26
Rockwell Automation Publication 1606-RM028A-EN-P - September 2021
Series Operation
Earthing of the output is required when the sum of the output voltage is above
60V DC.
Avoid return voltage (for example, from a decelerating motor or battery) which
is applied to the output terminals.
Keep a left and right installation clearance of 15 mm (0.59 in.) between two
power supply units and avoid installing the units on top of each other. Do not
use power supply units in series in mounting orientations other than the
standard mounting orientation (terminals on the bottom of the unit).
Understand that leakage current, EMI, inrush current, and harmonics
increase when using multiple power supply units.
Operation on Two Phases
Figure 46 - Series Operation
Power supplies of the same type can
be connected in series for higher
output voltages. Connect as many
units in series as needed, providing
the sum of the output voltage does
not exceed 150V DC. Voltages with
a potential above 60V DC can be
dangerous and are no longer SELV.
Such voltages must be installed
with a protection against being
touched.
Unit A
AC
DC
Unit B
AC
DC
-
+
-
+
Load
+
-
Earth
Figure 47 - Operation on Two Phases
The power supply unit can be used
on two phases of a three-phase
system, as long as the supplying
voltage is below 240V
+10%
.
240V
+10%
max
L2
L1
L3
L
N
PE
Power Supply
AC
DC
internal
fuse
