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Spike Leg on three phase power

Spike Leg on three phase power

Spike Leg on three phase power

(OP)
What is the "spike leg" on three phase power.  My journeyman said Wye has a spike leg on voltage and Delta has a spike leg on current.  I have not been able to find this with a meter.
I understand that wye is 120/208 etc. or 1.7 times the single leg when any two phases are measured; and delta is double, 110/220.
Is there any truth to the "spike leg" theory?

RE: Spike Leg on three phase power

‘Spike leg’?  New one on me.  Might that be 240V delta or open delta service?  It’s often grounded at the center tap of one of three [or two] 1ø transformers, providing 240V ø-ø, but typically 120V ø-n on A and Cø, and 208V Bø-N.

In that arrangement, Bø is also called stinger/red/orange/purple/power/wild/bastard/high leg.  {There is no particular “spike current” on a wye or delta system unless loads are badly balanced.}
  
http://home.att.net/~benmiller/elecsys.htm has some illustrations of typical US voltage configurations that may help.
  

RE: Spike Leg on three phase power

Suggestion: It is known that wye connection has the voltage configuration that could be viewed as "spiky", namely, Van=Vbn=Vcn=Vab/sqrt3=Vbc/sqrt3=Vca/sqrt3
and delta connection has the current configuration that could be viewed as spiky, namely,
Ia=Ib=Ic=sqrt3 x Iab=sqrt3 x Ibc=sqrt3 x Ica

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