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T he Volt-Ampere (VA) is a unit of measurement for power that a device uses in terms of voltage (V) and amps (A). Consider water running in a pipe: Voltage is to water pressure, as current is to the flow of water. Together, VA determines the total power consumption of a device. This is the amount of power it takes to illuminate the bulb and the amount of power used to electrify the circuit (wasted power). So ideally the lower the VA rating the more efficient the circuit. With a lower VA rating, your system can use a smaller transformer to drive the same number of more efficient lights on a circuit.

The longer explanation:

The Volt Ampere (VA) system is a method of measuring the power consumption of electrical components, such as LED lights among other devices. It’s pretty important to have a basic understanding of this system when choosing and installing LED lighting, as it can affect the overall energy efficiency and performance of the lighting installation.

VA can be identified in two ways, by either the formula V x I = VA where Voltage x Current equals Volt-Amperes. Or, if you know what the power factor of the lamp is, it can also be determined by W/PF = VA where you take the Wattage of the bulb and divide by the Power Factor (PF) to get the Volt-Ampere.

The VA system measures the power consumption of a device in terms of voltage (V) and current (A). Think of voltage as the electrical pressure that pushes the current through the device, while the current is the flow of electrical energy. Together, they determine the total power consumption of a device.

A multimeter is a device used to measure electric current, voltage, and usually resistance, typically over several ranges of value.

When it comes to LED lighting, the VA system can be used to identify the power consumption of different types of lights. As an example, a 6W LED light with a voltage of 12V will have a current of 0.5A, while a 6W LED light with a voltage of 24V will have a current of 0.25A. The power consumption in both cases is 6VA, but the current is different.

It is important to note that the power consumption of LED lights is not always the same as their power rating. This is because LED lights are often operated at a lower voltage than traditional incandescent lights, which can lower their total power consumption. Additionally, the VA rating of LED lights can vary depending on the type of driver and dimming system used.

When choosing LED lighting, it is important to consider the power consumption of the lights in terms of VA. This will help ensure that the lights are energy efficient and operate at an optimal performance level. Not all LED bulbs are created equal, some bulb drivers use more energy than others outside of the required amount to produce light. This is why it is also important to choose LED lights with high-quality drivers and dimming systems to further increase their efficiency. In general, the lower the VA rating of the lamp the better, as there is less wasted energy in the circuit dedicated to producing light. This knowledge will allow for a better understanding of the type of transformer needed for any given number of bulbs on a circuit and give you a solid idea of what you can expect if you decide to add more lamps to a circuit at a later time.

V * I = VA


This short video provided by LetZgo is an excellent real-world example of what efficient products can get you. Matt Utley demonstrates how high-efficiency bulbs with a low VA rating, paired with a high-quality dimmer can make all the difference and increase your overall output of light with the same transformer!

In Summary:

The Volt Ampere (VA) system is an important method of measuring the power consumption of electrical devices, and in our case, LED lights. Understanding the VA system and how it relates to LED lighting can help ensure that you choose and install lights that are energy efficient and operate at their optimal performance level. If you have any questions or would like us to help you make a choice based on your needs, please feel free to reach out to us. We’d be happy to help!