Dealing with overvoltage
Overvoltage from the electricity network can have a detrimental impact on the performance of AV equipment. Kevin Main from Torus Power explains.
Do your clients often struggle with exceptionally high energy bills? Frequent burnt out light globes? Blown fuses? For several years now, Australia’s electric grid has experienced voltage regulation problems, most notably, overvoltage.
For the home technology professional, as well as the end user, a fluctuating power grid can lead to big problems, severely damaging sensitive electronics, shortening the lifespan of sophisticated smart home components, and even diminishing the AV quality of home entertainment systems. Even if you’ve charged top dollar to design and install a home theatre and smart home system, if you didn’t install the proper power protection, overvoltage can ruin your client’s technology experience.
Of course, the more technology you have in a home, the greater the damage will be, which means that residents in today’s luxury smart homes will suffer from the effects of overvoltage.
Behind the Struggles of Australia’s Electric Grid Today
Have you ever heard the phrase, “Drinking from a firehose?” In today’s era of big data and the internet, it usually means trying to absorb too much information at one time. The quantity is too overwhelming. A similar analogy could describe the power grid across Australia. Homes and businesses are receiving more electricity than they need, and the grid wasn’t designed to regulate voltage delivery to the sensitive electronic components that are often found in home technology projects.
Ironically, overvoltage issues are caused by a burgeoning energy crisis. With the closing of ageing coal plants, there is a real concern about running out of energy during peak usage times such as hot summer days. The solution, at a glance, would seem to be renewable energy, especially solar and wind power. But aside from the issue of intermittency, Australia’s century-old electric grid was not designed to transmit energy through sensitive inverters connected to wind farms and solar arrays. In practical terms, and to compensate for peak energy demands, the supply voltage is often increased so that it can deliver the full demand at these peak demand times.
The consequence? Overvoltage, which causes headaches for home owners, especially those who live in smart homes and demand the best performance from their AV and home automation equipment.
In home technology systems, overvoltage causes electronic equipment to operate at higher-than-normal temperatures, which shortens the lifespan of sensitive electronics. This condition stresses the power supplies of AV equipment and leads to burnt PCBs, and microprocessors, and failed power supplies.
The Importance of Voltage Regulation
The electric grid delivers power within an allowable range of 216V to 253V. The nominal voltage in Australia, however, is 240V. The closer you can stay to this nominal voltage, the better for the life and performance of your gear. Unfortunately, in most Australian states, electricity is delivered with voltage closer to the high end of the range and, quite frequently, above the 253V acceptable level. Fortunately, with the right equipment and a professional integrator to assist with system design, you can overcome overvoltage problems and stabilize the electric supply coming into your house at a steady output of 240V +/-10V.
To counter the effects of overvoltage and mitigate the noise and artifacts that are present, you’ll want to isolate the equipment from the problems on the grid and then regulate the voltage going into the electronic components. Ideally, all the electric loads within your home should be divided into categories and isolated from each other. The electronic devices in today’s homes fall into three categories:
- Motor loads, such as refrigeration and air conditioning, which are necessary for daily living but don’t necessarily require consistent power for optimal operation.
- Lighting and appliances, such as dimming circuits, microwaves, toasters, etc.
- Sensitive electronic loads, including AV equipment and control systems, which require stable, clean and consistent power for optimal performance.
While overvoltage may result in blown fuses or light globes across your home, the third category of electronics is most susceptible to the effects of overvoltage and inconsistent or ‘dirty’ power.
Isolating Power Helps Protect Audio, Video and Control Systems and Improve Performance
Fortunately, there is a solution to the overvoltage issue – and it doesn’t start with the grid but, rather, in the home. Home technology specialists often rely on toroidal isolation transformers specially designed for AV applications to completely isolate primary and secondary loads, provide a clean power supply and attenuate power line noise.
To protect expensive equipment and improve audio, video and control system performance, you must first isolate the power going to sensitive loads. The low impedance results in instantaneous and consistent power, with less noise and interference. Video systems will have improved image fidelity, truer colours, whiter whites and blacker blacks. Audio systems will benefit from a cleaner soundstage with a lower noise floor, better dynamics, imaging and bass. High-resolution audio formats, especially, will benefit from the improved audio quality, although you may hear a noticeable improvement in nearly any system. Most importantly, artifacts and harmonics on the voltage supply that cause ongoing reliability issues for sophisticated modern home technology systems are eliminated.
Voltage Regulation Provides a Clean, Stable Output
In addition to power isolation, voltage regulation plays a key role in AV system protection and performance. Isolation transformers with Automatic Voltage Regulation can accept power ranging from 190V to 270V, providing a clean, stable output of 240V +/-10.
You can use a full online UPS system, giving the inverter/regenerator design a battery backup to deliver pure sine wave output even if utility power is lost. Although battery backup is important for components with microprocessors, it shouldn’t be the only method of voltage regulation within a sophisticated, delicate smart home system. Multi-tapped isolation transformers are designed to monitor and control the output voltage, seamlessly regulating power delivery. In other words, to revert to our original analogy, they can convert the firehose-style flood of electricity into a steady stream.
Power and Protect Your Home Technology Systems Like a Professiona
Recording and post-production studios have relied on power isolation and voltage regulation technology to segregate sensitive electronic loads for decades to protect expensive pro audio gear and deliver the best audio quality possible.
Today’s smart home technology systems require the same treatment to ensure clean, stable power reaches critical components. If your client is passionate about the entertainment experience their home technology delivers, power isolation and voltage regulation should be part of your system. Likewise, architects, builders and general contractors should be sure to leave room in the home technology budget for the proper power isolation components. From the moment the system is powered up and a movie or song begins to play, the performance improvement will be clear.