Vanguard CT-7500 User Manual

Page 57

MODEL CT-7500

OPERATING INSTRUCTIONS

Rev 2 Jan 2001

9.14.7 Analysis Point No.1.

Three selections are available to the user for setting analysis point No. 1:

1. PERCENTAGE OF STRK
2. DISTANCE FROM CLOSE
3. CONTACT #1

a. Percentage of Stroke:

Percentage of stroke is distance based upon percentage of total breaker stroke distance.

This distance is always measured from the starting point at the fully closed position of the
breaker contacts.

b. Distance From Close:
Distance from Close range is selectable from 00.0 inch to 99.99 inches or from 0.0
centimeter to 99.90 centimeters. Again, this distance is referenced from the contact's
closed position.

c. Contact Point #1:
Contact point is the distance from the contact's closed position to the point where it is in
transition from close-to-open (or open-to-close position). Contact channel #1 will be used for
this selection.

9.14.8 Analysis Point No. 2.

Only two selections for analysis point 2 are available to the user:

1. PERCENTAGE OF STRK
2. DISTANCE FROM CLOSE

The selection of analysis point No. 2 is the same as for analysis point No. 1.

NOTE

1. Average velocity through the arc zone is calculated by using the following formula:

ave

= Distance

Time

2. The current breaker contact velocity will be recalculated based on data stored in memory
(RAM) after any new analysis point(s) is selected. The user does NOT need to operate the
breaker again to acquire new contact velocity data after changing the analysis points (a new
velocity is calculated from travel data stored in memory from the last operation).

3. For complex velocity calculations, the user can download a test plan to the CT-7500 from an
IBM PC. This test plan can be recalled and used to calculate a breaker's contact velocity.