Based in Durbanville, servicing the Cape Town areas.
Inverter Systems, Supply and Installation by Qualified Electricians.
Eskom load shedding often leaves us in the dark at very inconvenient times, if it happens during the day business production is affected costing business owners money, after hours cuts negatively impact on our home lives.
An standby inverter system offers silent and virtually instantaneous power backup in the event of power failures.
Remember, an inverter system should only be installed by a qualified electrician, incorrect installation can be dangerous.
The Techno Group provides an inverter solution to fit your needs and budget from a basic system to power some lights and a few appliances to a fully automatic system that powers the entire home or office, charged by mains or Solar.
The Techno Group will assess your standby power needs and advise you on the size and type of inverter installation you require, beware…not all inverter systems are the same, see the below points to consider when installing an inverter.
Pure Sine Wave Form.
Electricity. How does it work?
In order to understand the differences between various inverters let’s take a look at how electricity, specifically Alternating Current, AC, works.
To the left is an image of what the electricity we receive from Eskom should look like, it’s a nice smooth wave form, rising smoothly from zero to a peak and smoothly dropping to zero again before reversing direction and repeating the process, this complete cycle repeats itself 50 times a second known as the Frequency, 50Hz.
This smooth waveform is the result of the Eskom generators running at a constant speed of around 1500rpm designed to supply 230Vac at 50Hz.
Square Wave Form.
How does an inverter work?
Unlike a generator that naturally produces a sine wave form an Inverter works by utilising stored, or supplied, Direct Current, DC, that it then converts to a form of Alternating Current, AC.
Different inverters do this by various methods, ranging from producing a poor quality square wave form to the better quality pure sine wave form, others produce something in between these two called a Modified Sine Wave.
Direct Current is what a battery supplies, it provides a steady constant voltage that flows in one direction only, unlike AC it does not reverse direction 50 times a second nor does it vary in voltage. An inverter has to utilise this direct current and convert it to a reversing current.
Not only does an inverter need to generate some sort of alternating current, but it also needs to step up the supplied DC voltage from the common 12Vdc to 230Vac.
Different inverters achieve this conversion with varying degrees of accuracy depending on how many processing steps are involved.
The cheaper inverters output a Square Wave Form simply by stepping up the voltage and physically switching polarity 50 times a second, thereby generating a rather crude form of Alternating Current, these devices are not very popular owing to the fact that many appliances will simply not work on this supply, especially electronic devices.
Modified Sine Wave inverters offer a better quality output by adding a few more processing steps to generate a multi step square wave output, most appliances will work with these inverters, but certain loads, especially motors may suffer diminished efficiency and can generate some noise.
Pure Sine Wave inverters are naturally the most expensive, but achieve a pure sine wave output by utilising high speed switching circuitry combined with smoothing circuits.
Although a Pure Sine Wave inverter is the best solution your load requirements may not necessitate it, a Modified Sine Waver inverter may be good enough for your needs, especially if you are not powering motors or electronic devices.
Points to consider when investing in a standby power inverter system.
Assess the load, will you be powering your entire home or office or just lighting and certain vital appliances, reduce your load by converting to energy saving lighting/appliances where possible, this will decrease the demand on the system.
An inverter system works by storing a certain maximum amount of energy in a battery bank, normally determined by an Ampere Hour rating, once you have determined the size of the load you require powered you also need to decide how long a period you may require standby power for, once the stored energy in the system is consumed it will require a re-charge, either from mains supply or a solar system. (Operating time is determined by dividing the system capacity by the potential load).
Inverters not only have a Load Rating in terms of the amount of power it can provide on a constant basis, but it’s vital to check it’s peak output ability too, different appliances require variable amounts of power at different times.
A motor may draw in excess of 10 times it’s full load current for a second or two on start up, many appliances in our homes contain motors or compressors. Your inverter will need to be able to handle these peaks as well as the full running demands.
Do you have a suitable place in your home or office where the system can be safely installed, requires ventilation and protection from moisture.
What type of load will you be powering, this will determine the quality of power supply required, some appliances, especially electronic devices, require good quality 230Vac, 50Hz pure sine wave. An inferior standby supply system could result in certain appliances not working or possibly even damage them.
Certain fluorescent and compact fluorescent lighting may not operate properly on Modified Sine Wave inverters, we currently have no data on LED lightings compatibility with Modified Sine Wave.
Modified Sine Wave inverters may cause interference with Audio Video equipment.
Devices with internal clocks or timers may not operate properly on Modified Sine Wave.
It is possible to install a Pure Sine Wave inverter for critical circuits that require a good quality supply and a Modified Sine Wave inverter for less critical circuits, this will save you on the cost of a larger Pure Sine Wave inverter.