Puls QS10.241-60, Dimension Q-Series User Manual

QS10.241-60

Q-Series

24V, 200W, DC/DC CONVERTER

DC/DC CONVERTER

 EN 50155 Railway Compliant
 Conformal Coated PC-boards
 Quick-connect Spring-clamp Terminals
 77-154Vdc Wide-range Input
 Width only 60mm
 Efficiency up to 93.0%
 Excellent Partial Load Efficiency
 Minimal Inrush Current Surge
 Full Power Between -40°C and +70°C
 DC-OK Relay Contact
 Reverse Input Polarity Protected
 3 Year Warranty

1/27

GENERAL DESCRIPTION

The QS10.241-60 DC/DC converter is designed
specifically for railway & transportation applications. It
is approved according to the EN 50155 standard, which
is an international standard covering electronic
equipment used on rolling stock for railway
applications. The standard covers aspects such as
temperature, humidity, shock, vibration, EMI and other
parameters. Because of these requirements, the unit is
equipped with conformal coated pc-boards.

The unit features a DC-OK signal contact for remote
monitoring, and quick-connect spring-clamp terminals
for a reliable connection even when mechanical
vibration and shock are involved. The unit also covers an
extreme wide temperature range from -40°C up to
+70°C with full output current.

This DC/DC converter comes in a very compact housing
and requires only 60mm space on the DIN-rail due to
the high efficiency and low power losses. The high
efficiency is achieved by utilizing cutting edge
technology and other unique design techniques.

SHORT-FORM DATA

Output voltage DC 24V
Adjustment range 24 - 28V
Output current 8.3 – 7.1A continuous

12.5 – 10.7A for typ. 4s
Output power 200W continuous
300W for typ. 4s
Output ripple max. 50mVpp 20Hz to 20MHz
AC Input voltage - ­DC Input voltage DC 110V - 30%/ +40%
DC Input current 1.96A at 110Vdc
Inrush current typ. 4A peak at 110Vdc
Efficiency 93.0% at 110Vdc
Losses 15.0W at 110Vdc
Temperature range -40°C to +70°C operational
Derating - not required
Hold-up time typ. 23ms at 110Vdc
Dimensions 60x124x117mm WxHxD
Weight 920g / 2.03lb

ORDER NUMBERS

DC/DC converter QS10.241-60

Accessory ZM13.SIDE Side mount bracket
YR2.DIODE Redundancy module
UF20.241 Buffer module

MARKINGS

EMC, LVD

Aug. 2016 / Rev. 1.0 DS-QS10.241-60-EN
All parameters are specified at 24V, 8.3A, 110Vdc, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.

www.pulspower.com Phone [phone] Germany

QS10.241-60

Q-Series

24V, 200W, DC/DC CONVERTER

INDEX

Page Page

1.

Intended Use .......................................................3

2. Installation Requirements...................................3

3. AC-Input...............................................................4

4. DC-Input...............................................................4

5. Input Inrush Current ...........................................5

6. Output .................................................................6

7. Hold-up Time.......................................................8

8. DC-OK Relay Contact ..........................................9

9. Efficiency and Power Losses..............................10

10. Lifetime Expectancy and MTBF.........................10

11. Functional Diagram...........................................11

12. Terminals and Wiring........................................12

13. Front Side and User Elements...........................13

14. EMC....................................................................14

15. Environment......................................................15

16. Protection Features ...........................................16

17. Safety Features ..................................................16

18. Dielectric Strength ............................................17

19. Approvals and Declarations..............................18

20. RoHS, REACH and Other Fulfilled Standards .. 18

21. Physical Dimensions and Weight..................... 19

22. Accessories ........................................................ 20

22.1. ZM13.SIDE - Side Mounting Bracket........20

22.2. UF20.241 Buffer Module .......................... 20

22.3. YR2.DIODE Redundancy Module.............21

23. Application Notes............................................. 22

23.1. Repetitive Pulse Loading..........................22

23.2. Peak Current Capability ...........................23

23.3. Inductive and Capacitive Loads................23

23.4. External Input Protection.........................24

23.5. Charging of Batteries ...............................24

23.6. Parallel Use to Increase Output Power....24

23.7. Parallel Use for Redundancy .................... 25

23.8. Series Operation .......................................25

23.9. Back-feeding Loads ..................................26

23.10. Use in a Tightly Sealed Enclosure ............26

23.11. Mounting Orientations ............................27

The information presented in this document is believed to be accurate and reliable and may change without notice.
No part of this document may be reproduced or utilized in any form without permission in writing from the publisher.

TERMINOLOGY AND ABREVIATIONS

PE and symbol PE is the abbreviation for Protective Earth and has the same meaning as the symbol .

Earth, Ground This document uses the term “earth” which is the same as the U.S. term “ground”.

T.b.d. To be defined, value or description will follow later.

DC 110V A figure displayed with the AC or DC before the value represents a nominal voltage with

standard tolerances (usually ±15%) included.
E.g.: DC 12V describes a 12V battery disregarding whether it is full (13.7V) or flat (10V)

110Vdc A figure with the unit (Vdc) at the end is a momentary figure without any additional

tolerances included.

may A key word indicating flexibility of choice with no implied preference.

shall A key word indicating a mandatory requirement.

should A key word indicating flexibility of choice with a strongly preferred implementation.

Aug. 2016 / Rev. 1.0 DS-QS10.241-60-EN
All parameters are specified at 24V, 8.3A, 110Vdc, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.

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2/27

QS10.241-60

Q-Series

24V, 200W, DC/DC CONVERTER

1. INTENDED USE

This device is designed for installation in an enclosure and is intended for the general professional use such as in
rolling stock for railway applications or in industrial control, office, communication, and instrumentation equipment.

Do not use this DC/DC converter in equipment, where malfunction may cause severe personal injury or threaten
human life.

2. INSTALLATION REQUIREMENTS

This device may only be installed and put into operation by qualified personnel.
This device does not contain serviceable parts. The tripping of an internal fuse is caused by an internal defect.
If damage or malfunction should occur during installation or operation, immediately turn power off and send unit to

the factory for inspection.
Mount the unit on a DIN-rail so that the input terminals are located on the bottom of the unit. For other mounting

orientations see de-rating requirements in this document. See chapter 23.11.
This device is designed for convection cooling and does not require an external fan. Do not obstruct airflow and do

not cover ventilation grid (e.g. cable conduits) by more than 15%!
Keep the following installation clearances: 40mm on top, 20mm on the bottom, 5mm on the left and right sides are

recommended when the device is loaded permanently with more than 50% of the rated power. Increase this clearance
to 15mm in case the adjacent device is a heat source (e.g. another power supply).

