Siemens UL 1066 Operating Instructions Manual page 157

9.2.2.5 Connecting the voltage transformer
Hazardous voltage.
Will cause death, serious personal injury, or equipment damage.
Turn off and lock out all power supplying this device before working on this device.
The metering module ("MeterPLUS Function") can be set to expect 3W or 4W (LL/LG) connections and will adjust the amplitude and phase
of the signal as necessary.
The parameters on the trip unit must be set as follows:
(1) VT Primary voltage (240 V/480 V/600 V)
(2) VT Secondary voltage
(100 V/110 V/120 V)
VT Connection 
(3)
(Wye / LG, Delta / LL)
Three VTs must be used at all times.
All three VTs must be rated for the rated LL voltage (e.g. 480 V) and can have either 100 V / 110 V or 120 V secondary rated voltage.
primary bus
configuration
Metering VT Settings:
Delta/Wye : Delta
VT Primary: 480 (for instance)
VT Secondary: 120 (for instance)
configuration
Metering VT Settings:
Delta/Wye : Wye
VT Primary: 480 (for instance)
VT Secondary: 120 (for instance)
DANGER
VT primary
connection
V
L-L
primary bus VT primary
connection
(V )/ 3
L-L
3:3W System: Delta (L-L) Connection
Primary
(assuming 480V LL)
L1
V V
L-L 1-2
(480V)
L2
V
2-3
L3
V
3-1
3:4W System: Wye (L-N, L-G) Connection
Primary
(assuming 480V LL)
L1
(V )/ 3
L-L
(277V)
L2
V
L-L
(480V)
L3
LN
Note: Required primary and secondary overcurrent protection (fusing) not shown for clarity.
Secondary
to X8.5
120V
to X8.6
208V
to X8.7
to X8.8
Secondary
to X8.5
(69V)
120V/ 3
to X8.6
120V
to X8.7
69V
to X8.8
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