Video transcription 

Good day and welcome to this on-line training course.
In this video, we will examine timing principles as applied to circuit breakers.
This course was produced by Zensol Automation in collaboration with Hydro-Québec,

At the conclusion of this video, the participant will be able to recognize the acceptance criteria and perform all the connections required to do timing tests.

Locating cable connection points.
How to connect the contact cables for a standard test?
How to connect the contact cables for a detailed test?
How to choose a test method?
How to connect the command cables?

How to connect the contact cables for a standard test?
There are two test methods used:
The first method is the standard test.
Cable connections in this method for a circuit breaker with two contacts per pole are shown in this illustration.
The instrument’s common cable is connected to the common point of the breaker.
Then the red and blue cables are connected to the main and auxiliary contacts.

Performing this test produces a single timing curve for the contacts.
One can deduce the insertion time of the pre-insertion resistor.
However, this test does not show the overlap time of the main and pre-insertion

How to connect the contact cables for a detailed test?
The second method used is the detailed test.
Before connecting the cables, it is necessary to electrically separate the auxiliary contact from the main contact. This is done by removing the jumper that connects these two contacts.
Cable connections are then made as shown in this slide.
Note that two cables are required to completely connect a T pole.
Also note that for certain circuit breakers it is extremely difficult to separate the pre-insertion contacts from the main contacts.

Contrary to the standard test results, the detailed test produces separate timing curves for each main contact and each pre-insertion contact.
Thanks to the separate recordings, the overlap time appears immediately.

How to choose a test method?
The answer to this question depends on the tests that need to be performed.
Standard tests are needed when performing a preventive inspection.
Detailed tests are performed when a circuit breaker is put into service or when there is a repair or a part is modified.

How to connect the command cables?
The close command cable is connected in parallel with the Close pushbutton, shown on the schematic by point number seven.
The open command cable is then connected to the protection point indicated by point number nine.
-Finally, the black cable is connected to point number three which is the 129 volts power supply.
Note that when the close command cable is connected to point number seven, the 52 X intermediate relay lengthens the closing time, typically by about ten milliseconds, and reduced the current drawn by the 52 X relay coil.
-This may be corrected by connecting the close command cable directly across the 52 CC coil.

Question lesson 2
When a circuit breaker is put into service, the test to be performed is:
1. the standard test.
2. the detailed test
The answer is two, the detailed test. See slide 8 for more details

References
Circuit breaker timing
Circuit breaker libraries