Vanguard Instruments MCCB-250, User Manual

REV 2

MCCB-250 USER’S MANUAL

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TABLE OF CONTENTS 

CONVENTIONS USED IN THIS DOCUMENT

 ....................................................................... 1

1.0

INTRODUCTION .................................................................................................................... 2

1.1

General Description and Features ................................................................................... 2

1.2

Furnished Accessories ......................................................................................................  2

1.3

MCCB-250 Technical Specifications .................................................................................  3

1.4

Controls and Indicators ....................................................................................................  4

2.0

FUNCTIONAL DESCRIPTION ................................................................................................. 6

2.1

MCCB-250 AC Current Source .......................................................................................... 6

2.2

MCCB-250 Current Output Control ................................................................................. 7

2.3

Timer Stop Input and Control .......................................................................................... 8

2.4

MCCB-250 Timer .............................................................................................................. 9

2.5

External Current Input ..................................................................................................... 9

2.6

LCD Contrast Control ....................................................................................................... 9

3.0

OPERATING PROCEDURES ................................................................................................. 11

3.1

Testing the Time Delay of a Protection Relay ................................................................ 11

3.2

Measuring Current Transformer Primary and Secondary Currents .............................. 13

LIST OF TABLES 

Table 1. MCCB-250 Technical Specifications .................................................................................. 3

Table 2. Functional Descriptions of MCCB-250 Controls and Indicators ........................................  5

Table 3. MCCB-250 Current Output ................................................................................................ 6

Table 4. MCCB-250 Overload Current Output ................................................................................  6

LIST OF FIGURES 

Figure 1. MCCB-250 Controls and Indicators ..................................................................................  4

Figure 2. Typical MCCB-250 Test Results Screen ............................................................................  9

Figure 3. Typical MCCB-250 Application .......................................................................................  11

Figure 4. Typical Current Transformer Current Ratio Test Connections ...................................... 13