What is the Difference Between Square Wave and Pure Sine Wave Inverters?

What is the Difference Between Square Wave and Pure Sine Wave Inverters?

“Do you want get a Sine Wave Inverter or Square Wave Inverter?”

Perhaps, this is one of the most common questions you’ll get when you try to purchase a power inverter. So what’s an inverter anyway? The majority of household electrical appliances use an Alternating Current (AC) electricity. On the other hand, a battery stores Direct Current (DC) electricity. The main purpose of an inverter is to convert the DC electricity into AC electricity.

But when it comes to the basis of its circuits, an inverter converts DC current to either Square wave AC current or Sine wave AC current. The Sine wave inverter output is very similar to the AC current. In comparison with the Square wave output, the Sine wave output is purer; that’s also the reason why the term Pure Sine wave inverter exists.

To give you an idea of how the two currents look like, refer to the photo below:

One more important thing that you need to know is many household devices get heated up if you’ll use Square wave inverters. This is the reason why Square wave inverters are banned in some European countries. Other than that, we outlined a comparison chart between Sine wave inverters and Square wave inverters below to help you differentiate them better.

Comparison Chart: Square Wave Inverter vs. Sine Wave Inverter

List of Features Square Wave Inverter Sine Wave Inverter


Supported Appliances


Square wave inverters are usually used to support motors alone.

Sine wave inverters are used to support household appliances such as refrigerators ovens, computers, laptops, etc.

Overall Safety Level

Square wave inverters are less reliable and also unsafe to use for appliances. Sine inverters are highly safe to use.

Noise Interference

Square wave inverters produce a very loud noise when used. Sine wave inverters produce normal sound only.


Square wave inverters are less expensive than Sine wave inverters. Sine wave inverters are more expensive than Square wave inverters.

Furthermore, there’s another type of inverter that you can take advantage of. This one is called “Modified Sine Wave Inverter.” This type of inverter is better than the Square wave inverter and more affordable than the Sine wave inverter. A Modified Sine Converter can be utilized for simple systems, however, there are heaps of equipment that it cannot support. Some of these are the following:

  • Medical equipment (e.g. oxygen concentrators).
  • Some laptop computers.
  • Home Automation Systems.
  • Anything that has Silicon-controlled Rectifier (SCR).
  • Laser Printers.
  • Photocopiers.
  • Appliances with microprocessor controls.

If you are planning to purchase a Modified Sine wave inverter, it is highly recommended to go for the Sine wave inverter instead. As modern technology continues to rise, the cost of pure sine wave inverters is dramatically decreasing, making them more affordable and accessible in the global market.

Are you needing of a UPS and an inverter to support your appliances? At PSS Distributors, we are offering high-quality equipment and installation services for our clients.

For sizing and costing, please visit our UPS calculator to see the best UPS for your personal needs at  http://www.pssdistributors.com.au/ups-calculator.

Why PSS Distributors?

To ensure you are choosing the right partnership for your next UPS project – you want a company that has proven themselves time and again and one who has previous experience with similar jobs, superior technical expertise and can offer the after sales support that you require.

So, Why PSS Distributors…

PSS Distributors has manufactured our own units since 1994, We have over 100 000 units in the market at present in 2 continents. Our technical expertise to design and manufacture the more difficult solutions has held us in good stead for 25 years.

A few of our more recognisable sites include:

  1. Toshiba CAT scans nation wide
  2. Avis Car Hire (2 x 60KVA)
  3. DHL (1 x 80KVA)
  4. BOC gases (1x 80KVA)
  5. Bunnings Warehouse (2000 x 600VA )
  6. NSW health
  7. Bosch
  8. Abbott Labs

We have designed and manufactured security power supply systems and have become the largest security power supply distributor in Australia, which include:

  1. Wall mount 4-24A in 12 and 24VDC
  2. Wall mount 4-25A in 24VAC
  3. Rack mount in DC and AC
  4. Battery backed up units

With over 40 years experience in power, innovative engineers, we have achieved what other UPS companies have turned away from, for example:

  1. Controlling a UPS to run on static switch to overcome large inrush currents and transferring back to inverter remotely when given the signal (CAT scans)
  2. Designing UPS with sleep mode to operate weeks after a power failure when needed (roller shutter doors)
  3. Manufacturing cost effective UPS systems with small inverters but large charges for very long battery back up (security cameras / telecommunications)
  4. Arranging UPS systems that convert single phase to 3 phase (lathes, power tools in workshops etc)
  5. Dedicated UPS systems to keep pumps on vaccine fridges running for hours.

How Long Does a UPS Battery Last For? 

How Long Does a UPS Battery Last For? 

“Well, how long is a piece of string?”

This is probably one of the most frequently asked questions by customers who are planning to purchase an Uninterruptible Power Supply (UPS). While it is understandable for consumers to be concerned about the capacity of their power source, determining the exact life span of a UPS battery is pretty hard to do.

Unlike the typical alkaline batteries, the life a UPS battery depends on a number of impacting factors such as environmental conditions, maintenance, and the number of discharge cycles. However, the standard capacity of a UPS battery is three to five years, depending on the factors that may affect the performance of the UPS.

All UPS manufacturers never fail to remind their consumers that the UPS battery is the most vulnerable part of the entire system. Thus, learning how to manage and maintain your UPS batteries properly will extend their overall capacity and will also help you save time and trouble in the future.

When it comes to environmental conditions, there is a set of standards that need to be met to get the maximum life out of your battery. We have listed some of these factors:

  1. Room Temperature

It is essential to recognise that ambient temperature can alter the performance of a UPS battery and can potentially shorten its expected life span. The optimum temperature to store a UPS in is  21°C – 25°C. The maximum temperature to store a UPS in is 50°C, however when the temperature increases or decreases from the optimum range, this is when it begins to affect the life span of a battery.

