AN vs AF Cooling for Dry Type Transformers
Engineering Intent
AN and AF cooling determine how a dry type transformer removes heat under normal and temporary loading conditions.
This article is written for engineers, EPC buyers and procurement teams who need to turn AN and AF cooling selection into a clear technical request instead of a vague product inquiry.
Key Selection Data
| Item | Data to Confirm |
|---|---|
| Check 1 | Base capacity under AN cooling |
| Check 2 | Required overload margin under AF cooling |
| Check 3 | Fan power supply and control wiring |
| Check 4 | Transformer room air inlet and outlet |
Standards and Evidence to Request
- IEC 60076-11
- Project temperature controller specification
- Fan and sensor wiring diagram
For project approval, request a technical datasheet, outline drawing, wiring or terminal diagram where applicable, routine test report and nameplate information before shipment.
Common Specification Mistakes
- Quoting AF capacity without stating AN base rating
- No space for fan maintenance
- No alarm signal integration with building management system
RFQ Checklist
- Confirm AN base kVA
- Confirm whether AF is required
- Specify temperature controller contacts
- Attach room layout if available
Related Product Paths
Ziyao Power can review the single-line diagram, load schedule, panel drawing or tender sheet and convert the requirement into a practical quotation package.
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