WhatsApp: +86 16626708626
Email: 
Phone: +86 16626708626Description
Key Technical Specifications
- Manufacturer: DEIF A/S
- Model: GPU/2/GS
- Product Family: Multi-line 2 version 2
- Product Type: Microprocessor-based generator protection unit
- Primary Application: Generator electrical protection
- Supply Voltage: 12/24 V DC
- Supply Tolerance: −25%/+30%
- AC Measurement: Three-phase true RMS
- Generator Voltage Input: Maximum 690 V AC phase-to-phase
- Generator Current Inputs: 1 A or 5 A CT secondary
- Protection Functions: Reverse power ANSI 32; one- and two-stage overcurrent ANSI 51
- Protection Options: Depending on hardware/software options, including additional voltage, frequency, earth-fault, and ROCOF functions
- Relay Outputs: Configurable relays rated up to 250 V AC / 8 A
- Status Relay: Normally closed processor/power-supply supervision contact, 24 V / 1 A
- Pulse Outputs: Two open-collector outputs for kWh and kVArh counters
- Binary Inputs: Optocoupler inputs, configurable by option and terminal assignment
- Analog Outputs: Optional 0/4–20 mA outputs
- Engine Interface: Optional 4–20 mA, Pt100, VDO, tachometer, or magnetic-pickup inputs
- Communications: Optional CANopen, Modbus RTU RS-485, Profibus, GSM, or engine-specific interfaces
- Display: Backlit LCD, 4 lines × 20 characters
- Event Log: Up to 150 events
- Mounting: DIN rail or screw-mounted base; marine installations require base mounting
- Operating Temperature: Verify exact hardware revision and option configuration
- Approvals: Major marine societies, Netmanagement, TÜV Nord, GOST-R, and UL
DEIF identifies the GPU as part of the Multi-line 2 family and describes it as a generator protection unit with three-phase true-RMS measurement, 1 A/5 A current inputs, configurable protection, and an event log.
The installation manual lists the GPU/2/GS terminal functions, including 12/24 V DC supply, 690 V AC maximum voltage measurement, 1 A/5 A CT inputs, configurable relay outputs, open-collector energy-pulse outputs, and optional communications.
DEIF has phased out the GPU-2 product and states that it does not currently list a direct replacement. Treat the GPU/2/GS as legacy hardware and verify the exact option code before sourcing a substitute.
Product Introduction
The DEIF GPU/2/GS is a Multi-line 2 generator protection unit for monitoring generator voltage, current, frequency, power, and protection conditions. It provides reverse-power and overcurrent protection, configurable alarms, relay outputs, energy pulse outputs, and an LCD interface for measured values and event records.
The unit is option-dependent rather than a fixed universal I/O controller. CT ratio, voltage range, relay configuration, communications, engine interface, and protection functions must match the installed type code and project settings. DEIF has phased out the GPU-2, so retaining the original configuration records is important.
GPU/2/GS
GPU/2/GS
Troubleshooting Quick Reference
| Symptom | Possible Cause | Relevance to This Part | Quick Check Method | Recommendation |
|---|---|---|---|---|
| Display is blank and no status indication appears | Missing DC supply, incorrect polarity, blown fuse, or internal power fault | ✅ High | Measure 12/24 V DC at terminals 1 and 2 and confirm the supply remains within the permitted tolerance | Check the supply and fuse before replacing the GPU/2/GS |
| Generator voltage reads zero or incorrectly | Blown measurement fuse, wrong voltage wiring, missing neutral, or incorrect configuration | ✅ High | Measure the generator voltage at terminals 79–84 and compare the display value with a calibrated meter | Correct the voltage circuit and configuration before replacing the controller |
| Current readings are wrong | Incorrect CT ratio, reversed CT polarity, open CT circuit, or 1 A/5 A mismatch | ✅ High | Verify CT secondary rating, polarity, ratio settings, and current at terminals 73–78 | Never open an energized CT secondary; correct the CT circuit safely |
| Reverse-power alarm occurs at normal load | CT polarity reversed, phase sequence error, incorrect phase mapping, or wrong setpoint | ✅ High | Compare phase sequence and kW sign with a calibrated power analyzer | Correct phase/CT wiring and verify the reverse-power setting |
| Overcurrent alarm appears without excessive current | Wrong CT ratio, incorrect nominal current, transient pickup, or configuration error | ✅ High | Compare measured current with the CT secondary and programmed nominal values | Verify protection settings and CT wiring before replacing the unit |