WARNING

Risk of electrical shock, fire, personal injury or death.

- Do not use the DC/DC converter without proper grounding (Protective Earth). Use the terminal on the input block
for earth connection and not one of the screws on the housing.

- Turn power off before working on the device. Protect against inadvertent re-powering.

- Make sure that the wiring is correct by following all local and national codes.

- Do not modify or repair the unit.

- Do not open the unit as high voltages are present inside.

- Use caution to prevent any foreign objects from entering the housing.

- Do not use in wet locations or in areas where moisture or condensation can be expected.

- Do not touch during power-on, and immediately after power-off. Hot surfaces may cause burns.

Aug. 2016 / Rev. 1.0 DS-QS10.241-60-EN
All parameters are specified at 24V, 8.3A, 110Vdc, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.

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3/27

QS10.241-60

Q-Series

24V, 200W, DC/DC CONVERTER

3. AC-INPUT

Do not operate this DC/DC converter with an AC-input voltage. Use the QS10.241 or QS10.241-C1 unit instead.

4. DC-INPUT

Use a battery or a similar DC source. A supply from the intermediate DC-bus of a frequency converter is not
recommended and can cause a malfunction or damage the unit.

Input voltage nom. DC 110V -30%/+40%
Input voltage range 77-154Vdc
66-77Vdc short term for 100ms
Input current typ. 1.96A at 8.3A and 110Vdc input voltage, see Fig. 4-3
Allowed voltage between input

to earth (ground)

max. 375Vdc continuous, IEC 62103

± 600V peak value, allowed for transients
Slew rate for voltage between

input to earth (ground)

max. 1000V/μs

Allowed input ripple voltage max. 15Vpp

3Vpp

50Hz –10kHz
10kHz – 50kHz

Turn-on voltage typ. 71Vdc steady-state value, at ambient temperatures between

-40°C and +70°C, see Fig. 4-1
Shut-down voltage typ. 61Vdc steady-state value, see Fig. 4-1
Start-up delay typ. 500ms see Fig. 4-2
Rise time typ. 20ms at 8.3A constant current load, 0mF load capacitance,

see Fig. 4-2

typ. 45ms at 8.3A constant current load, 8mF load capacitance,

see Fig. 4-2
Turn-on overshoot max. 200mV see Fig. 4-2
External input protection See recommendations in chapter 23.4.

Fig. 4-1 Input voltage range Fig. 4-2 Turn-on behavior, definitions

Turn-on

77V

Rated

input range

max.

500ms

V

IN

P

OUT

375Vdc154V

Shut-down

Start-up

delay

Rise

Time

Overshoot

- 5%

Output
Voltage

Input
Voltage

Aug. 2016 / Rev. 1.0 DS-QS10.241-60-EN
All parameters are specified at 24V, 8.3A, 110Vdc, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.

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4/27

QS10.241-60

Q-Series

24V, 200W, DC/DC CONVERTER

Fig. 4-3 Input current vs. output load at 24V

output voltage

8

01234

0

0.5

1.0

1.5

2A

Output Current

Input Current at 110Vdc input, typ.

567

9A

5. INPUT INRUSH CURRENT

An active inrush limitation circuit limits the input inrush current after turn-on of the input voltage.
The charging current into EMI suppression capacitors is disregarded in the first microseconds after switch-on.

Inrush current max. 13A

peak

at 110Vdc, temperature independent

typ. 4A

peak

at 110Vdc, temperature independent

Inrush energy max. 1A

2

s at 110Vdc, temperature independent

Inrush delay typ. 500ms start-up delay plus rise time at 110Vdc

Fig. 5-1 Typical input inrush current behaviour at nominal load

and 25°C ambient

Aug. 2016 / Rev. 1.0 DS-QS10.241-60-EN
All parameters are specified at 24V, 8.3A, 110Vdc, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.

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5/27

QS10.241-60

Q-Series

24V, 200W, DC/DC CONVERTER

6. OUTPUT

Output voltage nom. 24V
Adjustment range min. 24-28V guaranteed
max. 30V

***)

at clockwise end position of potentiometer
Factory setting typ. 24.1V ±0.2%, at full load, cold unit
Line regulation max. 10mV 77-154Vdc
Load regulation max. 100mV static value, 0A Æ 8.3A
Ripple and noise voltage max. 50mVpp 20Hz to 20MHz, 50Ohm
Output current nom. 8.3A continuously available at 24V, see Fig. 6-1
nom. 7.1A continuously available at 28V, see Fig. 6-1

nom. 12.5A

*)

short term available BonusPower

® *)

,

at 24V, for typical 4s, see Fig. 6-1

nom. 10.7A

*)

short term available BonusPower

® *)

,

at 28V, for typical 4s, see Fig. 6-1
Output power nom. 200W continuously available
nom. 300W

*)

short term available BonusPower

® *)

BonusPower® time typ. 4s duration until the output voltage dips, see Fig. 6-2
min. 3s
max. 5s
BonusPower

®

recovery time typ. 7s overload free time to reset power manager, see Fig. 6-3
Overload behaviour cont. current
Short-circuit current min. 6.7A

**)

continuous, load impedance 100mOhm, see Fig. 6-1

max. 10.5A

**)

continuous, load impedance 100mOhm, see Fig. 6-1

min. 17.5A

**)

during BonusPower

® *)

, load impedance 100mOhm

max. 22.5A

**)

during BonusPower

® *)

, load impedance 100mOhm

max. 12.5A

**)

continuous, load impedance <10mOhm, see Fig. 6-1

Output capacitance typ. 7 000μF included inside the power supply

*) BonusPower®, short term power capability (up to typ. 4s)

The power supply is designed to support loads with a higher short-term power requirement without damage or shutdown. The short­term duration is hardware controlled by an output power manager. This BonusPower® is repeatedly available. Detailed information
can be found in chapter 23.1. If the power supply is loaded longer with the BonusPower

®

than shown in the Bonus-time diagram (see

Fig. 6-2), the max. output power is automatically reduced to 200W.

**) Discharge current of output capacitors is not included.

***) This is the maximum output voltage which can occur at the clockwise end position of the potentiometer due to tolerances. It is not a

guaranteed value, which can be achieved. The typical value is about 28.6V.

Fig. 6-1 Output voltage vs. output current,

typ.

Fig. 6-2 Bonus time vs. output power

c
on

t
i

n

uo

u
s

Output Voltage

0

04 81216

4

8

12

28V

16

20

24

20

A

Output Current

s

h

or

t

-

t

e

r

m

Adjustment

Range

Bonus Time

0

110 120 130 140 150

160%

1

2

3

7

4

5

6

8

9

10s

m

i

n

m

a

x

typ

Output Power

Aug. 2016 / Rev. 1.0 DS-QS10.241-60-EN
All parameters are specified at 24V, 8.3A, 110Vdc, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.

