Instruction Manual

www.schaeferpower.de
Options & Accessories Options & Accessories
for Switch Mode Units
Options & Accessories
Schaefer offers the industry’s most
complete range of input and output
voltages, combined with a selection
of package style, mounting solutions,
options for input and output as well as
various possibilities of programming &
monitoring.
Configuration of model designation:
Add the designation of options to
the type number of the power supply
module, e.g. C 3674-w-dr-eu1.
Input
i inrush current limiting
A thermistor is connected in series with the input lines which changes its resistance from
high to low when it gets hot. It does not reduce the surge current if the input power
is interrupted for a short period of time not allowing the thermistor to cool down.
Thermistors are fitted as standard to all mains input models except for 1-phase input
of models > 2.5 kW. Thermistors are available up to 45A. For higher input current an
electronic inrush current limitation can be offered.
ie electronic inrush current limiting
An electronic circuit limits the high inrush current caused by built-in capacitors. Switch-
on time may increase to 5s.
This is realized by a series pass transistor or depending on the input voltage by thyristor
softstart.
sd reverse polarity protection for DC input by series diode
A series diode protects the module against DC input voltage of wrong polarity. However,
this also causes extra losses and reduces the overall efficiency.
calculation formula: I
Diode
= 2 x P
out max
/ U
in min
ad reverse polarity protection for DC input by anti parallel diode
To avoid the power losses a diode is provided with opposite polarity in parallel to the
input blowing an internal or external fuse if the module is connected to a supply of wrong
polarity.
calculation formula: I
Diode
= 2 x P
out max
/ U
in min
au auto-ranging
For standard dual AC input models the range of 115 / 230 V AC is to be selected by
connecting the input line to different pins on the connector. With auto-ranging the unit
senses the input voltage and provides automatically the correct connection.
OUTIN
OUTIN
time
delayed
IN OUT
OUT
L
N
1
15V AC
o
r
2
30V AC
OUT
IN