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9.2.2.5 Connecting the voltage transformer
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)
(3) VT Connection
(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.
DANGER
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.
Note: Required primary and secondary overcurrent protection (fusing) not shown for clarity.
to X8.8
to X8.7
to X8.6
to X8.5L1
L2
L3
LN
120V/ 3
primary bus
configuration
VT primary
connection
VT primary
connection
3:4W System: Wye (L-N, L-G) Connection
Secondary
to X8.8
to X8.7
to X8.6
to X8.5
L1
L2
L3
V
1-2
120V
V
2-3
V
3-1
Primary
V
L-L
(V
L-L
)/ 3
(V
L-L
)/ 3
V
L-L
3:3W System: Delta (L-L) Connection
SecondaryPrimary
(assuming 480V LL)
(277V)
(69V)
(assuming 480V LL)
(480V)
208V
V
L-L
(480V)
120V
Metering VT Settings:
Delta/Wye : Delta
VT Primary: 480 (for instance)
VT Secondary: 120 (for instance)
Metering VT Settings:
Delta/Wye : Wye
VT Primary: 480 (for instance)
VT Secondary: 120 (for instance)
primary bus
configuration
69V