DEIF DM-4 Marine&Offshore Ship Power Management System

DEIF DM-4 Marine&Offshore Ship Power Management System

In the fields of ship electric propulsion, offshore platforms, and complex marine equipment, the reliability, flexibility, and maintainability of the power system are directly related to operational safety and efficiency. The Delomatic 4 DM-4 Marine&Offshore system (hereinafter referred to as DM-4) launched by DEIF is a distributed power management platform designed specifically for harsh marine environments. It inherits DEIF's more than 20 years of experience in ship generator control and deeply optimizes for complex working conditions such as DP 2/3 power positioning, multi busbar segmentation, and shaft generator/motor switching. This article is based on the DM-4 data manual and systematically elaborates on its system architecture, core modules, protection functions, communication networking, and engineering application points, providing comprehensive technical references for ship electrical engineers and system integrators.

System positioning and applicable scenarios

DM-4 is a highly flexible power management system suitable for complex ships and offshore power stations that include diesel engines, gas turbines, and shaft generators. Its typical applications include:

Diesel electric propulsion (including DP 2 and DP 3 grades)

Supply vessel (equipped with 2 shaft mounted generators and 2 or more diesel generators)

Shaft driven generator doubles as an electric motor (reversible operation)

Multi bus system (including bus tie circuit breaker control)

Offshore platforms and drilling platforms (including gas turbines)

Shore power connection management

The system supports integrated control of up to 15 generator sets and can also manage bus tie circuit breakers and shore power circuit breakers. Each DGU (DEIF Generator Unit) is equipped with a high-precision three-phase measurement circuit, and all electrical parameters and alarm information are displayed through an LCD display unit. The system comes standard with an AOP-1 additional control panel (for the main DGU) and can be connected to up to 5 AOP-2 remote control panels via CANbus, with a maximum distance of 200m, enabling dual control both locally and in the control room.

Hardware modular design

The most prominent feature of the DM-4 system is that it only requires four hardware modules to build a complete system, greatly simplifying spare parts inventory and maintenance complexity:

1. PCM 4-1/PCM 4-5 (8TE wide)

The system core module integrates power supply, main CPU, and I/O router.

PCM 4-1 (spare/replacement): Provides 3-channel CAN, 1-channel RS485, DM-4 LAN, and USB service ports.

PCM 4-5 (standard): Provides 2 CAN channels, 2 RS485 channels (with one channel up to 115 kbps), 1 Ethernet channel (supporting Modbus TCP/IP and USW connections), DM-4 LAN and USB ports.

Both support 24V DC power supply (-25%/+30%), maximum current of 6A, and have battery voltage measurement function (accuracy ± 0.8V).

2. IOM 4-1 (6TE wide)

Universal I/O module, including:

16 input channels: can be independently configured as current input (0-20mA), voltage input (0-10V), or binary input (dry contact) through jumper wires. Support active zero point (such as 4~20mA, 2~10V), precision 10 bit resolution, impedance: mA input 50 Ω, V input 15k Ω. Binary input ON detection maximum resistance 100 Ω, optional cable monitoring (requires external 270 Ω resistor).

12 relay outputs: programmable as normally open or normally closed (closed/open), with contacts rated at 250V AC/24V DC, 8A. All outputs will automatically disconnect when power is lost.

2 analog outputs: 0~20mA (offset of 4~20mA), maximum load of 500 Ω, accuracy Class 0.5, 10 bit resolution, and isolated from other circuits in the system (500V AC, 1min). When power is lost, the output returns to zero.

3. SCM 4-1 (6TE wide)

Multi functional transmitter module, integrated with:

High precision three-phase electrical measurement (Class 0.5, compliant with IEC 688)

Integrated synchronizer and circuit breaker control

Suitable for generator or busbar applications

4. SCM 4-2 (12TE wide)

Added on the basis of SCM 4-1:

Governor (GOV) and Voltage Regulator (AVR) Control Board (Supports Binary or Analog Output)

Suitable for generator control that requires direct drive speed regulation/excitation

Each DGU can install up to 4 synchronization modules (SCM 4-1/4-2), which can control 1 generator circuit breaker (GB), 2 bus tie circuit breakers (TB), and 1 shore power circuit breaker (SC), achieving a compact configuration. But each DGU only controls 1 GB, which is based on the requirements of the classification society and the design conventions of the switchgear section.

Rack size: Available in four standard racks: 24, 30, 42, and 60TE, selected based on the number of I/O and synchronization modules. For example, a 30TE rack can accommodate 3 I/O slots, 42TE has 5 slots, and 60TE has 8 slots.

Display and operation panel

Display Unit (DU): Independently installed, connected to DGU through display cables, each DGU can connect up to 3 DUs to achieve multi location monitoring. DU size 115 × 220 × 20mm, see manual for panel openings.