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QS10.241-60

Q-Series

24V, 200W, DC/DC CONVERTER

Fig. 6-3 BonusPower® recovery time

Power
Demand

100%

t

t

Limitation by
Power Manager

Output
Voltage

Bonus Power disabled

Bonus

Time

Recovery Time

The BonusPower

®

is available as soon as power comes on and immediately after the end of an output short circuit or

output overload.

Fig. 6-4 BonusPower® after input turn-on Fig. 6-5 BonusPower® after output short

100%

Output
Voltage

Input
Voltage

Bonus
Power

Output
Power

150%

Short of

Output

100%

Output
Voltage

Bonus
Power

Output
Power

150%

Aug. 2016 / Rev. 1.0 DS-QS10.241-60-EN
All parameters are specified at 24V, 8.3A, 110Vdc, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.

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7/27

QS10.241-60

Q-Series

24V, 200W, DC/DC CONVERTER

7. HOLD-UP TIME

The internal capacitor, which supplies the energy for the hold-up time is isolated by a diode to the input voltage. A
short on the input line does not discharge the internal hold-up capacitor.

Hold-up Time typ. 47ms at 4.15A, see Fig. 7-1
min. 36ms at 4.15A, see Fig. 7-1
typ. 23ms at 8.3A, see Fig. 7-1
min. 18ms at 8.3A, see Fig. 7-1

Fig. 7-1 Hold-up time vs. input voltage Fig. 7-2 Shut-down behavior, definitions

0

10

20

30

40

50ms

70 90 110 130 150Vdc

Input Voltage

Hold-up Time

at 8.3A, typ.

at 4.14A, min.

at 4.15A, typ.

at 8.3A, min.

- 5%

Hold-up Time

Output
Voltage

Input
Voltage

Aug. 2016 / Rev. 1.0 DS-QS10.241-60-EN
All parameters are specified at 24V, 8.3A, 110Vdc, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.

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QS10.241-60

Q-Series

24V, 200W, DC/DC CONVERTER

8. DC-OK RELAY CONTACT

This feature monitors the output voltage, which is produced by the DC/DC converter itself. It is independent of a back­fed voltage from a unit connected in parallel to the DC/DC converter output.

Contact closes As soon as the output voltage reaches the adjusted output voltage level.
Contact opens As soon as the output voltage dips more than 10% below the adjusted output voltage.

Short dips will be extended to a signal length of 250ms. Dips shorter than 1ms will be ignored.

Contact re-closes As soon as the output voltage exceeds 90% of the adjusted voltage.

Contact ratings max 60Vdc 0.3A, 30Vdc 1A, 30Vac 0.5A resistive load
min 1mA at 5Vdc min. permissible load

Isolation voltage See dielectric strength table in section 18.

Fig. 8-1 DC-ok relay contact behavior

250ms

0.9* V

ADJ

<

1ms

10%

open

V

OUT

= V

ADJ

openclosed closed

>

1ms

Note:

The DC-ok feature requires that the output voltage reaches the nominal
(=adjusted) level after turn-on in order to function according to
specification. If this level cannot be achieved, the overload lamp will be
on and the DC-ok contact will be open. The overload signal will only shut
off as soon as the adjusted voltage is reached. This is an important
condition to consider particularly, if the load is a battery, the power
supply is used in parallel or the power supply is used for N+1 redundant
systems.

Aug. 2016 / Rev. 1.0 DS-QS10.241-60-EN
All parameters are specified at 24V, 8.3A, 110Vdc, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.

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QS10.241-60

Q-Series

24V, 200W, DC/DC CONVERTER

9. EFFICIENCY AND POWER LOSSES

Efficiency typ. 93.0% at 110Vdc input and 24V, 8.3A
Average efficiency*) typ. 92.1% 25% at 2.1A, 25% at 4.2A,

25% at 6.2A. 25% at 8.3A
Power losses typ. 4.3W at 110Vdc input and 24V, 0A
typ. 7.8W at 110Vdc input and 24V, 4.2A (= 50% load)
typ. 15.0W at 110Vdc input and 24V, 8.3A

*) The average efficiency is an assumption for a typical application where the DC/DC converter is loaded with 25% of the nominal load for

25% of the time, 50% of the nominal load for another 25% of the time, 75% of the nominal load for another 25% of the time and with
100% of the nominal load for the rest of the time.

Fig. 9-1 Efficiency vs. output current, at 24V,

typ.

Fig. 9-2 Losses vs. output current, at 24V, typ.

Efficiency

123456789A

86

87

88

89

90

91

Output Current

92

93

94%

Power Losses

01234567 9A

0

2

8

10

12

Output Current

14

16W

8

4

6

10. LIFETIME EXPECTANCY AND MTBF

Lifetime expectancy*) 140 000h*) at 24V, 4.2A and 40°C
395 000h*) at 24V, 4.2A and 25°C
266 000h

*)

at 24V, 8.3A and 40°C

428 000h

*)

at 24V, 8.3A and 25°C

MTBF

**)

SN 29500, IEC 61709 688 000h at 24V, 8.3A and 40°C
1 181 000h at 24V, 8.3A and 25°C
MTBF

**)

MIL HDBK 217F 333 000h at 24V, 8.3A and 40°C, Ground Benign GB40
450 000h at 24V, 8.3A and 25°C, Ground Benign GB25
75 000h at 24V, 8.3A and 40°C, Ground Fixed GF40
100 000h at 24V, 8.3A and 25°C, Ground Fixed GF25

*) The Lifetime expectancy shown in the table indicates the minimum operating hours (service life) and is determined by the lifetime

expectancy of the built-in electrolytic capacitors. Lifetime expectancy is specified in operational hours and is calculated according to the
capacitor’s manufacturer specification. The manufacturer of the electrolytic capacitors only guarantees a maximum life of up to 15 years
(131 400h). Any number exceeding this value is a calculated theoretical lifetime which can be used to compare devices.

**) MTBF stands for Mean Time Between Failure, which is calculated according to statistical device failures, and indicates reliability of a

device. It is the statistical representation of the likelihood of a unit to fail and does not necessarily represent the life of a product.

The MTBF figure is a statistical representation of the likelihood of a device to fail. A MTBF figure of e.g. 1 000 000h means that

statistically one unit will fail every 100 hours if 10 000 units are installed in the field. However, it can not be determined if the failed unit
has been running for 50 000h or only for 100h.

