Overview
5
Single-Phase Three-Wire
This is seen in residential and commercial service with 240 VAC for large appliances. The three wires are
neutral and two line voltage wires with AC waveforms 180° out of phase. This results in 120 VAC
between either line wire and neutral, and 240 VAC (or sometimes 208 VAC) between the two line wires.
Any unused CT inputs must be shorted with an insulated jumper wire. Single-phase three-wire circuits
should be measured with models WNA-1P-240-P or WNA-3Y-208-P.
Neutral
Phase A
LINE
Phase B
LOAD
Current
Transformers
WHITE
BLACK
Source
Faces
WHITE
BLACK
Neutral
Output
WNA-1P-240-P
Continental Control Systems
W
ATT
N
ODE
B CT
A CT
B 120 VAC
A 120 VAC
Figure 2: One-Phase Three-Wire Connection
