1. Introducere
The Datakom DPR-02 is a three-phase (line to neutral) voltage protection relay engineered to safeguard electrical systems from various voltage anomalies. It provides robust protection against over voltage, sub voltage, and incorrect phase rotation, making it suitable for critical applications in distribution substations, generators, motors, transformers, and compensation systems.
This device offers adjustable over and under voltage limits, along with configurable trip and reset delays, allowing for precise customization to specific system requirements. Both maximum and minimum voltage limits can be set or disabled using trimmers located on the front panel. Corresponding delay times are also adjusted via dedicated trimmers.

Figura 1: Față view of the DPR-02 Voltage Protection Controller, showing adjustment knobs and terminals.
2. Caracteristici
- DIN Rail mounted for easy installation.
- Adjustable over voltage limit (L-N).
- Adjustable under voltage limit (L-N).
- Adjustable TRIP and RESET Delays for precise control.
- Integrated phase sequence protection.
- Detection and protection against phase failure.
- Overvoltagprotecție.
- Protection against insufficient supply.
- 6A/277VAC relay output.
- Suitable for 1-3 phase gasoline and diesel gensets.
- Designed for front panel mounting.
- Survives cranking dropouts.
- Generator protection with built-in alarms and warnings.

Figura 2: Pesteview of DPR-02 features and operational principles.
3. Configurare și instalare
The DPR-02 is designed for DIN rail mounting. Proper installation is crucial for reliable operation. Ensure all power is disconnected before proceeding with wiring.
3.1 Conexiuni terminale
The device features clearly labeled terminals for input and output connections:
- Terminale de intrare: N (Neutral), L1, L2, L3 (Phase voltage intrări).
- Output Relay Terminals: 1 (NC - Normally Closed), 2 (COM - Common), 3 (NO - Normally Open).
3.2 Schema electrică
Refer to the connection diagram below for typical wiring in a motor protection application. Ensure all connections are secure and comply with local electrical codes.

Figure 3: Typical installation diagram for the DPR-02, showing connections for a 3-phase motor.

