Phase converters generate three-phase electricity from single-phase electricity and vice versa. They also power transmission systems to increase or decrease line voltages for long distances without using excessive amounts of copper wire. When a phase converter experiences a sudden increase in the load or overloads, the voltage can exceed its regular limit. Keep reading to learn more about why this voltage increase occurs and how to correct the problem.

What Happens When the Voltage Exceeds Its Capacity?

When the voltage increases suddenly, the rotary phase converter will shut down to avoid damaging the electrical system. The system cannot supply power when it’s shut down. This means any device connected to the electrical system will stop working until the phase converter resumes operation.

What Are Voltage Lines?

A rotary phase converter contains three wires, two of which are connected to the same voltage and a third which is connected to a separate voltage. The first two wires are called input lines, and the third wire is known as the output line.

These input and output lines—better known as voltage lines—convert alternating current (AC) into direct current (DC) and vice versa. They’re found at the end of a transmission line and help maintain a constant power supply by regulating voltage as it moves from one point to another.

Line-to-Line Voltage vs. Line-to-Ground Voltage

While line-to-line voltage and line-to-ground voltage share some similar features, they also have key differences. Take a look below to learn what those differences are:

Line-to-Line Voltage

Line-to-line voltage is the difference in voltage between separate transmission lines of a three-phase power supply. It measures the voltage drop across a resistor with no load.

Tips & Insights: What Are the Advantages Of Using Three-Phase Power?

Line-to-Ground Voltage

Line-to-ground voltage is the voltage supplied from the line to the ground. This voltage is generally measured in volts and measures how much electric potential exists between the two points. Unlike line-to-line voltage, line-to-ground voltage records the voltage drop across a resistor with a load.

Line-to-ground voltage can also be used to:

  • Determine whether an electrical grid is overloaded
  • Determine if a circuit breaker will trip

Why is the Voltage High On My Phase Converter?

If the voltage is high on your phase converter, you might be wondering why. Below you will find two potential causes for this voltage imbalance:

All Line-to-Line Voltages Are the Same

When all line-to-line voltages are the same on a phase converter, the voltage will increase and cause an imbalance. This imbalance occurs because the load isn’t shared equally among all three phases.

Line Three’s Line-to-Ground Voltage Is High

Line-to-ground voltage measures the difference in voltage between the line and the ground. When the line-to-ground voltage is high for line three, the phase converter’s voltage becomes imbalanced because more current flows through the circuit than what the system is used to.

How Rotary Phase Converters Can Have a Voltage Imbalance

High Leg Delta—which isn’t a voltage imbalance—occurs when the voltage measured from line three to ground is higher than the voltage measured from lines one and two to ground. When line three suddenly increases or decreases, a voltage imbalance has occurred.

How to Correct a Voltage Imbalance On a Rotary Phase Converter

If your rotary phase converter experiences a voltage imbalance due to either imbalance single-phase loads or an undersized rotary generator, here are ways you can correct the imbalance:

Imbalanced Single-Phase Loads

When one phase has a higher load than another phase, it causes a voltage imbalance. To correct the imbalance, you can do one of two things:

  • Disconnect the single-phase loads from the rotary phase converter and connect them to a single-phase power source.
  • Level out the single-phase loads among lines one, two, and three.

Tips & Insights: 5 Common Welding Techniques and Why You Need a Rotary Phase Converter

Undersized Rotary Generator

An undersized rotary generator slows down when hit with a large power load and creates a voltage imbalance. The simplest solution to this problem is to replace the undersized generator with a larger one. Another possible solution is to alter the undersized generator so it imitates the constant speed of a larger generator.

Why These Issues Matter

If the voltage on your rotary phase converter is too high, you can’t get jobs done like you need to. This voltage imbalance can cause various problems, such as:

  • Making the power system unstable
  • Decreasing the quality of power
  • Increasing power consumption, making standard jobs more expensive to complete
  • Causing the motor to overheat and shut down

When you notice the voltage of your phase converter getting too high, address the problem as soon as possible to avoid inconvenient system slowdowns and breakdowns.

Shop Our Collection Rotary Phase Converters

If you’re in the market for a high-quality, durable rotary phase converter, we have the equipment you require. We offer a large selection of innovative phase converters to meet the requirements of your unique application. We handle everything from design to development to manufacturing in-house. Our team can create customized rotary phase converters to fit every customers’ needs. You won’t find better prices than ours. Shop our collection of rotary phase converters to power your projects. In addition, we offer other types of equipment such as three phase transformers and electric motors. Give our team a call by phone at (866) 418-9060 to receive assistance finding a phase converter for your project.