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About Ideal Phase Sequence Testing

Electricity is often sent from a generator to its destination along a phase sequence. In many of the world's industrialized nations, it employs a sequence of three phases. And in order to make sure that any phase sequence is running smoothly and that there's no danger to any equipment -- let alone any people -- it's necessary to test a phase sequence from time to time.

Phase Sequences
- In electricity, a phase sequence, also called a polyphase sequence, involves a generator taking in mechanical energy and converting it into electrical energy. Electrical currents that a generator creates are sent out in phases, usually three phases represented by the colors red, blue and yellow. The electricity that emerges from these generators can range from hundreds to thousands of volts. When that electricity reaches the object or building that it's intended to power, it will pass through a series of conductors on its way into the correct circuits. Once all that electrical energy has been used up, the phases will return to the generator.
A Proper Sequence
- A three-phase electrical sequence involves three conductors, all active, as well as an earth ground and a series of motors. In order for these motors to work correctly, however, the electrical sequence must meet certain conditions. That is, there must be between 208 volts and 415 volts of power coursing between any two of the phases at all times, and 120 volts to 240 volts between each phase and the earth ground. To ensure that you have the correct voltage all along the sequence, you must be able to test the sequence.
Testing a Sequence
- It's important to test phase sequences because if any motor along the sequence isn't hooked up properly, equipment can be damaged, especially if a motor is hooked up so as to cause reverse rotation. A motor rotation testing device can help ensure that reverse rotation doesn't happen. When shopping for such a device, choose one with plenty of battery life and one that's easy to use and read. Other testing instruments can indicate whether or not voltage loss has occurred within a phase sequence.
Saving Money and Staying Safe
- If you want a less expensive way of testing the rotation of a motor, you can set up neon lights beside each of a phase sequence's motors. These neon lights make the path of each motor visible, so you can be sure each of these motors is turning in the right direction. No matter how you test a phase sequence, however, it's critical for safety's sake that you know exactly what you're doing each step of the way. If you're unclear about something, get someone else to do your testing.

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