Rugged Environment
AC-DC Converters >100 Watt
KP Series
250 Watt AC-DC Converters with PFC
Input to output isolation
Double output
• Power factor
>0.95,
harmonics
<IEC/EN61000-3-2
• Output power up to 280 Watt
• Input over- and undervoltage lock-out
• Efficient input filter and built-in surge and transient
suppression circuitry
• 4000 V
rms
input to output electric strength test
• Fully isolated outputs
• Outputs open- and short-circuit proof
Safety according to IEC/EN 60950
LGA
C
KP Series
111
4.4"
3U
Summary
The KP series is an extension of the K series of AC-DC con-
verters with an increased output power level of up to 280 W
depending on the operating ambient temperature require-
ments. The KP converters are optimized for use in
230 V AC mains applications and feature high efficiency,
high reliability, low output voltage noise and excellent dy-
namic response to load/line changes.
The converter inputs are protected against surges and tran-
sients occuring at the source lines. An input over- and
undervoltage lock-out curcuitry disables the outputs if the
input voltage is outside the specified range. The LKP types
include an inrush current limitation preventing circuit break-
ers and fuses from being damaged at switch-on.
The outputs are open- and short-circuit proof and are pro-
tected against overvoltages by means of a built-in suppres-
sor diode. The outputs can be inhibited by a logic signal
applied to the connector pin 18 (i). If the inhibit function is
not used pin 18 must be connected with pin 14 to enable
the outputs (fail safe).
LED indicators display the status of the converter and allow
visual monitoring of the system at any time.
80
3.2"
16 TE
168
6.6"
Full input to output, input to case, output to case and output
to output isolation is provided. The modules are designed
and built according to the international safety standards
IEC/EN 60950.
The case design allows operation up to an operating ambi-
ent temperatur of 71°C with reduced output power. De-
pending on the ambient temperature requirements, how-
ever, the output power can be up to 280 W.
An internal temperature sensor generates an inhibit signal
which disables the outputs if the case temperature
T
C
ex-
ceeds the specified limit. The outputs are automatically re-
enabled when the temperature drops below the limit.
Various options are available to adapt the converters to in-
dividual applications. Especially for battery charger applica-
tions an external temperature sensor has been designed to
allow for temperature compensated battery charging.
The modules may either be plugged into 19" rack systems
according to DIN 41494 or be chassis mounted.
Table of Contents
Page
Page
Electromagnetic Compatibility (EMC) ............................ 14
Immunity to Environmental Conditions ........................... 15
Mechanical Data ............................................................ 16
Safety and Installation Instructions ................................ 17
Description of Options .................................................... 20
Accessories .................................................................... 23
Summary .......................................................................... 1
Type Survey and Key Data .............................................. 2
Type Key .......................................................................... 2
Functional Description ...................................................... 3
Electrical Input Data ......................................................... 4
Electrical Output Data ...................................................... 6
Auxiliary Functions ......................................................... 10
MELCHER
The Power Partners.
Edition 4/4.99
1/23
KP Series
Type Survey and Key Data
AC-DC Converters >100 Watt
Rugged Environment
Non standard input/output configurations or special custom adaptations are available on request. See also:
Commercial
Information: Inquiry Form for Customized Power Supply.
Table 1: Type survey
Output
voltage
U
o
[V DC]
24
2
25.25...28.25
2
24, 24
48
3
50.5...56.5
3
1
2
3
4
5
T
A
= 50°C
I
o nom
[A]
11.6
10
5.8, 5.8
5.8
5
U
i min
...U
i max
187...255 V AC
LKP 5661-5R
LKP 5741-5R
4
LKP 5661-5R
LKP 5661-5R
LKP 5741-5R
4
Output current ,input voltage and efficiency
1
h
min
T
A
= 60°C
U
i min
...U
i max
h
min
T
A
= 70°C
[%]
I
o nom
[A]
187...255 V AC [%]
I
o nom
[A]
85
85
85
85
85
10.4
9
5.2, 5.2
5.2
4.5
LKP 5660-6R
LKP 5740-6R
4
LKP 5660-6R
LKP 5660-6R
LKP 5740-6R
4
86
86
86
86
86
9.6
8
4.8, 4.8
4.8
4
Opt.