Aug. 2016 / Rev. 1.0 DS-QS10.241-60-EN
All parameters are specified at 24V, 8.3A, 110Vdc, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.

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10/27

QS10.241-60

Q-Series

24V, 200W, DC/DC CONVERTER

11. FUNCTIONAL DIAGRAM

Fig. 11-1 Functional diagram

+

+

-

-

DC-ok
contact

Output

Over-

Voltage

Protection

Boost

Converter

(pre

conditioning)

Output

Voltage

Regulator

Output

Filter

DC-ok
Relay

Output
Voltage
Monitor

Output

Power

Manager

Temper-

ature
Shut­down

Overload
LED

DC-ok
LED

Input Fuse
Input Filter
Active Inrush
Limiter

V

OUT

Power

Converter

+

-

Reverse Polarity
and Back-feeding
Protection

Aug. 2016 / Rev. 1.0 DS-QS10.241-60-EN
All parameters are specified at 24V, 8.3A, 110Vdc, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.

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QS10.241-60

Q-Series

24V, 200W, DC/DC CONVERTER

12. TERMINALS AND WIRING

The terminals are IP20 finger safe constructed and suitable for field- and factory wiring. Shipped in open position.

Input and output DC-OK-Signal

Type

Bi-stable, quick-connect spring-clamp
terminals

Bi-stable, quick-connect spring-clamp

terminals
Solid wire max. 6mm2 max. 6mm2
Stranded wire max. 4mm2 max. 4mm2
American Wire Gauge AWG20-10 AWG20-10
Max. wire diameter 2.8mm (including ferrules) 2.8mm (including ferrules)
Wire stripping length 10mm / 0.4inch 10mm / 0.4inch
Screwdriver not required not required
Recommended tightening torque not applicable not applicable

Fig. 12-1 Connecting a wire

Instructions:

a) Use appropriate copper cables that are designed for minimum

operating temperatures of:
60°C for ambient up to 45°C and
75°C for ambient up to 60°C minimum

90°C for ambient up to 70°C minimum.
b) Follow national installation codes and installation regulations!
c) Ensure that all strands of a stranded wire enter the terminal

connection!
d) Do not use the unit without PE connection.
e) Ferrules are allowed.

12/27

1.

Insert the wire

2.

Close the lever

To disconnect wire:
reverse the procedure

Daisy chaining:

Daisy chaining (jumping from one DC/DC converter output to the next) is allowed as long as the average output
current through one terminal pin does not exceed 25A. If the current is higher, use a separate distribution terminal
block as shown in Fig. 12-3.

Fig. 12-2 Daisy chaining of outputs Fig. 12-3 Using distribution terminals

DC/DC

Converter

+ +

- -

Input

Output

Load

+

-

max 25A!

DC/DC

Converter

+ +

- -

Input

Output

Load

+

-

Distribution
Terminals

DC/DC

Converter

+ +

- -

Input

Output

DC/DC

Converter

+ +

- -

Input

Output

Aug. 2016 / Rev. 1.0 DS-QS10.241-60-EN
All parameters are specified at 24V, 8.3A, 110Vdc, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.

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QS10.241-60

Q-Series

24V, 200W, DC/DC CONVERTER

13. FRONT SIDE AND USER ELEMENTS

Fig. 13-1 Front side

A

Input Terminals (Quick-connect spring-clamp terminals)

+ Positive input

– Negative (return) input

PE (Protective Earth) input

B

Output Terminals (Quick-connect spring-clamp terminals, two pins per

pole)
+ Positive output
– Negative (return) output

C

DC-OK Relay Contact (Quick-connect spring-clamp terminals)

The DC-OK relay contact is synchronized with the DC-OK LED.
See chapter 8 for details.

D Output voltage potentiometer

Open the flap to adjust the output voltage. Factory set: 24.1V

E DC-OK LED (green)

On, when the output voltage is >90% of the adjusted output voltage

F

Overload LED (red)

On, when the voltage on the output terminals is <90% of the adjusted
output voltage, or in case of a short circuit in the output. Input voltage is
required
Flashing, when the unit has switched off due to over-temperature.

Indicators, LEDs

Overload LED DC-OK LED DC-OK Contact

Normal mode OFF ON Closed
During BonusPower® OFF ON Closed
Overload (VOUT < 90%) ON OFF Open
Output short circuit ON OFF Open
Temperature Shut-down Intermitted OFF Open
No input power OFF OFF Open

Aug. 2016 / Rev. 1.0 DS-QS10.241-60-EN
All parameters are specified at 24V, 8.3A, 110Vdc, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.

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QS10.241-60

Q-Series

24V, 200W, DC/DC CONVERTER

14. EMC

The DC/DC converter is suitable for rolling stock railway applications, for applications in industrial environment as well
as in residential commercial and light industry environment without any restrictions.

EMC Immunity

According generic standards: EN 61000-6-1 and EN 61000-6-2 and
according to EN 50121-3-2

Electrostatic discharge EN 61000-4-2 contact discharge

air discharge

8kV
15kV

Criterion A

Criterion A
Electromagnetic RF field EN 61000-4-3 80MHz-2.7GHz 20V/m Criterion A
Fast transients (Burst) EN 61000-4-4 input lines

output lines
DC-OK signal (coupling clamp)

4kV
2kV
2kV

Criterion A

Criterion A

Criterion A
Surge voltage on input EN 61000-4-5 + Æ -

+ Æ PE, - Æ PE

2kV
4kV

Criterion A

Criterion A
Surge voltage on output EN 61000-4-5 + Æ -

+ / - Æ PE

0.5kV
1kV

Criterion A

Criterion A
Surge voltage on DC-OK EN 61000-4-5 DC-OK signal Æ PE 1kV Criterion A
Conducted disturbance EN 61000-4-6 0.15-80MHz 10V Criterion A
Power – Frequency magnetic

field

EN 61000-4-8 16.7Hz, 50Hz 100A/m Criterion A

Power – Frequency magnetic
field

EN 61000-4-8 0Hz 300A/m Criterion A

Pulsed magnetic field EN 61000-4-9 300A/m Criterion B

Criterions:
A: DC/DC converter shows normal operation behavior within the defined limits.
B: During the test the output voltage can slightly drift below or above the specified limits.

EMC Emission

According generic standards: EN 61000-6-3 and EN 61000-6-4
and according to EN 50121-3-2

Conducted emission
input lines

CISPR 16-1-2, CISPR 16-2-1 limits for EN 50121-3-2 fulfilled,

limits for DC power port
according EN 61000-6-3 fulfilled

Conducted emission
output lines

CISPR 16-1-2, CISPR 16-2-1 limits for EN 50121-3-2 fulfilled,

limits for DC power port

according EN 61000-6-3 fulfilled
Radiated emission EN 55011, EN 55022, EN 50121-3-2 Class B
This device complies with FCC Part 15 rules.

