Cassette Style
AC-DC Converters
K Series
Edition 5/5.2000
4/26
Static Input Current Characteristic
2
345
6
1
1.00
Ui DC
_______
Ui min DC
Ii (A)
3.00
0.40
04048
Fig. 4
Input current versus relative input voltage
Input Fuse
A fuse mounted inside the converter protects the module
against severe defects. If operated from a DC source this
fuse may not fully protect the module when the input volt-
age exceeds 200 V DC! In applications where the convert-
ers operate at source voltages above 200 V DC an external
fuse or a circuit breaker at system level should be installed!
Table 3: Fuse Specification
Module
Fuse type
Fuse rating
LK 1
slow-blow
SPT
4 A, 250 V
1 Fuse size 5
× 20 mm.
Input Under-/Overvoltage Lock-out
If the input voltage remains below approx. 0.8
Ui min or ex-
ceeds approx. 1.1
Ui max
nal disables the output(s). When checking this function the
absolute maximum input voltage rating
Ui abs should be
considered! Between
Ui min and the undervoltage lock-out
level the output voltage may be below the value defined in
table:
Output data (see: Technical Information: Measuring
and Testing).
Reverse Polarity Protection
The built-in bridge rectifier provides reverse polarity protec-
tion at the input.
Inrush Current Limitation
The modules of the versions -7 incorporate an NTC resistor
in the input circuitry which – at initial turn on – reduces the
peak inrush current value by a factor of 5...10 to protect
connectors and switching devices from damage. Subse-
quent switch-on cycles within short periods will cause an
increase of the peak inrush current value due to the warm-
ing-up of the NTC resistor. (see also:
option E)
Inrush Current Peak Value
The inrush current peak value (initial switch-on cycle) can
be determined by following calculation: (See also:
Input In-
rush Current Characteristic).
Ui source
Iinr p = ––––––––––––––––
(
Rs ext + Ri + RNTC)
Rs ext
Ri
RNTC
Iinr p
Ui source
+
Ci int
04040
Fig. 3
Equivalent circuit diagram for input impedance
Electrical Input Data
General Conditions
–
TA = 25
°C, unless T
C is specified.
– Pin 18 connected to pin 14,
Uo adjusted to Uo nom (option P); R input not connected.
– Sense line pins S+ and S– connected to Vo+ and Vo– respectively.
Table 2: Input data
Input
LK
Characteristics
Conditions
min
typ
max
Unit
Ui
Operating input voltage
Io = 0…Io nom
85
264
V AC
TC min…TC max
88
372
V DC
Ui nom Nominal input voltage
310
3
Ii
Input current
Ui nom, Io nom 1
0.4
A
Pi0
No-load input power
Ui min…Ui max
2.5
W
Pi inh
Idle input power
unit inhibited
1.5
Ri
Input resistance
TC = 25°C
480
m
RNTC
NTC resistance 2
3200
Ci
Input capacitance
210
400
F
Ui RFI
Conducted input RFI
EN 55022
B
Radiated input RFI
Ui nom, Io nom
B
Ui abs
Input voltage limits
–400
400
V DC
without damage
–400
400
Vp
1 With double output modules, both outputs
loaded with
Io nom
2 Valid for -7 versions with NTC, (-9 versions ex-
clude the NTC). Initial switch-on cycle. Subse-
quent switch-on/off cycles increase the inrush
current peak value.
3 LK types may also be operated in DC mode.
(See:
K Series, DC-DC Converters)
AC frequency range 47...440 Hz (440 Hz
for 115 V mains).
Above 70 Hz (at
Ui = 264 V AC) the earth
lekage current may exceed 3.5 mA, speci-
fied in IEC/EN 60950. The built-in Y ca-
pacitors are specified for
≤100 Hz. Above
350 Hz the input voltage may not exceed
200 V AC.