Lighting Transformers, Electronic Transformer, Light Ballasts
If you are installing lighting that requires a constant current flow, you will likely need a current transformer. These devices measure the current coming into them and proportionally put out either an alternating voltage or alternating current to whatever is connected to them. This can prevent flickering that is often problematic with many lights and lighting systems. You also might need a current transformer to determine if there has been a power surge, a circuit overload, a ground fault or in order to keep current feedback at bay.
When you are looking for a current transformer, keep in mind that there are two different types. You might encounter a wound transformer. These will be tied directly into the conductor carrying the incoming, measured current. The wiring for this is a series circuit to ensure that the current is guaranteed to pass through the transformer. The other type of transformer often found is a donut, also called a toroidal. Unlike wounds, donut transformers are not wired directly to the conductor. Instead, they have a window in the center of them, creating a donut-like shape. This window is where the wire from the current conductor is fed through.
Trying to find the right current transformer for your needs can be confusing unless you are well versed in the technical specifications for your project. There are several different figures which you will need to know prior to making your final selections for your transformer. The current that is being measured is the incoming or primary current. This number is the total load that the transformer is capable of carrying. The output of the transformer is the secondary current. This is represented by a range of numbers. If you are looking at the amount of insulation the current transformer provides when it is attached to the source, you need to look for the insulation voltage. How close the performance of the transformer is in the measured current compared to the ideal value is the accuracy of the device. One of the most important numbers to look at is the burden. This will tell you how much current the transformer can handle and still operate at a safe level. It is found by taking the current and the voltage that is applied to the circuit and multiplying the two. This number will be measured in volt-amperes (VA), but you could also find the burden given in Watts. This is the same value as volt-amperes. The total wattage of all devices connected to the current transformer should never exceed the burden.
If you are still in the dark about how to install or select a current transformer, you should consult with a professional electrician or ask an expert for advice.And tagged in Transformers.