S8VT
5
Notice
Three phase input operation when one phase is missing
The S8VT will in most cases continue to operate even after the loss
of one phase of the supply. The performance specifications are of
course not guaranteed under these conditions. As the loss of one
phase puts additional stress on some components, the life span of
the unit could be shortened. It is prudent therefore to regularly check
for signs of the following possible conditions.
1.
Input terminals wiring open/loose.
2.
Incorrect/No voltage on one or more phases of the supply.
3
.
Abrupt or periodical loss of input voltage.
The power supply needs output derating as in the chart for the
operation on missing phase at the input voltage range of 340 to
576 V. Otherwise, the power supply may deteriorate or be damaged.
In every single application suitability has to be checked.
Note:
In two phase operation, the specification for EMC
performance, hold-up time, efficiency and output ripple will no longer
be valid.
Three phase input switch off
In order to switch off the Power Supply completely: All 3 phases need
to be switched off.
Mounting
To improve and maintain the reliability of the Power Supply over a
long period, adequate consideration must be taken to heat radiation.
The S8VT is designed to radiate heat by natural air cooling,
therefore, mount the S8VT so that enough air flow takes place
around the power supply.
If installing S8VTF closely, keep the minimum distance of 20 mm at
60°C ambient.
Generating (
±
) Output Voltage
An output of
±
can be generated as shown below, since the S8VT
has a floating output.
Serial Operation
As shown below, the output voltage from each S8VT can be added.
Types must be the same.
Parallel Operation
As shown below, two S8VT-F (same capacity model) can be
paralleled to boost the output power (current). Set the output
voltages of the Power Supplies to the same value.
Also, make sure that the thickness and the length of all wires
connected to the load are the same to ensure that the wires will have
no voltage drop difference.
Parallel connection is only permissible with ambient temperature
from -10°C to +50°C.
In case of a redundant system or back-up system, use diode to be
connected to terminal of all the Power Supplies.
-20 -10
0
10 20
3
0
T
a
(°C)
40 50 60 70
8
0
0
10
20
3
0
40
50
60
Lo
a
d
(
%
)
70
8
0
90
100
110
Mi
ss
in
g
pha
s
e de-ratin
g
S8
VT-F4
8
024E
S8
VT-F96024E
S8
VT-F12024E
S8
VT-F24024E
+ V
−
V
+ V
−
V
Load
Load
+V
−
V
+V
−
V
Load
+ V
−
V
+ V
−
V
Load
M03E-EN-02B+S8VT+Datasheet.fm Seite 5 Montag, 8. Juni 2009 3:35 15