Basler DGC-2020 Generator Set Controller: Integrated Control and Debugging Guide

Basler DGC-2020 Generator Set Controller: Integrated Control and Debugging Guide

Introduction: Integrated solution for generator set control

In modern power generation systems, the generator set controller undertakes multiple tasks such as engine control, generator protection, load management, and system communication. Traditional solutions often require multiple discrete devices to work together - one for engine control, one for generator protection, and independent synchronizers and load distributors, which not only increases system complexity but also raises fault points and maintenance costs.

The DGC-2020 digital generator set controller from Basler Electric is an integrated solution designed to address this challenge. It integrates engine generator control, protection, metering, and communication functions into a single package, achieving precise measurement, setpoint adjustment, and timing functions through microprocessor technology. This article will provide a comprehensive technical reference for engineers in the power generation field from four dimensions: system architecture, core functions, debugging process, and practical applications.

System Overview and Core Functions

1.1 Product positioning

DGC-2020 is a digital controller that integrates engine generator control, protection, and metering, designed specifically for diesel generator applications. It can be widely used for emergency backup power, main power, and marine power generation systems. Its core advantage lies in integrating traditional functions that require multiple independent devices to complete, including:

Engine start/stop control

Generator protection (overvoltage, undervoltage, reverse power, demagnetization, overclocking, underflocking)

Automatic synchronization and parallel operation

Automatic transfer switch (ATS) control

Load allocation and unit sorting

CANbus communication (SAE J1939/MTU protocol)

Best Logic+

1.2 Style Number and Expansion Capability

DGC-2020 defines functional configurations through style numbers. For example, style number 51BNBMEAH represents:

5Aac current sensing

50/60Hz rated frequency

12 programmable output contacts

Real time clock with battery backup

Built in dial-up modem

Enhanced generator protection (including overcurrent and phase imbalance)

Automatic synchronizer

LCD heater (suitable for low temperature environment)

In addition, DGC-2020 can further expand its functionality through three expansion modules:

LSM-2020: Load distribution module, realizing kW/kVar distribution when multiple machines are connected in parallel

CEM-2020: Contact expansion module, adding 10 inputs and 24 outputs

AEM-2020: Analog expansion module, adding 8 analog inputs, 8 RTD inputs, 2 thermocouple inputs, and 4 analog outputs

Key points for hardware installation and electrical connection

2.1 Installation specifications

DGC-2020 is installed using four permanently fixed 10-24 bolts and requires the use of the provided self-locking nuts. The tightening torque should not exceed 25 inch pounds. The front protection level is IP54, with the ability to resist moisture, salt spray, dust, and chemical pollution.

Critical safety warning:

The equipment must be reliably grounded using copper wire of no less than 12 AWG

The polarity of the working power supply must be correct (reverse connection does not damage but cannot work)

Idle current sensing input should be short circuited to reduce noise coupling

2.2 Core Wiring Instructions

Working power supply (terminal 3 positive, 2 negative):

Nominal voltage: 12 or 24 Vdc

Scope of work: 6-32 Vdc

Can withstand starting voltage drop as low as 6Vdc for 500ms

Voltage sensing:

Generator: Terminal 41 (Phase A), 39 (Phase B), 37 (Phase C), 35 (Neutral)

Busbar: Terminal 45 (Phase A), 43 (Phase B)

Range: 12-576 Vac (line voltage)

Current sensing:

1A or 5A CT input (determined by style number)

Terminals 68/69 (phase A), 71/72 (phase B), 74/75 (phase C)

CT primary range: 1-5000A

CANbus interface (communication with ECU and expansion module):

Terminal 49 (CAN H), 48 (CAN L), 50 (shielded)

Speed: 250kb/s

Key precautions:

Both ends of the bus must be connected with 120 Ω terminal resistors

The length of the controller's stub must not exceed 914mm

The total length of the bus (excluding branches) shall not exceed 40m

The shielding layer is only grounded at one end

Engine sensor input:

Oil pressure: Terminal 8, compatible with Datcon 02505-00, Isspro R8919, etc

Coolant temperature: Terminal 10, compatible with Datcon 02019-00, Faria TS4042, etc

Fuel level: Terminal 9, compatible with Isspro R8925, etc

Sensor common terminal: Terminal 11

Operation mode and running logic

3.1 Three operating modes

OFF mode: The controller will not start the generator under any conditions. The programmable logic function is running normally.