PSS Distributors sell a range of 19”racking systems, as well as fans and aircons to help keep critical equipment and UPS at their desired temperature.

  1. Regular Maintenance

No matter how well-kept your batteries are, they still need to undergo proper maintenance. Neglecting to do such safety measure may cause your UPS batteries to experience improper loading, heat-generating resistance at the terminals, loose connections, premature failure, and reduced protection. Some UPS models require extensive maintenance since regular checkups are critical to their overall reliability.

  1. Cycling

During a power outage, UPS operates using its own battery power. Once that power has been fully restored, the battery will then get recharged for future use. This process is called a discharge cycle. When the UPS was first installed, the battery’s rated capacity is at a hundred percent. However, each discharge cycle reduces the relative capacity of the battery by a small percentage.

  1. Battery Chemistry

Unfortunately, UPS batteries are electrochemical devices and are not designed to last a lifetime. Even if your UPS batteries are well-maintained and meet the specific standards for proper storage, your batteries will still run out of power, and you will be required to do a replacement after a particular period of time.

Overall, even though UPS batteries don’t last forever, following the guidelines that we have provided above, you will surely be able to maximise your UPS life span.

If you’re currently planning to replace your UPS batteries with new ones, we can service and maintain a wide range of UPS, we are now fully staffed nationwide;


Why Do You Need A UPS for Your CCTV Cameras

Why Do You Need An Uninterruptible Power Supply (UPS) For Your CCTV Cameras

In the present day, numerous homes and businesses are investing in CCTV cameras for protection and security. As we may know, installing a CCTV camera is an excellent way to maintain the overall safety of a home or a business establishment’s perimeters. CCTV cameras are also beneficial when it comes to monitoring your premises when you’re away. 

UPS and CCTV Cameras

Since CCTV cameras need a constant supply of power to function efficiently, installing an Uninterruptible Power Supply (UPS) is an integral factor to consider. A UPS can provide a consistent amount of power to the CCTV system, especially in the event of an unexpected power outage.

Moreover, there are other benefits that UPS can provide for your security cameras, such as:

  • Automatic Voltage regulator
  • Surge protection
  • Option to notify you if the power has been cut (added security)
  • Continuous and uninterrupted monitoring

If you’re looking forward to installing one, PSS Distributors can take care of your UPS installation. We guarantee that no matter how small or big the installation is, we will provide each project with proper planning, professional technology, and relevant skills to ensure reliable power protection.

For sizing and costing please visit our UPS calculator to see the best UPS for your security needs- http://www.pssdistributors.com.au/ups-calculator/



The Thor DRM95!!

Imagine having prefect sound and vision, well now you can!


… The Thor DRM95!!

The Thor DRM95 is the only product in its class with Thor’s Patented dynamic active tracking.

But what does this all mean:

Do your lights flicker, does your TV sometimes look blurry or is the colour not as sharp as it should be. AC power coming into your property is not always as ‘clean’ as we expect. There will often be power spikes or surges that will not only affect the day to day running of your electrical appliances and equipment yet may damage them.


  • Dynamic Active Tracking Double Filtration
  • Internal Back EMF Protected
  • High Temp and High Impact Housing
  • EMI/RFI Noise Reduction filter
  • Easy to install
  • Single Phase Device
  • Three Phase Application (one each phase)
  • Din Rail Mounted
  • 20Amp and 30Amp models

So how does The Thor DRM95 help in this protection:

The Thor DRM95 is an AC mains Dynamic active tracking filter that also has a built-in surge protection isolator.

What is a spike?

A Spike is a rapid increase in voltage that lasts less than a millisecond.

Spikes- degrade components and shorten the components life.

What is a surge?

A surge is a rapid increase in voltage that lasts longer than a millisecond

Surges last longer and tend to cook or burn out equipment

High and Low power problems

Blackouts, brownouts and why you need surge protector for both!

What is Active tracking?

Active tracking filters up to 40% more frequencies, as apposed to competing products that are passive tracking.

We spend thousands of dollars on expensive equipment yet if the AC power to the building is not monitored and corrected we risk these products functioning improperly or getting damaged.

With more reliance on electricity in the average commercial and residential property doesn’t it make sense to protect your equipment?

Contact us for more details and pricing!

PSS Distributors is now Distributing this Thor product.

Congratulations Team PSS

PSS has been selected as a Small Business Champion Finalist from over 2,000 entries received this year.

This achievement is a testament to the vision, planning and hard work invested in this business to deliver spectacular results. Congratulations Team PSS.


Discarded electronic equipment is one of the fastest growing waste products today due to the increasingly large usage of these products. This needs to be monitored responsibly and methods used such as effective collection, reuse and recycling. Each person using these products can also make the right and responsible decision for discarding their equipment.

Electronic equipment waste contains hazardous material which is harmful to the environment and human health and this waste is growing three times faster than general municipal waste.

Governments and organisations are working closer with such projects.

At PSS – we take discarding of our old electronic items and batteries very seriously and ensure our methods comply with safety standards.

We strip out units and recycle the parts. We also offer a service to our customers whereby we discard their old batteries for them.

Please call us on 130088447 for assistance or information.

9RU wall mount rack

Due to the great success of the Redback Rack range of racks, we have now introduced a 9RU wall mount rack. This model comes in 450 mm deep as a single section and a 600mm deep as a double section. The double section has a convenient hinged back to make cable access to the rear of mounted equipment easy to install cables etc.