Basler Electric manufactures a complete line of precision voltage regulators, both digital and analog, that will improve and optimize generator system performance for any application. Whether it's prime power or emergency back-up power, Basler Electric has regulators for high performance and reliability. We offer regulators that are CSA certified and come standard with an 18-month warranty,

Digital Excitation Control System Family

DECS-100 — DECS-200 — DECS-200N — DECS-400

Digital Excitation Control System (DECS-100)

This environmentally rugged digital excitation control system is ideally suited for controlling the output of brushless excited synchronous generators up to 5MW. The DECS-100 is extremely affordable and perfect for machines that will be paralleled to other generators and/or to the utility system. It is ideal for distributed generation, co-generation and peak shaving applications.

Features include:

• 0.25% Voltage Regulation Accuracy
• 0.5% accuracy up to 40% THD (harmonics associated with 6 SCR load)
• 63Vdc @ 7Adc PWM output
• 0-3X V/Hz limiting
• Soft Start capability
• 20 standard stability selections and one customizable selection
• VAR/PF control (Optional selection)
• Underexcitation Limiting (UEL)
• Overvoltage Time Delay
• Takeover Style Overexcitation Limiting (OEL) Characteristic
• Voltage Matching Features:
  -Bus Voltage Matching Provisions
  - Voltage Set Point Selections: Maintain Mode and Revert Mode
• Overexcitation limiting
• Manual Mode (Field current regulation)
• Paralleling input from 1 or 5A CT secondaries (Optional selection)
• Nominal sensing inputs of 120, 240, 480 and 600Vac
• Power Input from 50/60Hz shunt connections or PMGs operating at 50 to 400Hz
• Five generator protection functions including Loss of Sensing transfer to manual
• Alarm Contact Output
• Accessory input
• LED Annunciation of operating conditions
• Setup via PC via BESTCOMS software (included)
• cURus Agency Recognition
• DNV Marine Type Approval (Det Norske Veritas). Click to download.
• The ICRM minimizes inrush currents on voltage regulators that incorporate Pulse Width Modulated (PWM) technology.

Download Bulletin SZN for more information or download the product manual.

Digital Excitation Control System (DECS-200)

One DECS-200 Digital Excitation Control System can accommodate 32Vdc, 63Vdc, or 125Vdc applications up to 15Adc. This unique flexibility provides precision control of virtually any size generators. The DECS-200 also incorporates a pulse width modulated power stage, which improves system performances in non-linear load applications.

Features include:

• True RMS sensing, single or three phase
• 32Vdc, 63Vdc, and 125Vdc outputs at 15Adc
• 0.25% Voltage Regulation Accuracy
• Setup from front panel HMI or by PC with Windows® setup software included
• 20 standard stability selections plus a user customizable stability selection
• Paralleling compensation
• Underfrequency compensation or V/Hz Ratio Limiter
• Softstart buildup
• Field Current Regulation Mode (Manual Mode)
• Autotracking between operating modes standard and between DECS-200 units optional
• Remote setpoint control via:
• Contact inputs
• Proportional control via ±10Vdc or 4-20mA
• Communications inputs RS-232 (ASCII) or RS-485 (Modbus™)
• Minimum Excitation Limiter (Internally generated or customizable)
• On and off-line Maximum Excitation Limiters
• VAR and Power Factor Controllers 
• Voltage Matching
• Seven generator protection features
• Programmable output contacts
• Front panel backlit LCD display and front panel mounted RS-232 and side RS-485 communications ports
• Exciter Diode Monitoring (EDM)
• Sequence of Event Recording (SER)
• Oscillography
• Modbus™ protocol for RS-485 input allows communications up to 4,000 feet away
• <1% metering accuracy for 12 generator parameters
• CSA certified, UL recognized, CE compliant
• DNV Marine Type Approval (Det Norske Veritas). Click to download.

Download Bulletin SZM for more information or download the product manual.

An evaluation copy of the BESTWAVEPlus COMTRADE Analysis Software is shipped with each DECS-200. BESTWAVEPlus is a high-resolution graphical analysis interface designed for the display, analysis and management of fault files in the standard IEEE COMTRADE file format. For more details or to download the manual, visit the BESTWAVEPlus page.

Read about the DECS-200 in action in these Application Notes:

• EX-D200P3 describes the DECS-200 pre-packaged retrofit solution for use on small to medium size synchronous machines with brush or brushless type rotating exciters.
• EX-D200SILV - the DECS-200 Kit designed to replaceWestinghouse Silverstat voltage regulators.
• EX-D200SRA - the DECS-200 Kit designed to replace the SR4A and SR8A voltage regulators, for generators ranging from 250 kW to 7 MVA.
• EX-D200VR - the DECS-200 Kit designed to replace Electric Machinery VR voltage regulators.
• EX-MAVR1 -Addresses the benefits of replacing the BRUSH model MAVR voltage regulator with a DECS-200.

