Section IV
Multiple UPS Configurations
006-0006205
UPS-1500 Series
Rev ZC
37 of 60
05/28/2019
Series Split Phase Connection of AC OUTPUTS
Two UPS units can have their AC OUTPUTS connected in series to create an output voltage that
is twice that of the output voltage of the individual UPS units. For instance, if the UPS units each
create an 115Vac output, the series configuration will create a 230Vac output at twice the power
level of a single unit. Or, if the UPS units each create a 230Vac output, the series configuration
will create a 460Vac output at twice the power level of a single unit.
The center node between the two outputs in the series configuration should be considered the
“neutral” wire, and therefore kept at a potential close to Protective Earth Ground (PEGND).
The other two AC OUTPUT wires (one from each UPS unit) are electrically “hot” (meaning at
a high potential relative to the neutral or PEGND). One will be phase- shifted by 180 degrees
(one-half cycle) from the other, meaning that when one hot wire is at its positive peak the other
is at its negative peak, and vice versa. The voltage between these two hot wires is therefore
twice that of either hot wire compared to the neutral wire. This configuration is called “Split
Phase”. When ordering, select the “F: Floating” option for UPS units configured in this manner.
Contact the SynQor factory for N+1 redundant Split Phase systems.
The wiring diagram for the AC OUTPUT cables and the CONFIGURATION cable for the Split Phase
configuration is shown below:
L2
N
PEGND
L1
N
PEGND
AC Output
AC Output
REAR PANEL
REAR PANEL
Line 2
Line 1
L2 L1
N
TO LOAD
PEGND
CONFIGURATION cable SYN-9313
If the user is providing the AC OUTPUT cable, all the cable sections should have the following
minimum wire size, depending on whether the AC OUTPUT of the individual UPS units is 115 Vac
or 230 Vac.
UPS AC Output Voltage
Cable Minimum Wire Size
115 Vac
#14 AWG (2.5 mm
2
)
230 Vac
#16 AWG (1.5 mm
2
)