Figure 4: Detailed connection diagram, LED indicators, and technical specifications.
4. Principii de funcționare
The DPR-02 continuously monitors the line-to-neutral voltages (L-N) and phase sequence to provide comprehensive protection.
4.1 voitage Protection (Under/Over Voltage)
If any phase voltage exceeds the set MAX limit, the "U>" LED illuminates, and the adjusted Delay timer begins to count. If the fault persists beyond the delay, the relay deactivates, the "OUT" LED turns off, and the "U>" LED turns off. Similarly, if any measured voltage drops below the set MIN limit, the "U<" LED illuminates, and the Delay timer starts. If the condition persists, the relay deactivates, and the "OUT" LED turns off, and the "U<" LED turns off.
When the MAX or MIN Voltage trimmer is adjusted to the "OFF" position, the related voltage protection will be disabled.
Toate voltages within adjusted MIN-MAX limits will cause the "U<" and "U>" LEDs to turn off. If the adjusted Reset Delay timer counts to its expiration, the relay output is activated, and the "OUT" LED illuminates.
4.2 Phase Failure Protection
Dacă voltage of any phase falls below 50% of the nominal value, the "U<" LED illuminates, and the relay output immediately deactivates, turning off the "OUT" LED.
4.3 Suprasolicitaretage Protecție
Dacă voltage of any phase goes 50% above the nominal value, the "U>" LED illuminates, and the relay output immediately deactivates, turning off the "OUT" LED.
4.4 Phase Sequence Protection
If the phase sequence is reversed, both "U<" and "U>" LEDs flash, the relay output deactivates, and the "OUT" LED turns off.
4.5 Indicatori LED
The DPR-02 features several LED indicators to provide status feedback:
| U< | U> | ON | OUT | Descriere |
|---|---|---|---|---|
| ON | ON | ON | Voltages OK | |
| ON | ON | Sub voltage avertisment | ||
| ON | Sub voltage excursie | |||
| ON | ON | Peste voltage avertisment | ||
| ON | Peste voltage excursie | |||
| FLASH | ON | Declanșare secvență de fază |
- PE: LED de alimentare (verde)
- OUT: Relay output LED (yellow)
- U<: Sub voltage Warning LED (red)
- U>: Peste Voltage Warning LED (red)
5. Întreținere
The DPR-02 is designed for long-term, reliable operation with minimal maintenance. However, periodic checks can help ensure optimal performance:
- Inspecție vizuală: Periodically inspect the unit for any signs of physical damage, loose connections, or excessive dust accumulation.
- curatenie: If necessary, gently clean the exterior of the unit with a dry, soft cloth. Do not use liquid cleaners or solvents.
- Integritatea conexiunii: Ensure all terminal connections remain tight and secure. Loose connections can lead to intermittent operation or damage.
All maintenance should be performed by qualified personnel with power disconnected.
6. Depanare
If the DPR-02 is not functioning as expected, consider the following common issues:
- Fără alimentare/LED-uri stinse: Verificați volumul de alimentaretage to the N, L1, L2, L3 terminals. Ensure the power source is active and within the specified voltage gama.
- Unexpected Relay Trip: Verificați dacă volumul măsurattages are within the set MIN/MAX limits. Check for correct phase sequence. Review the delay settings (Trip Delay, Reset Delay) to ensure they are appropriate for the application.
- Releul nu se activează: Confirmați că volumul de intraretages are stable and within the acceptable operating range. Check the status of the U< and U> LEDs to identify any active voltage defecte.
- Incorrect Phase Sequence Indication: Double-check the L1, L2, L3 phase connections for correct order.
If issues persist after checking these points, consult a qualified electrician or contact Datakom technical support.
7. Specificații
Detailed technical specifications for the Datakom DPR-02:
| Parametru | Valoare |
|---|---|
| Oferta nominală Voltage | 230V-AC (L-N) |
| Volumul aprovizionăriitage Gama | 150-300 V-AC (L-N) |
| Tip de aprovizionare | Capacitive, 1-phase |
| Gama de frecvente | 47-63Hz |
| Consumul de energie | 30VA / 2W (max) |
| Metoda de măsurare | True RMS, line to neutral |
| Voltage Adjustment Accuracy | 3 % |
| Precizia repetiției | 0.5 % |
| Peste-Voltage Călătoria | 240-300V-AC (L-N) adjustable |
| Sub-Voltage Călătoria | 150-210V-AC (L-N) adjustable |
| Trip Delay Setup | 0.5 - 20 sec. adjustable |
| Reset Delay Setup | 0.5 - 20 sec. adjustable |
| Ieșire releu | 6A @ 277V-AC, 1800VA, 300W |
| Gama cablurilor terminale | 2.5 mm² (12AWG) |
| Screwing Force | 2.4 Nm (3.6 Lb) |
| Temperatura de operare | -30°C (-22°F) până la 70°C (158°F) |
| Temperatura de depozitare | -40°C (-40°F) până la 80°C (176°F) |
| Umiditate maximă | 95% fără condensare |
| Dimensiuni (LxAxD) | 36.0 x 90.6 x 58.4 mm (1.42 x 3.57 x 2.30 inchi) |
| Greutate | ~90 g (3.17 oz) |
| Instalare | DIN Rail mounted |
| Materialul carcasei | High temp. ABS/PC (UL94-V0) |
| Protecție IP | IP30 |
| Conformity (EU Directives) | 2006/95/CE (vol. scăzuttage), 2004/108/CE (EMC) |
| Norms of Reference | EN 61010 (safety requirements), EN 60255-6, EN 61326 (EMC requirements) |
| Țara de origine | Curcan |
8. Garanție și asistență
For information regarding product warranty, technical support, or service, please contact your authorized Datakom distributor or visit the official Datakom website. Ensure you have your product model number (DPR-02) and purchase details available when seeking support.