Basler Electric DECS-200N Negative Forcing Digital Excitation Control System

The DECS-200N is a very compact Negative Forcing Digital Excitation Control System.

This compact design accommodates 63 Vdc and 125 Vdc applications up to 20 Adc

continuously. The on-board six-thyristor controlled rectifier bridge offers the highest

system performance possible, making the DECS-200N ideal for providing exceptional

system response, which makes it suitable for applications requiring power system

stabilizers.

FEATURES

• Multiple microprocessor-based design

• True RMS sensing, single or three phase

• ±0.25% Voltage Regulation Accuracy

• 63 Vdc and 125 Vdc output capability up to 20 Adc continuous

• Built-in 6 SCR power bridge

• Negative field forcing

• Highly compact design

• High initial response

• Soft start buildup

• Var and Power Factor operating modes with Autotracking

• Autotracking between operating modes and between dual DECS-200Ns

• On and off-line Overexcitation Limiter

• Customizable Underexcitation Limiter

• Stator Current Limiting

• Underfrequency compensation or V/Hz Ratio Limiter

• Field flashing control provisions

• Paralleling provisions

• Generator Protection

• Exciter Diode Monitoring (EDM)

• Oscillography and Sequence of Events Recording

• Voltage Matching

• 5 Programmable output contacts

• Modbus™ protocol via RS-485 communications

The DECS-200N is a multi-microprocessor based Negative

Forcing Digital Excitation Control System designed into one

complete compact package. This space-saving design

consists of all the functionality needed to control, limit and

protect a generator from operating outside the machine's

capability. This is accomplished by the DECS-200N's

impressive control algorithm coupled with a versatile 20Adc

6 SCR power bridge. The input of the power bridge can be

fed by a 50 to 500 Hz, single or three phase voltage source,

depending on the desired excitation levels it is intended to

support.

DESCRIPTION

The DECS-200N also incoporates four control modes of

operation: Automatic Voltage Regulation (AVR), Field

Current Regulation (FCR, Manual), Volt Amp Reactive (Var)

and Power Factor (PF) control. In addition to these control

modes, the DECS-200N provides the ability for all non-active

control modes to follow the set point of the active mode,

permitting bumpless transfer between any other modes. For

applications requiring redundancy, the DECS-200N can

communicate unit-to-unit, allowing the backup DECS-200N

to automatically follow the active unit's set point in the event

it is necessary to switch to the backup DECS-200N. Commu

nications with a PC is possible via a front panel RS-232 port

for local programming and metering. Provisions for remote

control are also available using contact inputs and the RS

485 port via Modbus protocol. The DECS-200N offers all of

the features, functionality, flexibility, and programmability for

use in new installations and in retrofit applications.

APPLICATION

The DECS-200N is a highly responsive negative forcing excitation

control system used to control the output voltage, vars, or power

factor of a synchronous generator by automatically adjusting the

amount of dc excitation being applied to the generator's exciter field.

Due to its negative forcing capabilities, the DECS-200N is ideal for

virtually any size system that demands exceptional system response

and/or requires Power System Stabilizers.