Operation is subjected to following two conditions: (1) this device may not cause harmful interference, and (2) this
device must accept any interference received, including interference that may cause undesired operation.

Switching Frequencies

The power supply has three converters with three different switching frequencies

included. Two are nearly constant. The other one is input voltage and load dependent.
Switching frequency 1 35kHz nearly constant
Switching frequency 2 105kHz nearly constant
Switching frequency 3 40kHz to 220kHz input voltage and load dependent

Aug. 2016 / Rev. 1.0 DS-QS10.241-60-EN
All parameters are specified at 24V, 8.3A, 110Vdc, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.

www.pulspower.com Phone [phone] Germany

14/27

QS10.241-60

Q-Series

24V, 200W, DC/DC CONVERTER

15. ENVIRONMENT

Conformal coating yes all pc-boards are conformal coated
Operational temperature

*)

-40°C to +70°C (-40°F to 158°F) continuous operation
+70°C to +85°C (185°F to 185°F) for maximal 10 minutes every hour
Storage temperature -40 to +85°C (-40°F to 185°F) for storage and transportation
Humidity

**)

5 to 95% r.h. IEC 60068-2-30

Vibration sinusoidal 2-17.8Hz: ±1.6mm; 17.8-500Hz: 2g

***)

2 hours / axis

IEC 60068-2-6; DC/DC converter in operation

Vibration broadband 1.01grms for 10 minutes; 5-150Hz

***)

IEC 60068-2-64, DC/DC converter in operation;

Tests limits according to EN 61373

Vibration broadband 5.72grms for 300 minutes; 5-150Hz

***)

IEC 60068-2-64, DC/DC converter not in

operation; Tests limits according to EN 61373

Shock 30g 6ms, 20g 11ms, 50g 30ms

***)

3 bumps / direction, 18 bumps in total

IEC 60068-2-27; DC/DC converter in operation

Shock 50g 30ms

***)

3 bumps / direction, 18 bumps in total

IEC 60068-2-27, DC/DC converter not in

operation; Tests limits according to EN 61373
Altitude 0 to 2000m (0 to 6 560ft) without any restrictions
2000 to 6000m (6 560 to 20 000ft) reduce output power or ambient temperature,

see Fig. 15-2

IEC 62103, EN 50178, overvoltage category II
Altitude de-rating 12W/1000m or 5°C/1000m > 2000m (6500ft), see Fig. 15-2
Over-voltage category III IEC 62103, EN 50178, altitudes up to 2000m
II altitudes from 2000m to 6000m
Degree of pollution 2 IEC 62103, EN 50178, not conductive
LABS compatibility The unit does not release any silicone or other LABS-critical substances and is suitable for

use in paint shops.

*) Operational temperature is the same as the ambient temperature and is defined as the air temperature 2cm below the unit.
**) Do not energize while condensation is present
***) Tested in combination with DIN-Rails according to EN 60715 with a height of 15mm and a thickness of 1.3mm and standard

orientation.

Fig. 15-1 Output current vs. ambient temp. at

24V output voltage

Fig. 15-2 Output current vs. altitude at 24V

output voltage

Allowed Output Current

0

-40 0 20 40

85°C

2

4

6

8

12A

60-20 70

10

c

o

n

t

i

n

u

o

u

s

f

o

r

t

y

p

.

4

s

12.5A

f

o

r

m

a

x

.

1

0

m

i

n

u

t

e

s

8.3A

Ambient Temperature

0

0 2000m 4000m

6000m

2

4

6

8

10

12A

8.3A continuous operation

12.5A for typ. 4s

Allowable Output Current

Altitude

B

C

A

.

.

.

T

a

m

b

<

7

0

°

C

B

.

.

.

T

a

m

b

<

6

0

°

C

C

.

.

.

T

a

m

b

<

5

0

°

C

A

Aug. 2016 / Rev. 1.0 DS-QS10.241-60-EN
All parameters are specified at 24V, 8.3A, 110Vdc, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.

www.pulspower.com Phone [phone] Germany

15/27

QS10.241-60

Q-Series

24V, 200W, DC/DC CONVERTER

16. PROTECTION FEATURES

Output protection Electronically protected against overload, no-load and short-circuits

*)

Output over-voltage protection typ. 35Vdc

max. 39Vdc

In case of an internal DC/DC converter defect, a
redundant circuit limits the maximum output voltage.
The output shuts down and automatically attempts to

restart.
Degree of protection IP 20 EN/IEC 60529
Penetration protection > 3.5mm e.g. screws, small parts
Over-temperature protection yes Output shut-down with automatic restart
Input transient protection MOV (Metal Oxide Varistor)
Internal input fuse DC suitable fuse included not user replaceable
Reverse input polarity protection yes unit does not start, no signalling

*) In case of a protection event, audible noise may occur.

17. SAFETY FEATURES

Classification of output voltage SELV IEC/EN 60950-1
PELV IEC/EN 60204-1, EN 50178, IEC 62103, IEC 60364-4-41
double or reinforced isolation to the input voltage
Class of protection I PE (Protective Earth) connection required
Isolation resistance > 5MOhm input to output, 500Vdc
PE resistance < 0.1Ohm
Touch current (leakage current) The leakage current which is produced by the DC/DC converter itself depends on the

input voltage ripple and need to be investigated in the final application.
For a smooth DC input voltage, the produced leakage current is less than 100μA.

Aug. 2016 / Rev. 1.0 DS-QS10.241-60-EN
All parameters are specified at 24V, 8.3A, 110Vdc, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.

www.pulspower.com Phone [phone] Germany

16/27

QS10.241-60

Q-Series

24V, 200W, DC/DC CONVERTER

18. DIELECTRIC STRENGTH

The output voltage is floating and has no ohmic connection to the ground. Type and factory tests are conducted by
the manufacturer. Field tests may be conducted in the field using the appropriate test equipment which applies the
voltage with a slow ramp (2s up and 2s down). Connect all input-terminals together as well as all output poles before
conducting the test. When testing, set the cut-off current settings to the value in the table below.

