9287500991 Rev K DECS-100 Functional Description i
SECTION 3 • FUNCTIONAL DESCRIPTION
TABLE OF CONTENTS
SECTION 3 • FUNCTIONAL DESCRIPTION ........................................................................................... 3-1
INTRODUCTION.................................................................................................................................... 3-1
DECS-100 FUNCTION BLOCKS ........................................................................................................... 3-1
Analog Input Circuits .......................................................................................................................... 3-1
Bus Voltage..................................................................................................................................... 3-1
Generator Voltage .......................................................................................................................... 3-1
B-Phase Line Current ..................................................................................................................... 3-2
Accessory Input (Auxiliary Adjust) .................................................................................................. 3-2
Field Voltage ................................................................................................................................... 3-2
Field Current ................................................................................................................................... 3-2
Contact Input Circuits ......................................................................................................................... 3-2
Raise ............................................................................................................................................... 3-2
Lower .............................................................................................................................................. 3-2
Var/Power Factor Control (52J/K) Option ....................................................................................... 3-2
Parallel Generator Compensation (52L/M) ..................................................................................... 3-2
Voltage Matching Control Option .................................................................................................... 3-3
RS-232 Communication Port.............................................................................................................. 3-3
Microprocessor ................................................................................................................................... 3-3
Power Input Stage .............................................................................................................................. 3-3
Power Supply ..................................................................................................................................... 3-3
Power Amplifier Stage ........................................................................................................................ 3-3
Front Panel Indicators ........................................................................................................................ 3-3
Relay Output....................................................................................................................................... 3-3
DECS-100 OPERATING FEATURES ................................................................................................... 3-3
Operating Modes ................................................................................................................................ 3-3
Automatic Voltage Regulation Mode .............................................................................................. 3-3
Manual Mode .................................................................................................................................. 3-4
Var Control Mode (Optional) ........................................................................................................... 3-4
Power Factor Control Mode (Optional) ........................................................................................... 3-4
Reactive Droop Compensation .......................................................................................................... 3-4
Underfrequency .................................................................................................................................. 3-4
Protection ........................................................................................................................................... 3-4
Generator Overvoltage ................................................................................................................... 3-5
Loss of Sensing Voltage ................................................................................................................. 3-5
Field Overvoltage (Overexcitation Shutdown) ................................................................................ 3-5
Limiters ............................................................................................................................................... 3-6
Overexcitation Limiting ................................................................................................................... 3-6
Underexcitation Limiting ................................................................................................................. 3-6
Soft Start ............................................................................................................................................. 3-6
Voltage Matching (Optional) ............................................................................................................... 3-6
Figures
Figure 3-1. Simplified DECS-100 Block Diagram ...................................................................................... 3-1