Filter
Top Products
PowerLogic
TM
E4800 Series 930-110-01
Installation 02/2009
© 2009 Schneider Electric All Rights Reserved10
Installing Voltage Transformers for Service
Greater Than 120V
Voltage transformers are required when metering services greater than 120V
to reduce the line-to-neutral voltage of the service to 120V. The accuracy
class should be 0.3% or better, with a burden rating of 30VA.
For applications in Canada, Measurement Canada approved voltage
transformers are required. Measurement Canada requires an accuracy class
of 0.3% or better, with a 150VA rating.
Voltage transformers must be mounted in a listed electrical enclosure. Mount
the voltage transformer enclosure between the supply voltage and the
PowerLogic meters. Transformer configuration must be Y||Y (wye-wye).
Figure 5 shows a block diagram of a complete three-phase 277/480V
installation.
Figure 5: Typical three-phase 277/480V installation
H1
X1
H2 X2
H1
X1
H2 X2
H1
X1
H2 X2
C
B
A
N
N
A
B
C
1
2
3
4
12
Z
5
6
7
8
13
11
12
Shorting block detail
10
9
Legend:
1 Shorting block enclosure
2 Shorting block
3 Breaker panel
4 Current transformer
5 Load breaker
6 Meter breaker
7 Transformer enclosure
8 PowerLogic meter
9 Load
10 Cable
11 Shorting jumper
12 Shorting block
13 DIN rail