Function and Usage
The NJYB3 voltage protection relay is applicable to AC 50Hz, three-phase three-wire 380V, three-phase four-wire 220V circuits, as overvoltage protection, undervoltage protection, phase loss protection, phase sequence protection, three-phase unbalance protection, PTC temperature protection, and load end protection control. For example, it is used in power control systems, air conditioning systems, motors, etc.
Detailed Parameters
| Parameter Category | Parameter Item | Parameter Value |
|---|
| System Parameters | Model | NJYB3 |
| Rated Control Circuit Power Supply Voltage Us | AC220V (three-phase four-wire), AC380V (three-phase three-wire), 50Hz |
| Unbalanced Voltage Setting Value | Rated Control Circuit Power Supply Voltage × Unbalance Rate Setting Value |
| Overvoltage Protection Recovery Voltage | For three-phase three-wire, 6V less than overvoltage action; for three-phase four-wire, 3.5V less than overvoltage action |
| Undervoltage Protection Recovery Voltage | For three-phase three-wire, 6V more than undervoltage action; for three-phase four-wire, 3.5V more than undervoltage action |
| Unbalance Protection Recovery Unbalance Voltage | Unbalance Action Value >75% |
| Phase Loss, Wrong Phase, PTC Temperature Protection Action Time | ≤1s |
| PTC Temperature Protection Characteristics | When R1, R2 resistance ≥1.5KΩ, the relay operates; when R1, R2 resistance ≤500Ω, the relay recovers |
| Delay Error | ±10%, minimum error 0.1s |
| Action Accuracy | Rated Operating Voltage ±3% |
| Mechanical Life | 1×10⁵ times |
| Electrical Life | 1×10⁵ times |
| Display Method | LED light |
| Power Consumption | ≤3VA |
| Ambient Air Temperature | -5℃～+40℃ |
| Pollution Degree | III |
| Installation Method | Track type, device type |
| Basic Parameters of Auxiliary Circuit | Contact Type | 1 set transfer |
| Agreed Heating Current Ith(A) | 3 |
| Usage Category | AC-15 |
| Rated Operating Voltage Ue (V) | 240 |
| Rated Operating Current Ue (A) | 0.75 |
| | 415 |
| | 0.47 |
| Protection Function | Model | NJYB3-1 to NJYB3-18 |
| Wiring Method | Three-phase Three-wire, Three-phase Four-wire, Two-phase Single-phase |
| Overvoltage Protection Adjustment Range (V) | (1.05-1.3)×Us |
| Overvoltage Delay Adjustment Range (s) | 0.1-10 |
| Undervoltage Protection Adjustment Range (V) | (0.7-0.95)×Us |
| Undervoltage Delay Adjustment Range (s) | 0.1-10 |
| Unbalance Protection Unbalance Rate Adjustment Range (%) | Fixed 20% |
| Unbalance Delay Adjustment Range (s) | 2 |
| Phase Sequence Protection | ● |
| Phase Loss Protection | ● |
| PTC Temperature Protection | ○ |
| Load End Protection | - |
| Note | ● indicates this function exists; ○ indicates this function is optional; - indicates no such function. |
