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2017 Sensata Technologies
Page 23
Installation
2.3.6.2
Connecting the MS-PAE Directly
If an isolation transformer is not available, as an alternative option, part of the three-phase source
can be connected directly. This is done by connecting only one phase to neutral from the three-
phase source to one of the inputs to neutral on the MS-PAE inverter, as shown in Figure 2-11. Even
though you are only providing 120 VAC—by using only one of the three phases to neutral—the
inverter will continue to provide 120/240 VAC on the output because of the step-up transformer
design inside the inverter.
Info:
If providing only 120 volts to the inverter input, the charger must be turned down
to 50% to prevent overheating from occurring.
Figure 2-11, Connecting the MS-PAE Directly to Three-Phase Power
3-PHASE WYE
NEUTRAL
120
VAC
A
B
C
MS-PAE SERIES
H1 IN
N IN
H1 OUT
H2 IN
H2 OUT
N OUT
120
VAC
120
VAC
240
VAC
Figure 2-10, Connecting the MS-PAE to Three-Phase Power using a
Buck-Boost Transformer
STEP-UP ISOLATION
TRANSFORMER
208
VAC
3-PHASE WYE
NEUTRAL
A
B
C
MS-PAE SERIES
H1 IN
N IN
H1 OUT
H2 IN
H2 OUT
N OUT
120
VAC
120
VAC
240
VAC
NEUTRAL
120
VAC
120
VAC
2.3.6.1
Connecting the MS-PAE using a Buck-Boost Transformer
A buck-boost transformer is designed to decrease (buck) or increase (boost) line voltage. As shown
in Figure 2-10, to connect to the MS-PAE input, the buck-boost transformer must be capable of
connecting 208 VAC on the primary side and step-up (or boost) to 240 VAC on the secondary side.
This transformer must include a center-tapped connection on the secondary side to provide both
120 and 240 volts to the MS-PAE inverter, and must have the primary winding isolated from the
secondary winding to ensure there is no phase mismatch.
Links to some transformer manufacturers are listed below:
www.acmetransformer.com
www.hamondpowersolutions.com