U
i min
...U
i max
187...255 V AC
LKP 5662-7R
LKP 5742-7R
4
LKP 5662-7R
LKP 5662-7R
LKP 5742-7R
4
h
min
[%]
85
85
85
85
85
E
D
P
5
T
B1
Efficiency at
U
i nom
and
I
o nom
.
Parallel connection of
U
o1
and
U
o2
.
Series connection of
U
o1
and
U
o2
.
Designed for battery charging. Needs external temperature sensor.
Option P not available for LKP 5741-5R, LKP 5740-6R, LKP 5742-7R.
Type Key
Type Key
Input voltage range
U
i
:
187…255 V AC, 47...63 Hz ............................. L
Series ............................................................................ KP
Number of outputs (5 for double outputs) ........................ 5
Nominal voltage output 1
Rectifier version .............................................. 6
Battery charger version ................................... 7
Other specifications .................................... 0...9
Symmetrical double output units:
Nominal voltage output 1/output 2,
U
o1/2 nom
24 V/24 V (48 V series connection) ............... 60
25.25...28.25 V (50.5...56.5 V ser. conn.) ..... 40
other symmetrical voltages .................... 80...99
Operational ambient temperature range
T
A
:
–25…50°C ..................................................... -5
–25…60°C ..................................................... -6
–25…71°C ..................................................... -7
Customer specific ..................................... -0...-4
Auxiliary functions and options:
Output voltage control input ........................... R
Inrush current limitation ................................... E
Potentiometer (output voltage adjustment) ..... P
Save data signal (D0...DD, to be specified) ... D
Current sharing ............................................... T
Cooling plate ................................................. B1
1
L KP 5 6 60 -6 E R P D T B1
1
1
2
2
2
External wiring of main and second output depending upon the desired output configuration (see:
R-Function for different output con-
figurations).
Feature R excludes option P and vice versa. Option P not available for LKP 5740-6R.
LKP
5740-6RD3: Power factor corrected AC-DC converter, input voltage range 187...255 V AC, double out-
put, each providing 25.25...28.25 V/4.5 A, equipped with feature R, undervoltage monitoring option, opera-
tional ambient temperature range –25...60°C.
Example:
MELCHER
The Power Partners.
Edition 4/4.99
2/23
Rugged Environment
Functional Description
AC-DC Converters >100 Watt
KP Series
The input voltage is fed via an input fuse, an input filter, a
rectifier and an inrush current limiter to a single transistor
boost converter. This converter provides a sinusoidal in-
put current (IEC/EN 61000-3-2, class D equipment) and
sources a capacitor with a voltage of 360-370 VDC. This
capacitor sources a single transistor forward converter.
Each output is powered by a separate secondary winding
on the main transformer. The resultant voltages are recti-
fied and their ripples smoothed by a power choke and an
output filter. The control logic senses the main output volt-
age
U
o1
and generates, with respect to the maximum ad-
missible output currents, the control signal for the primary
switching transistor.
The second output is controlled by the main output but has
independent current limiting. If the main output is driven into
current limitation, the second output voltage will fall as well
and vice versa.
P
03002
Forward converter (approx. 80 kHz)
N~ 26
28
1
Y
Boost converter (PFC)
Input filter
Output 1
filter
C
i
+
360 V DC
4
Y
Control circuit
16
18
20
22
R
i
D
T
12 Vo1+
14 Vo1–
4
Vo2+
6
8
Vo2–
10
3
Y
P~ 30
32
Y
24
Y
Output 2
filter
2
Y
–
1
2
3
4
+
Transient suppressor (VDR).
Inrush current limiter (NTC or option E).
Input fuse.
Hold-up capacitor.
Fig. 1
Block diagram of symmetrical double output converters LKP 5000
MELCHER
The Power Partners.
Edition 4/4.99
3/23
KP Series
Electrical Input Data
AC-DC Converters >100 Watt
Rugged Environment
General Conditions
–
T
A
= 25°C, unless
T
C
is specified.
– Pin 18 connected to pin 14,
U
o
adjusted to
U
o nom
(option P); R input not connected.
