Current Transformer Burden Calculation
Engineering Intent
CT burden must include meter or relay load plus secondary cable resistance to maintain accuracy.
This article is written for engineers, EPC buyers and procurement teams who need to turn CT burden calculation into a clear technical request instead of a vague product inquiry.
Key Selection Data
| Item | Data to Confirm |
|---|---|
| Check 1 | Meter or relay VA load |
| Check 2 | Secondary cable length and cross-section |
| Check 3 | Secondary current 1A or 5A |
| Check 4 | Required accuracy class |
Standards and Evidence to Request
- IEC 61869 burden references
- Relay and meter datasheets
- Panel wiring schedule
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 cable resistance
- Using 5A secondary for long cable runs without checking burden
- No VA value in RFQ
RFQ Checklist
- List connected devices
- State cable length
- Confirm secondary current
- Request burden compliance
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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