S8VK-WA
15
<Making Positive/Negative Outputs>
• The outputs are floating outputs (i.e., the primary circuits and
secondary circuits are separated). You can therefore make
positive and negative outputs by using two Power Supplies. You
can make positive/negative outputs with any of the models.
If positive and negative outputs are used, connect Power Supplies
of the same model as in the following figure. (Combinations with
different output capacities or output voltages can be made.
However, use the lower of the two maximum rated output currents
as the current to the loads.)
• Depending on the model, internal circuits may be damaged due to
startup failure when the power is turned ON if loads such as a
servomotor or operational amplifier may operate in series.
Therefore, connect bypass diodes (D
1
, D
2
) as shown in the
following figure.
• Use the following information as a guide to the diode type, dialectic
strength, and current.
Parallel Operation
Parallel operation is used when the output current from one Power
Supply is insufficient for the load. Power Supplies are connected in
parallel to increase the output current. Two Power Supplies can be
connected in parallel.
You must meet the following conditions to use parallel operation.
• Standard mounting.
• Ambient temperature: -25 to +40°C
• Horizontal separation: 15 mm or more, Vertical separation: 23 mm
or more
• Rated input voltage range and output voltage of 25 V max.
• Adjust the output voltage difference of each Power Supply to 50
mV or less, using the output voltage adjuster (V. ADJ).
• There is no current balancing function for S8VK-X. A high output
voltage unit may work at overcurrent state and in this situation, a
life of a Power Supply will be extremely short. After adjusting the
output voltage, confirm the output current of the Power Supplies
balances.
• For Parallel Operation, to balance the current of the each unit, the
length and thickness of each wire connected to the load and each
unit must be same as much as possible.
• The output voltage may drop by several volts if the load changes
rapidly (e.g., if the load starts or is disconnected). Use the S8VK-R
or connect external diodes as shown in the figure.
For parallel operation with 240-W Power Supplies, use the S8VK-R20.
• Do not use parallel operation when there is the possibility that the
input voltage will vary outside of the rated input range.
• Use the following information as a guide to the diode type, dialectic
strength, and current.
Type
Schottky Barrier diode
Dielectric strength (V
RRM
)
Twice the output voltage or above
Forward current (I
F
)
Twice the rated output current or above
+
V
-
V
+
V
-
V
+
V
0
V
-
V
L1
L2
L3
L1/+
L2
L3/-
L1/+
L2
L3/-
Load
Load
+
V
-
V
+
V
-
V
L1
L2
L3
L1/+
L2
L3/-
L1/+
L2
L3/-
D
2
D
1
Load
Load
Load
Type
Schottky Barrier diode
Dielectric strength (V
RRM
)
Twice the output voltage or above
Forward current (I
F
)
Twice the rated output current or above
+
V
-
V
+
V
-
V
+
V
-
V
L1
L2
L3
L1/+
L2
L3/-
L1/+
L2
L3/-
S
8V
K-R
S
8V
K-
W
A
S
8V
K-
W
A
I
N
1
I
N
2
Load
+
V
-
V
+
V
-
V
L1
L2
L3
D
1
D
2
L1/+
L2
L3/-
L1/+
L2
L3/-
S
8V
K-
W
A
S
8V
K-
W
A
Load
Summary of Contents for S8VK-WA Series
Page 20: ...MEMO 20...