RUN mode (manual): The generator continues to run and cannot automatically shut down. The opening and closing of the circuit breaker can be controlled through contact input or logic. The programmable logic is running normally.

AUTO mode: The generator can automatically start according to the following conditions:

ATS (Automatic Transfer Switch) input

Generator timed self-test (Exercise Timer)

Mains Fail Transfer

Run with Load logic input

Demand Start/Stop

3.2 Self activation logic

The self starting modes of DGC-2020 are independent of each other but have priority logic. If any starting condition is true, the unit will operate; The unit will only shut down when all start-up conditions are false. This design ensures reliable operation under various working conditions.

Circuit breaker management and automatic synchronization

4.1 Circuit Breaker Control

DGC-2020 can control both generator circuit breakers and mains circuit breakers simultaneously. Supports two contact output modes:

Pulse mode: emit pulses of the set width (0.01-0.80 seconds)

Continuous mode: Continuous output holding (applicable to circuit breakers with holding coils)

Before closing the circuit breaker, the controller will verify:

Stable voltage on the generator side

The voltage on the busbar side is stable or determined to be a dead busbar

Synchronization condition met (when closed to live busbar)

4.2 Synchronizer Operation

The automatic synchronizer of DGC-2020 supports two modes:

Phase Lock Loop mode:

The controller adjusts the generator voltage and frequency through the rise and fall signals of the speed regulator and AVR

When the voltage difference, frequency difference, and phase angle difference all meet the set values, issue a closing command

Predictive mode:

Added circuit breaker closing time compensation on the basis of PLL

The controller calculates the advance phase angle based on the measured slip frequency to ensure that the phase angle approaches zero at the moment of circuit breaker contact closure

Troubleshooting steps for synchronizer not working:

Confirm that the style number includes a synchronizer option

Check if the GEN STANBLE and BUS STANBLE status indicator lights are on

Confirm that the controller is initiating a closing request

If the synchronization stops after a brief activation, check if a Sync Fail pre alarm has been triggered

Load distribution and parallel connection of multiple machines (LSM-2020)

5.1 Load distribution principle

DGC-2020 is used in conjunction with LSM-2020 load distribution module to achieve parallel operation of multiple machines. The core mechanism is to simulate load distribution lines:

Each generator's LSM-2020 outputs a 0-10V signal, which is proportional to the actual output kW of the unit

The load distribution lines of all units are connected together, and the intersection voltage reflects the average value per unit of the total system load

Each unit adjusts its own output by using the intersection voltage as the set value for the kW controller

5.2 Parameter tuning of PID controller

Load distribution involves three PID controllers:

Speed controller: Adjust engine speed before parallel synchronization

Voltage controller: Adjust the generator voltage during synchronization before parallel connection

KW load controller: regulating active power distribution during parallel operation

Basic process of parameter tuning:

Set all gains to zero

Adjust the proportional gain (Kp) until the system approaches instability, and then reduce it to half of that value

Using one tenth of Kp as the initial value of the integral gain (Ki), gradually increase it until it becomes unstable and then halve it

If overshoot needs to be reduced, introduce differential gain (Kd) and use it in conjunction with filtering constant (Td)

5.3 Unit sorting and load management

DGC-2020 supports automatic unit start stop sorting based on the following principles:

Rotation of running time: prioritize starting based on the minimum number of running hours

Balanced running time: prioritize starting based on the maximum number of running hours

Capacity priority: Start the unit with the highest or lowest capacity first

ID sorting: Start in sequence according to the set sorting ID

The Demand Start/Stop function automatically starts and stops the unit based on the total system load, achieving economic operation.

CANbus communication and ECU integration

6.1 Supported ECU protocols

The CANbus interface of DGC-2020 supports:

SAE J1939 standard protocol: obtains oil pressure, coolant temperature, engine speed, and can read diagnostic trouble codes (DTCs)

MTU protocol: supports MTU MDEC, MTU ADEC, and MTU ECU7, and can obtain MTU specific alarm and pre alarm information

Volvo Penta Protocol: Supports EDC3 and EMS2 controllers

6.2 ECU Power Management

For ECUs that require power-off to shut down (such as some Detroit Diesel J1939 ECUs), DGC-2020 provides four timer settings:

Engine shutdown time: The time (1-60 seconds) for the ECU to remain powered off after shutdown, ensuring that the engine comes to a complete stop