The Remote Display Panel (RDP-300) provides remote control, metering, status and alarms for the DECS-200. The ICRM minimizes inrush currents on voltage regulators that incorporate Pulse Width Modulated (PWM) technology. Read more in Application Note RSC-ICRM.

DECS-200N Negative Forcing Digital Excitation Control System

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

This multiple microprocessor-based 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.

For more information on negative field forcing voltage regulators and power system stabilizers, see the technical paper "Suitability of Excitation Systems for PSS Applications" from the Power Engineering Society General Meeting, 2003

Features
   • True RMS sensing, single or three phase
   • ±0.25% Voltage Regulation Accuracy
   • 63 Vdc and 125 Vdc output capability up to 20 Adc continuous
   • Negative field forcing
   • 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
   • Setup via Windows®-based BESTCOMS software

Download Bulletin SZO for more information or download the product manual.

An evaluation copy of the BESTWAVEPlus COMTRADE Analysis Software is shipped with each DECS-200N. BESTWAVEPlus is a high-resolution graphical analysis interface designed for the display, analysis and management of fault files in the standard IEEE COMTRADE file format. For more details or to download the manual, visit the BESTWAVEPlus page.

For a quick comparison of the DECS-200 and DECS-200N, download our Comparison Chart.

The negative field forcing capability of the DECS-200N offers tuning advantages for rotating exciter systems. See Application Note EX-D200N1 for details.

Digital Excitation Control System (DECS-400)

The DECS-400 is a microprocessor-based controller that provides excitation control, flexible logic control, and optional power system stabilization for synchronous machines in an integrated package. The controller provides an analog output to control the firing of external bridge(s) and monitors machine parameters to control, limit, and protect the synchronous machine from operating beyond its capability limitations.

The optional Power System Stabilizer is an IEEE-type PSS2A, dual input, "integral of accelerating power" stabilizer that provides supplementary damping for low-frequency local mode, inter area, and inter unit power system oscillations.

Other features include:

• Five Control Modes, with autotracking between modes
  - Automatic Voltage Regulation (AVR)
  - Field Current Regulation (FCR)
  - Power Factor (PF)
  - Field Voltage Regulation (FVR)
  - Var Control
• 0.20% Voltage Regulation Accuracy
• Two pre-position set points for each mode
• Two Programmable Analog Outputs
• Setup from Front Panel HMI or by PC (local or remote)
• 40 Standard Stability Settings
• Time synchronization using IRIG or NTP (via Ethernet)
• Optional Integral Power System Stabilizer
  - Dual input, integral of accelerating power (IEEE PSS2A/2B)
  - Customer selectable speed-only sensing
  - Two wattmeter power measurement
  - Optional Frequency Based Operation
  - Generator or Motor control modes
• Customizable Stability Setting with two PID setting groups
• Reactive Droop, Line Drop Compensation
• Generator Voltage Soft-Start during Buildup
• Real Time Metering for 19 Generator Parameters
• Voltage Matching
• Autotracking with Optional Backup DECS-400
• Flexible Remote Set point Control
  - Contact inputs
  - Proportional Analog input, 10 Vdc or 4-20 mA
  - Digital Communications
• Local RS-232, ASCII, Modem Capabilities
• RS-485, Modbus™, RJ-45 Ethernet
• Built-in limiting functions
  - Overexcitation Limiters - Summing Point or Takeover Type
  - Underexcitation Limiters - 5 point user programmable or internally generated, summing point or takeover
  - Dual Slope Voltz/Hz Ratio or Underfrequency Limiter
  - Stator Current Limiter (single phase or three phase)
• Built-in Protective Functions
  - Field Overvoltage and Overcurrent
  - Generator Undervoltage and Overvoltage
  - Loss of Sensing Voltage
  - Loss of Field (40Q)
  - Field Overtemperature (for main field)
  - Dual Slope Volts/Hertz (24)
  - Exciter Diode Failure (for brushless exciters)
  - Generator Frequency less than 10 Hz
• Setup and initial operation are facilitated by BESTCOMS, which offers:
  -real time monitoring test analysis
  -flexible oscillography, trending
  -expanded testing capabilities, including means for performing frequency response tests
• Sixteen Contact inputs - 10 user-programmable
• Eight Contact Outputs - 6 user-programmable
• Metering - Two 4-20mA meter drivers, customer programmable
• Four Communication Ports
• Data Logging, Sequence of Events Recording, Trending, real time monitoring test analysis, and built-in frequency response test capabilities
• UL Recognized, CSA certified, CE Compliant, GOST-R certified per the relevant standards of Gosstandart of Russia, Byelorussian certified

Download Bulletin SZF for more information or download the product manual.

For details on the DECS-400 as part of a Static Exciter system, please download our standard exciter specification. DECS-400 Application Notes also are available.