ZEFNET Pro User Manual
15
Figure 5: 240V 3-Phase, Delta-Connected, with Center-Tap on One Leg
CAUTION
: With the delta connection, one leg
must
be center-
tapped.
Only
the two phases on either side of the center tap can
be used. The two phases
must both
measure 120V to Neutral.
The third line (L3) of the delta is 208V, with respect to Neutral,
and is sometimes referred to as a “stinger” or “wild leg”.
Do not
use this third line!
Consult the transformer manufacturer’s
literature to be sure the single leg can supply the required power.
CAUTION
: A 3-phase delta-connected transformer secondary
without a center-tap on one leg
cannot be used with the ZEFNET
Pro
. No “Neutral” point is available to be connected to ground for
ground-fault protection. The ZEFNET Pro will not allow the
