Understanding Transformer Nameplates: What You Need to Know

A transformer rated 25 kVA and larger must have a nameplate showing which of the following?

• A. Manufacturer's name and rated kVA
• B. Frequency and impedance of the transformer
• C. Primary and secondary voltage
• D. All of the above

Answer: (D)

A transformer rated at 25 kVA or larger is required to have a nameplate that displays essential information, which is crucial for safe and proper operation. The nameplate serves as a comprehensive guide for users and installers about the transformer's specifications and operational limits. Having the manufacturer's name and rated kVA is essential as it provides information about the producer of the transformer and the capacity it is designed to handle. This helps ensure that the transformer is appropriate for the intended application. The frequency and impedance specifications are also critical. The frequency indicates the rate at which the transformer is designed to operate, which directly affects its performance and compatibility with the power system. Impedance is vital for understanding how the transformer will behave under load, especially regarding voltage drop and fault current levels. Lastly, including both primary and secondary voltage is important. This information allows users to understand the voltage levels the transformer is designed to work with, ensuring that it matches the source and load requirements effectively. In summary, all of these elements—manufacturer's name and rated kVA, frequency and impedance, and primary and secondary voltage—are crucial for the safe and correct operation of a transformer of this size, which is why a transformer of 25 kVA or larger must exhibit all of the listed

When you're gearing up for your HOLT Electricians Exam, understanding the nitty-gritty of transformer nameplates is a must! Let's face it, the nameplate of a transformer—a seemingly simple label—holds a treasure trove of information vital for safe operation. So, what should you look out for, especially when talking about transformers rated at 25 kVA and larger?

You see, a transformer rated at 25 kVA or more is mandated by electrical codes to flaunt certain information right upfront on its nameplate. Think of it like a car's specification sheet—it tells you everything you need to know before you hit the road. But in this case, it's about ensuring your electrical system runs smoothly and safely!

First off, the manufacturer's name and the rated kVA should definitely catch your eye. Why's that important? Well, it helps you identify the producer of the transformer and understand its capacity. This is essential because you want to ensure that the transformer fits your specific needs. You wouldn't want to pull a muscle trying to lift something too heavy, right? The same goes for transformers; picking one that matches your load is crucial.

Now, let’s chat a bit about frequency and impedance. The frequency will tell you how fast the transformer is designed to operate, which is fundamental for its performance. Imagine prepping a dish; everything needs to blend well together—just like frequency and your power system! If they're mismatched, you could end up with sizzling problems, rather than electrical solutions.

And impedance? Oh, that’s where things get interesting! It’s all about understanding how the transformer behaves under load. Think of it like understanding your friend's mood when they’re stressed; it gives you a sense of how things might play out during tough situations—like voltage drops or current faults in this case. Knowing this helps in anticipating problems and ensuring your transformer holds up under pressure.

Lastly, the primary and secondary voltage figures are your GPS in this entire transformer journey. They clarify what voltage levels the transformer is designed to handle, ensuring it works well with both the source and the load. You wouldn't want to connect a 110V appliance to a 220V circuit, right? It’s a recipe for disaster!

In essence, the nameplate provides a roadmap to the transformer’s capabilities—like a blueprint for success. Having all this information—manufacturer's name and rated kVA, frequency and impedance, and primary and secondary voltage—on display isn’t just a technicality; it’s a safety necessity. So, remember, armed with this knowledge, you’ll be well-prepared to tackle the HOLT Electricians Exam and ensure that every transformer you encounter on your journey is respected for its specs!