Fig. 18-1 Dielectric strength

A B C D

Type test 60s 2500Vac 3000Vac 500Vac 500Vac

Factory test 5s 2500Vac 2500Vac 500Vac 500Vac

Field test 5s 2000Vac 2000Vac 500Vac 500Vac

Cut-off current setting > 10mA > 10mA > 20mA > 1mA

AD

C

B

B

*)

-

+

Input DC-ok

Earth, PE

Output

-

+

To fulfil the PELV requirements according to EN60204-1 § 6.4.1, we
recommend that either the + pole, the – pole or any other part of
the output circuit shall be connected to the protective earth
system. This helps to avoid situations in which a load starts
unexpectedly or can not be switched off when unnoticed earth
faults occur.

B*) When testing input to DC-OK ensure that the max. voltage between DC-OK and the output is not exceeded (column D). We recommend

connecting DC-OK pins and the output pins together when performing the test.

Aug. 2016 / Rev. 1.0 DS-QS10.241-60-EN
All parameters are specified at 24V, 8.3A, 110Vdc, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.

www.pulspower.com Phone [phone] Germany

17/27

QS10.241-60

Q-Series

24V, 200W, DC/DC CONVERTER

19. APPROVALS AND DECLARATIONS

EC Declaration of Conformity

The CE mark indicates conformance with the

- EMC directive and the

- Low-voltage directive

Railway applications - Electronic
equipment used on rolling stock.

EN 50155:2007

The manufacturer’s declaration indicate conformance with
the following characteristics:

- Altitude category: AX (EN 50125-1 § 4.2.1)

- Environmental category: TX (EN 50155 § 4.1.2)

- Interruption of voltage supply: S2 (EN 50155 § 5.1.1.2)

- Supply change over: C2 (EN 50155 § 5.1.3)

- Shock and vibration: Category 1, Class A and B (EN 61373)

- EMI: EN 50121-3-2

- Fire Classification: HL3 (EN 45545-2)

20. ROHS, REACH AND OTHER FULFILLED STANDARDS

RoHS Directive

Directive 2011/65/EU of the European Parliament and the
Council of June 8

th

, 2011 on the restriction of the use of
certain hazardous substances in electrical and electronic
equipment.

REACH Directive

Directive 1907/2006/EU of the European Parliament and the
Council of June 1

st

, 2007 regarding the Registration,
Evaluation, Authorisation and Restriction of Chemicals
(REACH)

Aug. 2016 / Rev. 1.0 DS-QS10.241-60-EN
All parameters are specified at 24V, 8.3A, 110Vdc, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.

www.pulspower.com Phone [phone] Germany

18/27

QS10.241-60

Q-Series

24V, 200W, DC/DC CONVERTER

21. PHYSICAL DIMENSIONS AND WEIGHT

Width 60mm 2.36’’
Height 124mm 4.88’’
Depth 117mm 4.61’’

The DIN-rail height must be added to the unit depth to calculate the total required

installation depth.
Weight 920g / 2.03lb
DIN-Rail Use 35mm DIN-rails according to EN 60715 or EN 50022 with a height of 7.5 or 15mm.
Housing material Body: Aluminium alloy

Cover: zinc-plated steel
Installation clearances See chapter 2

Fig. 21-1 Front view Fig. 21-2 Side view

Aug. 2016 / Rev. 1.0 DS-QS10.241-60-EN
All parameters are specified at 24V, 8.3A, 110Vdc, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.

www.pulspower.com Phone [phone] Germany

19/27

QS10.241-60

Q-Series

24V, 200W, DC/DC CONVERTER

22. ACCESSORIES

22.1. ZM13.SIDE - SIDE MOUNTING BRACKET

This bracket is used to mount the DC/DC converter sideways with or without utilizing a DIN-Rail. The two aluminum
brackets and the black plastic slider of the unit have to be detached, so that the steel brackets can be mounted.

For sideway DIN-rail mounting, the removed aluminum brackets and the black plastic slider need to be mounted on
the steel bracket.

Side mounting with DIN-rail brackets Side mounting without DIN-rail brackets

22.2. UF20.241 BUFFER MODULE

This buffer unit is a supplementary device for DC 24V power supplies. It delivers power to bridge typical mains failures

or extends the hold-up time after turn-off
of the input power. In times when the
power supply provides sufficient voltage
the buffer unit stores energy in integrat
electrolytic capacitors. In case of input
voltage fault, this energy is released again
in a regulated process. One buffer module can deliver 20A additional curren

20/27

s,

ed

t.

DC

Buffer

Unit(s)

Power

Supply

Load

AC

+

-

The buffer unit does not require any control wiring. It can be added in parallel to
the load circuit at any given point. Buffer units can be added in parallel to increase
the output ampacity or the hold-up time.

Aug. 2016 / Rev. 1.0 DS-QS10.241-60-EN
All parameters are specified at 24V, 8.3A, 110Vdc, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.

www.pulspower.com Phone [phone] Germany

QS10.241-60

Q-Series

24V, 200W, DC/DC CONVERTER

22.3. YR2.DIODE REDUNDANCY MODULE

21/27

ures.

The YR2.DIODE is a dual redundancy module, which has two diodes

as decoupling devices included. It
can be used for various purposes.
The most popular application is to
configure highly reliable and true
redundant power supply systems.
Another interesting application is
the separation of sensitive loads
from non-sensitive loads. This
avoids the distortion of the power
quality for the sensitive loads
which can cause controller fail

+ -

PE

+ +

- -

QS10.241-60

DC/DC-Conv.

Adj

Overload

DCok

Output

Input

Failure

Monitor

24V

Load

optional

I I

L

N

PE

YR2.Diode

Redundancy
Module

+

-

OUT

+

-

IN 1

+

-

IN 2

+ -

PE

+ +

- -

QS10.241-60

DC/DC-Conv.

Adj

Overload

DCok

Output

Input

Aug. 2016 / Rev. 1.0 DS-QS10.241-60-EN
All parameters are specified at 24V, 8.3A, 110Vdc, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.

www.pulspower.com Phone [phone] Germany

QS10.241-60

Q-Series

24V, 200W, DC/DC CONVERTER

23. APPLICATION NOTES

23.1. REPETITIVE PULSE LOADING

Typically, a load current is not constant and varies over time. This power supply is designed to support loads with a
higher short-term power demand (=BonusPower

®

). The short-term duration is hardware controlled by an output
power manager and is available on a repeated basis. If the BonusPower® load lasts longer than the hardware
controller allows it, the output voltage will dip and the next BonusPower

®

is available after the BonusPower® recovery

time (see chapter 6) has elapsed.
To avoid this, the following rules must be met:

a) The power demand of the pulse must be below 150% of the nominal output power.
b) The duration of the pulse power must be shorter than the allowed BonusPower

®

time. (see output section)

c) The average (R.M.S.) output current must be below the specified continuous output current.