| Relay output does not operate | Incorrect configuration, failed relay, missing common, or output option mismatch | ✅ High | Command the relay through the approved test mode and measure continuity between NO and COM | Check the option board and wiring; replace only after relay testing confirms failure |
| Generator breaker status is wrong | Open/closed feedback wired incorrectly or binary-input configuration mismatch | ✅ Medium | Check the breaker auxiliary contact and the assigned binary input state | Correct the field feedback and configuration before changing the GPU |
| Modbus or Profibus communication fails | Missing option board, incorrect address, termination issue, baud-rate mismatch, or wrong protocol | ✅ High | Confirm the installed option, measure RS-485 polarity, check termination, and inspect diagnostic counters | Match the communication option and settings to the original unit |
| Event log or alarm list is unavailable | Display/navigation fault, memory issue, or configuration problem | ✅ Medium | Access the alarm and event menus and compare with the PC utility data | Back up settings and investigate the display or memory subsystem |
| Frequency reading is unstable | Poor voltage signal, generator instability, incorrect wiring, or measurement noise | ✅ Medium | Compare frequency on the GPU with an independent frequency meter | Check generator voltage sensing and phase wiring before replacing the controller |
| Unit resets during generator operation | DC supply dips, electrical noise, grounding issue, or internal fault | ✅ Medium | Trend DC supply voltage during breaker closing and load changes | Improve supply and grounding; replace only after documenting the reset condition |
| Protection does not trip as expected | Alarm inhibit active, wrong setpoint group, option absent, or relay wiring fault | ✅ High | Review active setpoints, inhibit status, event log, and relay continuity | Validate the protection chain with a controlled test before returning the generator to service |
Critical warning: Generator voltage and CT terminals can carry hazardous energy. DEIF warns that installation involves dangerous currents and voltages and should be performed only by authorized personnel. Never open an energized CT secondary, and isolate the generator before changing measurement wiring.
Frequently Asked Questions
What is the DEIF GPU/2/GS?
It is a DEIF Multi-line 2 generator protection unit. It monitors three-phase generator measurements and provides protection, alarms, relay outputs, display functions, and optional communications for generator systems.
What protection functions are standard?
The documented GPU functions include reverse power, ANSI 32, and one- or two-stage overcurrent, ANSI 51. Other functions depend on the selected hardware and software options, so confirm the complete type code before assuming a particular protection feature is installed.
What supply voltage does it use?
The standard GPU/2/GS uses 12/24 V DC with a −25%/+30% tolerance. Measure the voltage at the unit terminals, not only at the panel power supply, because wiring drops and transient dips can cause resets.
Can it measure generator voltage directly?
The Multi-line 2 GPU installation data lists generator voltage inputs up to 690 V AC phase-to-phase. Confirm the actual system voltage, fuse arrangement, neutral wiring, and type-specific configuration before connecting the measurement inputs.
Does it support Modbus?
Modbus RTU over RS-485 is available through the appropriate communication option. CANopen and Profibus are separate options, so inspect the hardware option label and terminal assignment before configuring the network.
Is the GPU/2/GS still manufactured?
DEIF states that the GPU-2 has been phased out and does not currently list a direct replacement. Available units should be treated as legacy stock, and the buyer should request the full option code, serial number, firmware information, and configuration backup.
Can I replace it with a newer DEIF controller?
Possibly, but not as a simple plug-in swap. A replacement must match generator measurements, CT ratios, protection logic, breaker feedback, relay outputs, communications, engine interfaces, display behavior, and configuration software. Plan a controlled engineering change rather than exchanging the front panel alone.
What condition should the listing state?
The listing should identify New Original, New Surplus, or Refurbished and tested. For refurbished stock, request a powered test report covering DC supply, voltage and current measurement, display, relay outputs, binary inputs, communication option, and event-log operation.