Table 2: Input data
Input
Characteristics
Conditions
min
187
230
1.25
7
2
480
3200 4000
52.8
EN 55022
U
i nom
,
I
o nom
–400
–400
66
B
B
400
400
V DC
V
P
79.2
µF
10
3
mΩ
A
rms
W
LKP
typ
max
255
Unit
V AC
3
U
i
U
i nom
I
i
P
i o
P
i inh
R
i
R
NTC
C
i
U
i RFI
Operating input voltage
I
o
= 0…I
o nom
T
C min
…
T
C max
Nominal input voltage
Input current
No-load input power
Idle input power
Input resistance
NTC resistance
2
Input capacitance
Conducted input RFI
Radiated input RFI
U
i nom
,
I
o nom 1
U
i min
…
U
i max
unit inhibited
T
C
= 25°C
U
i abs
Input voltage limits
(without damage)
1
2
3
With double output modules, both outputs loaded with
I
o nom
.
Initial switch-on cycle. Subsequent switch-on/off cycles increase the inrush current peak value.
AC frequency range 47...63 Hz.
Input Fuse
A fuse mounted inside the converter protects the module
against severe defects.
Inrush Current Limitation
The modules of the versions -5, -6, -7 incorporate an NTC
resistor in the input circuitry which - at initial turn on - re-
duces the peak inrush current value by a factor of 5...10 to
protect connectors and switching devices from damage.
Subsequent switch-on cycles within short periods will
cause an increase of the peak inrush current value due to
the warming-up of the NTC resistor. See also:
E option.
Inrush Current Peak Value
Table 3: Fuse Specification
Module
LKP 5000
1
1
Fuse type
slow-blow
Fuse rating
SP T
4 A, 250 V
Fuse size 5
×
20 mm
Input Under-/Overvoltage Lock-out
If the input voltage remains below approx. 110 V AC or ex-
ceeds approx. 280 V AC an internally generated inhibit sig-
nal disables the output(s). When checking this function the
absolute maximum input voltage rating
U
i abs
should be
considered! Between
U
i 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).
Input Transient Protection
A VDR together with the input fuse and a symmetrical input
filter form an effective protection against high input tran-
sient voltages.
The inrush current peak value (initial switch-on cycle) can
be determined by following calculation:
U
i rms
•
√2
I
inr p
= ––––––––––––––––
(R
s ext
+
R
i
+
R
NTC
)
04001
R
s ext
I
inr p
R
i
R
NTC
U
i rms
C
i
Fig. 2
Equivalent circuit diagram for input impedance
MELCHER
The Power Partners.
Edition 4/4.99
4/23
Rugged Environment
Input Inrush Current Characteristic
I
inr
[A]
100
AC-DC Converters >100 Watt
Static Input current Characteristic
l
i
[A
rms
]
2
1.5
1
KP Series
04054
04056
50
Û
i
= 360 V
Û
i
= 264 V
0.5
0
175
200
225
250
275
U
i
[V AC]
0 0.1
0.5
1.0
t
[ms]
Fig. 5
Input current versus input voltage at I
o nom
Harmonic Currents
The harmonic distortion is well below the limits specified in
IEC/EN 61000-3-2, class D.
I
i
[mA /W]
0.8
0.7
0.6
Fig. 3
Theoretical input inrush current versus time at
Û
i
= 187 V
•
√
2 (264 V) and 255 V •
√
2 (360 V), R
ext
= 0
Power Factor, Harmonics
Power factor correction is achieved by controlling the input
current waveform synchronously with the input voltage
waveform. The power factor control is active under all oper-
ating conditions.
Power Factor
1
04057
04055
0.5
0.4
0.9
0.3
0.8
U
i
= 255 V AC
U
i
= 187 V AC
0.2
0.1
0
3
5
7
9
11
13
Harm.
0.7
0.6
0
0.2
0.4
0.6
0.8
1
I
o
/I
o nom
Fig. 6
Harmonic currents at the input, IEC/EN 61000-3-2, class D.
U
i
= U
i nom
, I
o
= I
o nom
.
Fig. 4
Power factor versus output power at U
i
255 V AC and
187 V AC.
MELCHER
The Power Partners.
Edition 4/4.99
5/23
