Vector Group Designations
The complete system of winding configuration codes for three-phase transformer system integration.
Vector group designations encode: HV connection, LV connection (+ neutral), phase displacement as clock number.
Common: Dyn11 (distribution—HV delta, LV star N, 330-degree lead); Yyn0 (small distribution, in phase); YNd11 (power—HV star N, LV delta, 330-degree); Dd0 (industrial); Yz5/11 (zig-zag—grounding).
Clock: each = 30 degrees. 0=0deg, 11=330deg. Determines parallel compatibility, harmonics, fault characteristics.
QDTB manufactures all configurations with engineering support for selection. See selection guide for guidance.
Related Products
Related Terms
Vector Group
Standardized designation of transformer winding connections and phase displacement between HV and LV.
Three-Phase Transformer
A transformer for three-phase power systems with three winding sets on a common core.
Neutral Point
The common connection point of a star (wye) winding where the three-phase voltage vector sum equals zero.
Wye-Delta Connection
A three-phase connection with one star and one delta winding providing phase shift and harmonic isolation.
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Altitude Derating
The reduction in transformer capacity and insulation performance required at high altitudes where air density is lower.
Cooling Class (ONAN/ONAF/ODAF)
Standardized codes describing transformer cooling methods: O=Oil, N=Natural, A=Air, F=Forced, D=Directed flow.
Faraday Shield
An electrostatic shield between transformer windings blocking capacitive coupling of high-frequency noise.
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