Pulse cycle: The interval (1-60 minutes) between ECU re powering to obtain data

Stabilization time: The time it takes for data to stabilize after power on (5.5-30 seconds)

Response timeout: Maximum waiting time for attempting communication (1-60 seconds)

6.3 Diagnostic Trouble Code (DTC)

DGC-2020 can receive and store DTCs from ECU. Each DTC contains:

SPN (Suspicious Parameter Number): Identify the diagnostic object

FMI (Failure Mode Identifier): Define the type of fault

Number of occurrences: Record the number of fault activations

Both the current active DTC and the previously cleared active DTC can be viewed through HMI or BESTCOMSPlus.

Alarm and protection functions

7.1 Alarm Grading

DGC-2020 distinguishes three alarm levels:

Pre Alarm: Indicates situations that require attention but are not yet urgent, flashing alarm LED, programmable output to horn

Alarm: Indicates a serious malfunction and immediately shuts down the machine

Status Only: Used for monitoring only, does not trigger alarms

7.2 Key Protection Parameters

Description of Protection Function Setting Range

Undervoltage (27) 70-576 Vac, two independent set values, supporting single/three-phase mode

Overvoltage (59) 70-576 Vac, two independent set values, supporting single/three-phase mode

Underfrequency (81U) 45-65 Hz with voltage suppression function

Overfrequency (81O) 45-65 Hz-

Reverse power (32) -50% to+5% set as a percentage of rated power

Demagnetization (40Q) -150% to 0% set according to the rated reactive power percentage

16 types of inverse time curves for overcurrent (51) optional components

7.3 Low Line Scale Factor

This is a feature of DGC-2020: when a contact input (programmed as Low Line Override) is detected to be closed, the protection setting value is automatically multiplied by a scaling factor. This function is applicable to reconfigurable generator sets that can operate at different voltage levels.

BEST logic+programmable logic

BEST logic+is the "electronic wiring" system of DGC-2020, which connects input, output, protection components, and logic gates through graphical drag and drop to achieve customized control strategies.

Programming constraints:

Each multi input entry requires a minimum of 2 inputs and a maximum of 4 inputs

Up to 5 levels of logical depth for any path

Up to 10 gates per level of logic

Up to 64 connection points for all paths

Common logical objects:

Input objects: physical inputs IN1-IN16, virtual inputs VIN1-VIN4

Output objects: physical outputs OUT1-OUTx, remote outputs OUT13-OUT36

Protective components: 27TRIP, 59TRIP, 51TRIP, 32TRIP, 40TRIP

Control components: AVR (voltage regulator), GOVERNOR (speed regulator) GENBRK/MAINSBRK

Logic gates: AND, OR, NAND, NOR, XOR, NOT

Typical applications:

Map ATS input to automatic generator start

Route the protection trip signal to the designated output contact

Implement timing control for delayed startup, cooling shutdown, etc

Troubleshooting Guide

9.1 The generator circuit breaker cannot close to the dead busbar

Confirm that the closing request has been initiated

Set DEAD BUS CL ENBL to ENABLE in BREAKER HARDWARE

Confirm that the generator status is stable (GEN STANLE indicator light is on)

Confirm that the bus status is DEAD (BUS DEAD indicator light is on)

Adjust the dead bus threshold and delay in BUS Deliberation Protection

9.2 The generator circuit breaker cannot be closed to the live busbar

Confirm that the synchronizer option exists

Confirm that both the generator and busbar are in a stable state

Check if the synchronizer is actively working (observe the speed regulator/AVR rise and fall pulses or simulate bias voltage changes)

Confirm that the Sync Fail activation delay is long enough

9.3 CANbus communication failure

Confirm that there is a 120 Ω terminal resistor at each end of the bus

Check that the CAN H and CAN L connections are not reversed

Confirm that the bus length is ≤ 40m and the branch line is ≤ 3m

Confirm that the ECU configuration settings match the actual ECU type (Volvo/MTU/standard J1939)

9.4 Abnormal sensor readings

Confirm that the sensor common terminal (terminal 11) is connected to the negative terminal of the battery and the sensor on the engine side

Measure with a multimeter that there is no voltage difference between terminal 2 (BATT -) and terminal 11

The sensor circuit should be routed separately from the AC power line and ignition line, using independent conduit