If the R.M.S. current is higher, the unit will respond with a thermal shut-down after a period of time. Use the
maximum duty cycle curve (Fig. 23-2) to check if the average output current is below the nominal current.

Fig. 23-1 Repetitive pulse loads, definitions Fig. 23-2 Max. duty cycle curve

100%

P

PEAKTPEAK

P

0

T

0

max.

150%

150%100

0

0.2

0.4

0.6

0.8

1.0

DutyCycle

110 120 130 140

P

PEAK

P0

=

1

0

%

P

0

=

5

0

%

P

0

=

7

5

%

P

0

=

1

0

0

%

P

0

Base load (W)

P

PEAK

Pulse load (above 100%)

T

0

Duration between pulses (s)

T

PEAK

Pulse duration (s)

D

utyCycle

T0 =

T

peak -

(D

utyCycle

x T

peak

)

T

peak + T0

T

peak

D

utyCycle

=

Example: A load is powered continuously with 100W (= 50% of the rated output load). From time to time a peak

power of 300W (= 150% of the rated output load) is needed for 1 second.

The question is: How often can this pulse be supplied without overloading the power supply?

- Make a vertical line at P

PEAK

= 150% and a horizontal line where the vertical line crosses the P0 = 50%

curve. Read the max. duty cycle from the duty cycle-axis (= 0.37)

- Calculate the required pause (base load) length T

0

:

22/27

- Result: The required pause length = 1.7s

- Max. repetition rate = pulse +pause length = 2.7s

More examples for pulse load compatibility:

P

PEAK

P0 T

PEAK

T0 P

PEAK

P0 T

PEAK

T0
300W 200W 1s >25s 300W 100W 0.1s >0.16s
300W 0W 1s >1.3s 300W 100W 1s >1.6s
250W 100W 1s > 0.75s 300W 100W 3s >4.9s

D

utyCycle

T0=

T

peak -

(D

utyCycle

x T

peak

)

0.37

1s - (0.37 x 1s)

==1.7s

Aug. 2016 / Rev. 1.0 DS-QS10.241-60-EN
All parameters are specified at 24V, 8.3A, 110Vdc, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.

www.pulspower.com Phone [phone] Germany

QS10.241-60

Q-Series

24V, 200W, DC/DC CONVERTER

23.2. PEAK CURRENT CAPABILITY

The DC/DC converter can deliver peak currents (up to several milliseconds) which are higher than the specified short
term currents. This helps to start current demanding loads. Solenoids, contactors and pneumatic modules often have a
steady state coil and a pick-up coil. The inrush current demand of the pick-up coil is several times higher than the
steady-state current and usually exceeds the nominal output current. The same situation applies when starting a
capacitive load.

The peak current capability also ensures the safe operation of subsequent circuit breakers of load circuits. The load
branches are often individually protected with circuit breakers or fuses. In case of a short or an overload in one branch
circuit, the fuse or circuit breaker need a certain amount of over-current to open in a timely manner. This avoids
voltage loss in adjacent circuits.

The extra current (peak current) is supplied by the built-in large sized output capacitors of the DC/DC converter. The
capacitors get discharged during such an event, which causes a voltage dip on the output. The following two examples
show typical voltage dips:

Fig. 23-3 Peak load with 2x the nominal

current for 50ms, typ.

Fig. 23-4 Peak load with 5x the nominal

current for 5ms, typ.

10ms/DIV

Output
Voltage

Output
Current

24V

0A

16.6A

22.5V

1ms/DIV

Output
Voltage

Output
Current

24V

0A

41.5A

14.5V

16.6A Peak load (resistive) for 50ms
Output voltage dips from 24V to 22.5V.

41.5A Peak load (resistive) for 5ms
Output voltage dips from 24V to 14.5V.

Peak current voltage dips typ. from 24V to 22.5V at 16.6A for 50ms, resistive load
typ. from 24V to 19V at 41.5A for 2ms, resistive load
typ. from 24.5V to 14.5V at 41.5A for 5ms, resistive load

23.3. INDUCTIVE AND CAPACITIVE LOADS

The unit is designed to supply any kind of loads, including unlimited capacitive and inductive loads.

Aug. 2016 / Rev. 1.0 DS-QS10.241-60-EN
All parameters are specified at 24V, 8.3A, 110Vdc, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.

www.pulspower.com Phone [phone] Germany

23/27

QS10.241-60

Q-Series

24V, 200W, DC/DC CONVERTER

23.4. EXTERNAL INPUT PROTECTION

The unit is tested and approved for branch circuits up to 20A. An external protection is only required if the supplying
branch has an ampacity greater than this. Check also local codes and local requirements. In some countries local
regulations might apply.

If an external fuse is necessary or utilized, minimum requirements need to be considered to avoid nuisance tripping of
the circuit breaker. A minimum value of 6A B- or 4A C-Characteristic breaker should be used.

23.5. CHARGING OF BATTERIES

The DC/DC converter can be used to charge lead-acid or maintenance free batteries. (Two 12V batteries in series)

Instructions for charging batteries:

a) Set output voltage (measured at no load and at the battery end of the cable) very precisely to the end-of-charge

voltage.

End-of-charge voltage 27.8V 27.5V 27.15V 26.8V

Battery temperature 10°C 20°C 30°C 40°C

b) Use a 15A or 16A circuit breaker (or blocking diode) between the DC/DC converter and the battery.
c) Ensure that the output current of the DC/DC converter is below the allowed charging current of the battery.
d) Use only matched batteries when putting 12V types in series.
e) The return current to the power supply (battery discharge current) is typ. 3mA when the power supply is switched

off (except in case a blocking diode is utilized).

23.6. PARALLEL USE TO INCREASE OUTPUT POWER

QS10.241-60 DC/DC converters can be paralleled to increase the output power. The output voltage shall be adjusted to
the same value (±100mV) with the same load conditions on all units, or the units can be left with the factory settings.
The ambient temperature is not allowed to exceed +60°C.

If more than three units are connected in parallel, a fuse or circuit breaker with a rating of 15A or 16A is required on
each output. Alternatively, a diode or redundancy module can also be utilized.

Fig. 23-5 Parallel use to increase the output power

Instructions for parallel use:

Unit A

Unit B

-

+

-

+

Load

+

-

Input

Output

Input

Output

- Keep an installation clearance of 15mm (left / right)
between two DC/DC converters and avoid installing the
DC/DC converters on top of each other.

- Do not parallel DC/DC converters in orientations other
than the standard mounting orientation (terminals on
bottom of the unit) or in any other condition where a
derating of the output current is required (e.g. altitude,
temperature, input voltages).

- Pay attention that EMI and inrush current will increase
when using multiple DC/DC converters.

