DIN 42531 20NF250A Transformer Bushing Isolators
High Voltage Transformer Bushings
Product Overview
A DIN 42531 bushing in the 20NF250A pattern for the 20 kV class at 250 A, connecting transformers and generators to high voltage transmission lines. The porcelain shell, iron core and conductor combination resists high pressure, high temperature, arc and dirt. The shell is alumina and mica ceramic, the core silicon steel sheet and the conductor electrolytic copper or aluminium alloy.
- DIN 42531
Key benefits
Why Buyers Choose This Part
- DIN 42531 20NF pattern for 20 kV terminal boards
- Silicon steel sheet core to cut hysteresis and iron loss
- Alumina and mica shell combining insulation and mechanical strength
- Electrolytic copper or aluminium alloy conductor for excellent conductivity
Application scenarios
Where It Is Used
- 20 kV transformer and generator connections to transmission lines
- Distribution transformer manufacture to DIN patterns
- Replacement of 20NF250A bushings during overhaul
- Terminal boards where the DIN dimensional pattern is fixed
Who it is for
Who It Suits
- Transformer manufacturers working to DIN 42531
- Generator package builders at 20 kV
- Distributors supplying the DIN NF series
Problems it solves
What Goes Wrong Without The Right Part
- Terminal boards that will only accept the DIN dimensional pattern
- Core and conductor losses under continuous load
- Shell degradation from arc, heat and airborne dirt
- Supply delays on 20NF pattern replacement parts
Technical features
How It Is Built
- DIN 42531 20NF250A pattern
- 20 kV class at 250 A
- Porcelain shell of alumina and mica ceramic
- Silicon steel sheet iron core
- Electrolytic copper or aluminium alloy conductor
- Resistance to high pressure, high temperature, arc and dirt
Specifications
Published Figures For This Product
Every value below comes from the manufacturer data for this item. Figures not listed are confirmed against the drawing before an order is placed.
| DIN 42531 20NF Pattern | 250 A |
|---|
Materials
Materials
- Alumina and mica ceramic shell
- Silicon steel sheet core
- Electrolytic copper or aluminium alloy conductor
Manufacturing
Process
- Shell forming
- Glazing
- Firing
- Core and conductor assembly
- Inspection and testing
Quality control
Testing
- Strict inspection and testing before despatch
- Conductor conductivity and contact verification
- Shell and glaze integrity inspection
Certifications
Certification
- Manufactured to DIN 42531
- ISO 9001 quality management system
Customisation
Customisation Options
- Special lengths and screw sizes to specification
- Conductor metal matched to your connection
- OEM and ODM marking
Comparison
How It Compares
| DIN 20NF250A CD480 | The CD480 listing publishes a 480 mm creepage, 50 kV power frequency withstand and 125 kV lightning impulse withstand for the same 20NF250A family. |
|---|---|
| DIN 42531 30NF250A | Same standard and current rating at the 36 kV class. The NF number sets the voltage, so match it to the transformer. |
Use guide
Before You Order And After It Arrives
- Confirm your drawing quotes DIN 42531 and the 20NF number
- Inspect and test before installation as the standard requires
- Apply protective grounding and lightning protection
- Match the conductor metal to your connection lugs
Questions
DIN 42531 20NF250A Transformer Bushing Isolators Questions
What voltage and current is the 20NF250A?
The 20 kV class at 250 A.
What standard applies?
DIN 42531.
What is the shell made of?
Ceramic materials such as alumina and mica, which combine good insulation performance with mechanical strength.
What creepage distance does this family give?
The companion CD480 listing publishes 480 mm creepage with 50 kV power frequency withstand and 125 kV lightning impulse withstand.
Why is the core silicon steel?
To reduce hysteresis loss and iron loss and improve energy utilisation efficiency.
Can you produce to our drawing?
Yes, including special lengths and different screw sizes.
Related
Related Products
EN 36/250/P3 Transformer Bushing Insulator 36kV
- Voltage 36 kV
- Height 600 mm
- Diameter 155 mm
24kV Porcelain Transformer Bushing 150kV BIL
- Wet Power Frequency Withstand Voltage 60 kV
- Net Weight Per Bushing 8 kg
- Height 453 mm
DIN 20NF630A Transformer Bushing 440mm Creepage
- Nominal Creepage Distance 440 mm
- Net Weight 6.1 kg
- Height 385 mm
DIN 24kV 630A Transformer Bushing CD525
- Creepage Distance 525 mm
- Net Weight 6.8 kg
- Height 385 mm
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Quote For DIN 42531 20NF250A Transformer Bushing Isolators
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