

Batteries are typically built for specific purposes and they differ in construction accordingly. Broadly speaking, there are two applications that manufacturers build their batteries for Starting and Deep-Cycle.

As the name implies, Starter Batteries are meant to get combustion engines going. They have many thin lead plates which allow them to discharge a lot of energy very quickly for a short amount of time. However, they do not tolerate being discharged deeply, as the thin lead plates needed for starter currents degrade quickly under deep discharge and re-charging cycles. Most starter batteries will only tolerate being completely discharged a few times before being irreversibly damaged.

Deep Cycle batteries have thicker lead plates that make them tolerate deep discharges better. They cannot dispense charge as quickly as a starter battery but can also be used to start combustion engines. You would simply need a bigger deep-cycle battery than if you had used a dedicated starter-type battery instead. The thicker the lead plates, the longer the life span, all things being equal. Battery weight is a simple indicator for the thickness of the lead plates used in a battery. The heavier a battery for given group size, the thicker the plates, and the better the battery will tolerate deep discharges.

Some “Marine” batteries are sold as dual-purpose batteries for starter and deep cycle applications. However, the thin plates required for starting purposes inherently compromise deep-cycle performance. Thus, such batteries should not be cycled deeply and should be avoided for deep-cycle applications unless space/weight constraints dictate otherwise.

Question 35

Regular versus valve-regulated lead acid (VRLA) batteries

Accepted Answer

Battery Containers come in several different configurations. Flooded Batteries can be either the sealed or open variety.
Sealed Flooded Cells are frequently found as starter batteries in cars. Their electrolyte cannot be replenished. When enough electrolyte has evaporated due to charging, age, or just ambient heat, the battery has to be replaced.
Deep-Cycle Flooded cells usually have removable caps that allow you to replace any electrolyte that has evaporated over time. Take care not to contaminate the electrolyte – wipe the exterior container while rinsing the towel frequently.
VRLA batteries remain under the constant pressure of 1-4 psi. This pressure helps the recombination process under which 99+% of the Hydrogen and Oxygen generated during charging are turned back into the water. The two most common VRLA batteries used today are the Gel and Absorbed Glass Mat (AGM) variety.
Gel batteries feature an electrolyte that has been immobilized using a gelling agent like fumed silica.
AGM batteries feature thin fiberglass felt that holds the electrolyte in a place like a sponge.
Neither AGM nor Gel cells will leak if inverted, pierced, etc. and will continue to operate even under water.

Question 36

What is servo voltage stabilizer?

Accepted Answer

Servo Voltage Stabilizer uses an advanced electronic controlled servo motor concept to govern a motorized variable transformer. Because of the motors involved, there is a small delay in voltage correction. However, output voltage accuracy is usually ±1% with input voltage changes of up to ±50%. This type of technology tends to be extremely effective when considering large three-phase applications, as it is able to maintain its accuracy of all these phases, despite of input voltages balance and load balance at any power factor.

Question 37

What is the need of servo voltage stabilizer?

Accepted Answer

Highly fluctuation in AC supply is a common phenomenon in the whole country. The voltage requirement of different electrical appliances varies to a great extent. The electronics equipment like spectrophotometers, PH-Meter, X-Ray plant, recorders is all affected by high main voltage, whereas the refrigerators, deep freezers, incubators, and other compressors are affected by low main voltage. However industries, which are running 24 hours, also affected by this fluctuation of voltage. So, to achieve constant voltage Servo Stabilizers are used.

Question 38

How to select servo voltage stabilizer?

Accepted Answer

When you select any stabilizer, it requires some data as follows:
- Input Voltage range
- Output Voltage range
- KVA rating.
- Type of load: balance/unbalance.
- Type of voltage: balance / unbalance.
- Type of protection required.
- Type of cooling: air/oil

Question 39

What is the main function of the stabilizer?

Accepted Answer

The main function of the Stabilizer is to stabilize the voltage & safeguard the electrical equipment. Energy saving is an added advantage.

Question 40

Which protection to use in your stabilizer?

Accepted Answer

We provide protection against short circuit, overload, over-voltage/under-voltage, and also if customers have any specific requirement.

Question 41

What is the efficiency of your stabilizer?

Accepted Answer

The efficiency of our Stabilizer is more than 97% in comparison with other types available in the market.

Question 42

How will i select stabilizer rating for my home / office?

Accepted Answer

Before selecting the stabilizer you need to know how much power you use. By taking an inventory of all the essential electrical loads in your house/office, and doing a basic electrical load evaluation, you can get a good idea of how much power your system needs to produce. Second, you have to know about the power Fluctuation situations also that means what voltage minimum/maximum you are getting from the main A.C. supply. In brief, you have to select the Input Voltage window and the power consumption of your appliance.

Question 43

What is transformer?

Accepted Answer

A transformer is an electrical apparatus designed to convert alternating current from one voltage to another. It can be designed to "step up" or "step down" voltages.

Question 44

Is it possible to change three phase to two-phase vice versa with standard transformer?

Accepted Answer

Yes. This is a very practical application for standard single-phase off-the-shelf transformers. Some typical voltage combinations are as follows: 480 volts three-phase to 240 volts two-phase, or 240 volts three-phase to 480 volts two-phase, or 240 volts three-phase to 240 volts two-phase. Please refer to us for an exact schematic.

Question 45

How does a transformer work?

Accepted Answer

A transformer works on the magnetic induction principle. It has no moving parts and is a completely static solid-state device, which insures, under normal operating conditions, a long and trouble-free life. It consists, in its simplest form, of two or more coils of insulated wire wound on a laminated steel core. When voltage is introduced to one coil, called the primary, it magnetizes the iron core. A voltage is induced in the other coil, called the secondary or output coil. The change of voltage (or voltage ratio) between the primary and secondary depends on the turns ratio of the two coils.

Question 46

What are taps and when are they used?

Accepted Answer

Taps are provided on some transformers on the high voltage winding to correct for high or low voltage conditions, and still deliver full rated output voltages at the secondary terminals. Standard tap arrangements are at two and one-half and five percent of the rated primary voltage for both high and low voltage conditions. For example, if the transformer has a 480volt primary and the available line voltage is running at 504 volts, the primary should be connected to the 5% tap above normal so that the secondary voltage be maintained at the proper rating.

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