Overview
The JDG4-0.5 indoor dry-type low-voltage potential transformer is a single-phase voltage transformer designed for AC systems rated up to 0.5kV at 50Hz or 60Hz. It converts primary system voltage into a standardized 100V secondary signal for use with measuring instruments, energy meters, and relay protection devices.
Built with a dry-type C-core structure, the JDG4-0.5 features primary and secondary windings mounted on the center limb of a high-quality silicon steel core. It is ideal for integration into low-voltage switchgear, metering panels, distribution cabinets, and power monitoring systems requiring accurate voltage signals for metering, control, and protection.
Key Ratings Snapshot
| Parameter | Value |
|---|---|
| Rated voltage class | 0.5kV and below |
| Primary voltage range | 100V to 1140V |
| Secondary voltage | 100V (standard) |
| Rated frequency | 50Hz / 60Hz |
| Accuracy class | 0.5 |
| Rated output | 15VA |
| Limit output | 100VA |
| Insulation voltage | 3kV |
| Power-frequency withstand | 3000V / 1min |
| Installation location | Indoor |
Model Designation
- J: Voltage transformer
- D: Single-phase structure
- G: Dry-type design
- 4: Design series code
- 0.5: Rated voltage class: 0.5kV
Construction
The JDG4-0.5 employs an indoor dry-type construction with no oil insulation, making it safe and maintenance-free for enclosed environments. Its core is fabricated from cold-rolled silicon steel sheets formed into a C-type magnetic circuit, ensuring low losses and stable performance under load.
Windings are precisely wound and encapsulated for electrical isolation and mechanical stability. The compact housing includes fixed mounting provisions suitable for panel or cabinet installation, supporting reliable operation in metering and protection applications.
Technical Parameters
Service Conditions
- Installation location: Indoor
- System voltage: <= 0.5kV
- Rated frequency: 50Hz / 60Hz
- Ambient temperature: -25 degC to +40 degC
- Altitude: <= 1000m (unless specified otherwise)
- Environment: No rain, snow, direct outdoor exposure, severe pollution, or strong vibration
Technical Data
| Model | Rated Voltage Ratio |
Rated Frequency |
Accuracy Class |
Rated Output (VA) |
Limit Output (VA) |
Rated Insulation Voltage (kV) |
|---|---|---|---|---|---|---|
| JDG4-0.5 | (100-1140)V / 100V | 50-60Hz | 0.5 | 15 | 100 | 3 |
Installation & Wiring
Installation Diagram
The JDG4-0.5 uses a fixed base mounting structure suitable for indoor cabinet installation. Always refer to the approved dimensional drawing before panel cutout, wiring, or batch deployment to ensure compatibility with enclosure layout and terminal access.
Outline Dimensions
| Model | Structure | Installation Method | Dimension Reference |
|---|---|---|---|
| JDG4-0.5 | Indoor dry-type C-core | Base fixed installation | Per approved drawing (unit: mm) |
Selection & FAQs
Selection Guide
- Specify the exact primary and secondary voltage. Do not order only by model code when using the broad 100V–1140V / 100V–230V customization range.
- Keep the accurate burden within 15VA. Add meter or relay input, wiring and protective-device burden for the complete secondary circuit.
- Do not use 100VA as a class 0.5 rating. It is limiting thermal output; measurement accuracy is specified only at the rated 15VA burden.
- Reconfirm insulation above 500V. The “0.5” suffix and 3kV/1min reference do not by themselves establish suitability for every 1140V application.
- Approve the cabinet interface. Confirm A/X and a/x terminals, fusing, grounding, base holes, ventilation, clearances and the final drawing for the customized ratio.
Frequently Asked Questions
Q1: What is the maximum system voltage for this potential transformer?
It is designed for low voltage systems up to 0.5kV, featuring a 3kV rated insulation voltage. For higher voltage requirements, contact our engineering team for alternative models.
Q2: Can the JDG4-0.5 be installed in outdoor environments?
No, this is strictly an indoor dry-type transformer. It must be installed in locations free from rain, snow, severe pollution, and strong vibrations to ensure optimal performance.
Q3: Which accuracy class does this low voltage PT provide?
The standard JDG4-0.5 model offers a 0.5 accuracy class with a 15VA rated output. Custom accuracy classes can be arranged subject to technical agreement and factory confirmation.
Q4: Can the rated voltage ratio be customized for specific projects?
Yes, primary and secondary voltage ratios can be customized per your technical agreement. Final parameters will be strictly subject to the approved nameplate data and specifications.
Q5: Are custom frequency ratings available for this potential transformer?
Yes, it supports both 50Hz and 60Hz rated frequencies natively. If your project requires specific frequency validations, please provide detailed technical specifications for factory review.
Q6: What applications is the JDG4-0.5 dry-type transformer suitable for?
It is ideal for indoor low voltage switchgear and power distribution panels up to 0.5kV. Contact us to verify if this model matches your specific panel design requirements.