Specifications

Connecting two or more power
supplies in series (Figure 1) pro-
vides higher voltages, but observe
these precautions:
• Never exceed the floating volt-
age rating of any of the supplies.
• Never subject any of the power
supplies to negative voltages.
Program each power supply inde-
pendently. If two supplies are
used, program each one for 50%
of the total output voltage. If three
supplies are used, program each
supply for about 33% of the total
output voltage. Set the current
limit of each supply to the maxi-
mum that the load can safely
handle.
Connecting two or more power
supplies in parallel (Figure 2) pro-
vides higher currents, but again,
observe these precautions:
• One unit must operate in con-
stant voltage (CV) mode and the
other(s) in constant current
(CC) mode.
• The output load must draw
enough current to keep the CC
unit(s) in CC mode.
Program the current limit of each
unit to its maximum value and pro-
gram the output voltage of the CV
unit to a value slightly lower than
the CC unit(s). The CC units sup-
ply the maximum output current
that they have been set to and
drop their output voltage until it
matches the voltage of the CV unit,
which supplies only enough cur-
rent to fulfill the total load
demand.
Connect Power Supplies
in Series or Parallel for
Higher Output
Tip
7
Power Supply
# 1
Power Supply
# 1
Power Supply
# 1
E
M
E
1
E
2
E
L
R
L
E
L
=E
M
+E
1
+E
2
I
L
Power Supply
# 1
I
M
I
L
=I
M
+I
1
+I
2
Power Supply
# 2
Power Supply
# 3
I
1
I
2
R
L
Figure 1: Connecting units in series.
Figure 2: Connecting units in parallel.
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