Indoor Instrument Transformer Epoxy Insulation Guide
Engineering Intent
Epoxy insulation is widely used for indoor CTs and VTs, but creepage, humidity and switchgear environment should still be reviewed.
This article is written for engineers, EPC buyers and procurement teams who need to turn epoxy insulated instrument transformer into a clear technical request instead of a vague product inquiry.
Key Selection Data
| Item | Data to Confirm |
|---|---|
| Check 1 | Indoor environment |
| Check 2 | System voltage and insulation level |
| Check 3 | Panel compartment condition |
| Check 4 | Creepage and clearance requirement |
Standards and Evidence to Request
- IEC 61869
- Switchgear insulation coordination
- Routine dielectric test
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
- Ignoring humidity and pollution class
- No insulation level in RFQ
- Poor terminal access after installation
RFQ Checklist
- State system voltage
- Confirm indoor conditions
- Request insulation level data
- Share panel drawing
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.
Download This Guide as PDF
Save this technical guide for offline reference. Includes all tables, specifications, and contact information.
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