Aug. 2016 / Rev. 1.0 DS-QS10.241-60-EN
All parameters are specified at 24V, 8.3A, 110Vdc, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.

www.pulspower.com Phone [phone] Germany

24/27

QS10.241-60

Q-Series

24V, 200W, DC/DC CONVERTER

23.7. PARALLEL USE FOR REDUNDANCY

QS10.241-60 DC/DC converters can be paralleled for redundancy to gain higher system availability. Redundant systems
require a certain amount of extra power to support the load in case one DC/DC converter unit fails. The simplest way is
to put two DC/DC converters in parallel. This is called a 1+1 redundancy. In case one DC/DC converter unit fails, the
other one is automatically able to support the load current without any interruption. Redundant systems for a higher
power demand are usually built in a N+1 method. E.g. five power supplies, each rated for 8.3A are paralleled to build
a 33.2A redundant system.

For N+1 redundancy the same restrictions apply as for increasing the output power, see also section 23.6.

Please note: This simple way to build a redundant system does not cover failures such as an internal short circuit in
the secondary side of the power supply. In such a case, the defective unit becomes a load for the other power supplies
and the output voltage can not be maintained any more. This can be avoided by utilizing decoupling diodes which are
included in the redundancy module YR2.DIODE.

Fig. 23-6 Redundant power design

+ -

PE

+ +

- -

QS10.241-60

DC/DC-Conv.

Adj

Overload

DCok

Output

Input

Failure

Monitor

24V

Load

optional

I I

L
N

PE

YR2.Diode

Redundancy
Module

+

-

OUT

+

-

IN 1

+

-

IN 2

+ -

PE

+ +

- -

QS10.241-60

DC/DC-Conv.

Adj

Overload

DCok

Output

Input

Recommendations for building redundant power
systems:

- Use separate input fuses for each DC/DC converter.

- Monitor the individual DC/DC converter units.
Use the DC-OK relay contact of the QS10 DC/DC
converter.

- It is desirable to set the output voltages of all units
to the same value (± 100mV) or leave it at the
factory setting.

23.8. SERIES OPERATION

DC/DC converters of the same type can be connected in series for higher output voltages. It is possible to connect as
many units in series as needed, providing the sum of the output voltage does not exceed 150Vdc. Voltages with a
potential above 60Vdc are not SELV any more and can be dangerous. Such voltages must be installed with a protection
against touching.

Avoid return voltage (e.g. from a decelerating motor or battery) which is applied to the output terminals.

Fig. 23-7 Parallel use to increase the output power

Instructions for series use:

Unit A

Input

Output

Unit B

-

+

-

+

Load

+

-

Input

Output

- Keep an installation clearance of 15mm (left / right)
between two DC/DC converters and avoid installing the
DC/DC converters on top of each other.

- Do not use DC/DC converters in series in mounting
orientations other than the standard mounting orientation
(terminals on bottom of the unit).

- Pay attention that EMI and inrush current will increase
when using multiple DC/DC converters.

Aug. 2016 / Rev. 1.0 DS-QS10.241-60-EN
All parameters are specified at 24V, 8.3A, 110Vdc, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.

www.pulspower.com Phone [phone] Germany

25/27

QS10.241-60

Q-Series

24V, 200W, DC/DC CONVERTER

23.9. BACK-FEEDING LOADS

Loads such as decelerating motors and inductors can feed voltage back to the DC/DC converter. This feature is also
called return voltage immunity or resistance against Back- E.M.F. (E

lectro Magnetic Force).

This DC/DC converter is resistant and does not show malfunctioning when a load feeds back voltage to the DC/DC
converter. It does not matter whether the DC/DC converter is on or off.

The maximum allowed feed-back-voltage is 35Vdc.

23.10. USE IN A TIGHTLY SEALED ENCLOSURE

When the DC/DC converter is installed in a tightly sealed enclosure, the temperature inside the enclosure will be
higher than outside. In such situations, the inside temperature defines the ambient temperature for the DC/DC
converter.

The following measurement results can be used as a reference to estimate the temperature rise inside the enclosure.
The DC/DC converter is placed in the middle of the box, no other heat producing items are inside the box
Enclosure: Rittal Typ IP66 Box PK 9519 100, plastic, 180x180x165mm

Load: 24V, 6.6A; (=80%) load is placed outside the box
Input: 110Vdc
Temperature inside enclosure: 38.9°C (in the middle of the right side of the DC/DC converter with a distance of 2cm)
Temperature outside enclosure: 22.1°C
Temperature rise: 16.8K

Aug. 2016 / Rev. 1.0 DS-QS10.241-60-EN
All parameters are specified at 24V, 8.3A, 110Vdc, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.

www.pulspower.com Phone [phone] Germany

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QS10.241-60

Q-Series

24V, 200W, DC/DC CONVERTER

Aug. 2016 / Rev. 1.0 DS-QS10.241-60-EN
All parameters are specified at 24V, 8.3A, 110Vdc, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.

www.pulspower.com Phone [phone] Germany

23.11. MOUNTING ORIENTATIONS

Mounting orientations other than all terminals on the bottom require a reduction in continuous output power or a
limitation in the maximum allowed ambient temperature. The amount of reduction influences the lifetime expectancy
of the DC/DC converter. Therefore, two different derating curves for continuous operation can be found below:

Curve A1 Recommended output current.
Curve A2 Max allowed output current (results in approximately half the lifetime expectancy of A1).

Fig. 23-8
Mounting
Orientation A

(Standard
orientation)

Power
Supply

OUTPUT

INPUT

Output Current

0

20 30 40 50

70°C

2

4

6

8A

60

A

1

Ambient Temperature

8.3A

Fig. 23-9

Mounting
Orientation B

(Upside down)

Power

Supply

OUTPUT

INPUT

Output Current

0

20 30 40 50

70°C

2

4

6

8A

60

A

2

Ambient Temperature

A

1

8.3A

Fig. 23-10

Mounting
Orientation C

(Table-top
mounting)

Output Current

0

20 30 40 50

70°C

2

4

6

8A

60

Ambient Temperature

A

1

A

2

8.3A

Fig. 23-11

Mounting
Orientation D

(Horizontal cw)

Power

Supply

OUTPUT

INPUT

Output Current

0

20 30 40 50

70°C

2

4

6

8A

60

Ambient Temperature

A

1

A

2

8.3A

Fig. 23-12

Mounting
Orientation E

(Horizontal ccw)

Power

Supply

OUTPUT

INPUT

Output Current

0

20 30 40 50

70°C

2

4

6

8A

60

Ambient Temperature

A

1

A

2

8.3A

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