S8VK-G
20
Series Operation
Two power supplies can be connected in series.
Note: 1.
The diode is connected as shown in the figure. If the load is
short-circuited, a reverse voltage will be generated inside
the Power Supply. If this occurs the Power Supply may
possibly deteriorate or be damaged. Always connect a
diode as shown in the figure.
Select a diode having the following ratings.
2.
Although Products having different specifications can be
connected in series, the current flowing through the load
must not exceed the smaller rated output current.
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 and 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 (D1, D2) as shown in the
following figure.
•
Use the following information as a guide to the diode type,
dielectric 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.
The parallel operation of S8VK-G is possible to increase the output
power.
However please consider the following notes when the parallel
operation must be done.
1.
The range of ambient temperature for Parallel operation is –25 to
40°C.
2.
Up to two of the same model can be connected in parallel.
3.
Adjust the output voltage difference of each Power Supply to 50
mV or less, using the output voltage adjuster (V. ADJ).
4.
There is no current balancing function for S8VK-G. 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
two Power Supplies balances.
5.
Using the parallel operation will not satisfy UL1310 Class2 output.
6.
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.
7.
If you use the 15-W to 240-W S8VK-G in parallel operation, the
output voltage may drop by several volts if the load changes
rapidly (e.g., if the load starts or is disconnected). If operation
becomes unstable, use the S8VK-R as shown in the diagram.
Refer to the S8VK-R datasheet (Catalog No.: T059) for S8VK-R
specifications and the model number for each capacity.
8.
If you use the 480-W S8VK-G in parallel operation, the output
voltage may drop by several volts if the load changes rapidly (e.g.,
if the load starts or is disconnected). If operation becomes
unstable, connect a diode as shown in the diagram.
•
Use the following information as a guide to the diode type,
dielectric strength, and current.
Type
Schottky Barrier diode
Dielectric strength (V
RRM
) Twice the rated output voltage or above
Forward current (I
F
)
Twice the rated output current or above
Type
Schottky Barrier diode
Dielectric strength (V
RRM
) Twice the rated output voltage or above
Forward current (I
F
)
Twice the rated output current or above
+
V
−
V
+
V
−
V
Correct
AC (L)
AC (
N
)
AC (L)
AC (
N
)
I
N
PUT
+
V
+
V
0
V
−
V
−
V
I
N
PUT
+
V
−
V
Load
Load
I
N
PUT
+
V
D
2
D
1
−
V
I
N
PUT
+
V
−
V
Load
Load
Load
Type
Schottky Barrier diode
Dielectric strength (V
RRM
) Twice the rated output voltage or above
Forward current (I
F
)
Twice the rated output current or above
+
V
−
V
I
N
PUT
S
8V
K-G
S
8V
K-R
S
8V
K-G
I
N
PUT
I
N
1
I
N
2
Load
+
V
−
V
+
V
−
V
+
V
−
V
+
V
−
V
Load
I
N
PUT
I
N
PUT
S
8V
K-G
S
8V
K-G
