How do you check phase sequence?

It's outside the scope of this answer to go into the theory, but a 3 phase motor by convention normally rotates anticlockwise when viewed from the 'driven' end.

To check phase sequence, the usual method is to use a phase sequence indicator. Originally these were like a miniature three phase motor encased in a hand-held device. If the flying leads were connected RYB, BRY, or YBR, the disc in the psi would rotate anticlockwise. If the flying leads were connected RBY, BYR, or YRB the disc would rotate clockwise. Nowadays, the mechanical aspect of the phase sequence indicator has been repalced with solid state devices that indicate on one of two leds if the sequence is c/w or ac/w.

To check phase sequence you look for which phase out of the three phases peaks first. You could probably put each phase on an oscilloscope and see which one peaks first. Phase sequence is usually taken as positive anticlockwise from the reference voltage ( the phase that peaks the first).
+ 6 others found this useful
Thanks for the feedback!

What's the craziest/most daring thing you've ever done when traveling?

View Full Interview

What is relation between power factor and phase sequence?

The power factor of an AC electric power system is defined as the ratio of the real power flowing to the load to the apparent power,[1][2] and is a number between 0 and 1 (fre (MORE)

How negative phase sequence occoures?

If electrical systems were all balanced the expression negative-sequence would never be needed! Fortunately, the solution for balanced systems is to convert all parameters to (MORE)

What is the importance of phase sequence?

The importance of phase sequence is related to the direction of rotation for a motor.   The three phases set up a rotating magnetic field, which runs the motor. Reverse (MORE)

What the use of phase sequence indicator?

In indicator there is a led light source. It gives us the presence of the current source by indicate its light. If the phase of the indicator is not equal to the supply voltag (MORE)

Popular Forms of Yoga Sequences

Yoga is a mind-body exercise that connects breathing to movement and meditation. All yoga practices revolve around poses, also known as asanas, and the mindful movement from o (MORE)

8 Yoga Sequences to Meet Your Health Needs

Whether you want to boost your metabolism or enjoy some rest and relaxation, using targeted yoga sequences is a great way to meet your health needs. While some sequences have (MORE)
In Signs

Migraine is More Than Just a Headache

Migraine is more than just head pain. Migraine consists of symptoms occurring before head pain, unpleasant symptoms occurring during the time of head pain, and symptoms after (MORE)
In Poses

Yoga Sequence for Depression

Depression is a condition that can easily extend into all areas of your life. As such, finding a way to combat it is essential. While there are many medical treatments out the (MORE)

How check polarity of three phase transformer?

You don't. 'Polarity' applies to single-phase transformers, and knowledge of polarity is an essential requirement before you can connect three single-phase transformers to for (MORE)

How can find out the terminal sequence of a three phase induction motor?

If you are concern about the rotation of the 3 phase motor, all you have to do is connect the power to the three terminal wires, make sure connections are tight, insulate one (MORE)