Littelfuse Startco SE-325 User Manual

Startco Engineering Ltd. Page i
SE-325 Neutral-Grounding-Resistor Monitor Rev. 6
Pub. SE-325-M, May 6, 2008.
TABLE OF CONTENTS
PAGE
Table of Contents ....................................................................i
List of Figures.......................................................................... i
List of Tables ........................................................................... i
1. General ......................................................................... 1
1.1 Modern Resistance-Grounded Systems ....................... 1
1.2 SE-325 NGR Monitoring.............................................. 1
2. Operation...................................................................... 1
2.1 Settings .......................................................................... 1
2.1.1 GF Trip Time................................................... 1
2.1.2 GF .................................................................... 1
2.1.3 Mode ................................................................ 2
2.1.4 RES .................................................................. 2
2.1.5 RES Trip Level................................................ 2
2.2 Indication and Reset......................................................2
2.3 Fusing ............................................................................2
3. Installation.................................................................... 3
3.1 SE-325 .......................................................................... 3
3.2 Ground-Fault CT........................................................... 5
3.3 Sensing Resistor ............................................................ 6
3.4 Isolated-Ground Connection....................................... 12
3.5 Overhead Lines ...........................................................12
3.6 Remote Operation ....................................................... 12
3.7 Ground-Fault Testing..................................................12
4. Technical Specifications ........................................... 12
4.1 SE-325 ........................................................................12
4.2 Sensing Resistors......................................................... 13
4.3 Current Transformer....................................................13
5. Ordering Information............................................... 14
6. Warranty.................................................................... 14
7. Test Procedures ......................................................... 15
7.1 Ground-Fault Performance Test .................................15
7.2 Resistor-Fault Tests..................................................... 16
7.2.1 Open Test ..........................................................16
7.2.2 Voltage Test ......................................................16
7.3 Sensing-Resistor Test..................................................16
LIST OF FIGURES
FIGURE PAGE
1 Typical Application ...................................................... 3
2 SE-325 Outline and Mounting Details......................... 4
3 Current Transformers.................................................... 5
4 ER-600VC Sensing Resistor ........................................ 6
5 ER-5KV Sensing Resistor ............................................ 7
6 ER-15KV Sensing Resistor .......................................... 8
7 ER-25KV Sensing Resistor .......................................... 9
8 RK-302 Remote Indication and Reset ....................... 10
9 RK-325 Remote Indication-and-Reset Assembly ..... 10
10 RK-325I Remote Indication Assembly...................... 11
11 RK-13 Relay Interface Module .................................. 11
12 Ground-Fault-Test Circuits......................................... 15
LIST OF TABLES
TABLE PAGE
1 Settings For Typical Systems ....................................... 2
2 Ground-Fault-Test Record.......................................... 15
DISCLAIMER
Specifications are subject to change without notice. Startco
Engineering Ltd. is not liable for contingent or consequential
damages, or for expenses sustained as a result of incorrect
application, incorrect adjustment, or a malfunction.

Littelfuse Startco SE-325 Specifications

General

Brand	Littelfuse Startco
Model	SE-325
Category	Monitor
Language	English