When it comes to electrical equipment, it is important to understand the potential harmful effects of high supply voltages. while a suitable supply voltage is essential to the proper functioning of any electrical device, it can also cause a great deal of damage if it is not managed properly.
This blog post will discuss the dangers of high supply voltages and how they can adversely affect your electrical equipment.
Traditionally in the UK we have talked about our voltage being 240V, in fact, our declared voltage is actually 230V +10% or -6% therefore anywhere between 216.2V and 253V. It is often assumed that is voltage is static when in fact this is not the case. If we monitor our supply voltage across the course the day we can see that it fluctuates. The screenshot below is from our offices in Glasgow and shows that the voltage is relatively stable overnight but varies significantly during the day when the local businesses and offices are occupied and in use, returning to a relatively stable state out with normal working hours.
High supply voltages, also known as overvoltage, are dangerous because they can over stress components. This can lead to overheating of the components, which can damage the device or even cause it to fail. Additionally, overvoltage can cause severe damage to the insulation of the electrical components, leading to shorts and sparking. This can also lead to fire hazards if the insulation is not properly maintained.
The screenshot below shows the supply voltage of our office in January of 2019 when we were experiencing a period of sustained high supply voltages. This had gone unnoticed for a considerable amount of time and when challenged our electricity supply company admitted that this was caused by a fault at their primary sub station and was therefore effecting 20,000 customers in the east end of Glasgow.
This fault was eventually fixed on the bank holiday the following May as is confirmed by the voltage trace below.
It is important to note that high supply voltages are not caused by poor installation and maintenance practices, rather they are the consequence of your local electricity supply network, transformer settings and the way in which your local electricity supplier is operating your local grid. As the prevalence of imbedded generation such as CHP systems , PV installations and wind turbines increases so does the likely hood of high supply voltages. it therefore becomes more important monitor your supply voltage and other power quality parameters in order to protect your electrical equipment from the dangers of high supply voltages.
While surge protection devices (SPDs) are available these are designed to protect equipment from large spikes such as those caused by lightning strikes and such have limited benefit in protecting against over voltage.
Additionally, it is important to regularly inspect your electrical equipment for any signs of damage, overheating or wear and tear.
Finally, it is important to be aware of the environmental conditions in which your electrical equipment is being used. Extreme temperatures and humidity can have a negative effect on the performance of your equipment, so it is important to make sure that the environment is suitable for the devices.
In conclusion, high supply voltages can have a detrimental effect on your electrical equipment and consequently there are huge benefits in the continuous monitoring of your power quality parameters.