For IEEE/ANSI standard transformers, a simple way to communicate the phase shift is to determine how the delta winding is configured. One can look at a phasing diagram for the delta winding and easily determine whether the A-phase delta is delta AB (Ia -Ib) or AC (Ia -Ic) configured. Delta AB shifts the phase angle 30องศา in the positive direction with the delta current leading the wye current. Delta AC shifts the phase angle 30องศา in the negative direction with the delta current lagging the wye current. Using this simple convention, it is possible to communicate the phase shift to a digital relay for IEEE/ANSI standard delta-wye transformers.