QS3.241
24V, 3.4A, SINGLE PHASE INPUT

Q-Series

POWER SUPPLY
▪
▪
▪
▪
▪
▪
▪
▪
▪
▪

AC 100-240V Wide-range Input
Width only 32mm
Efficiency up to 90%
150% (120W) Peak Load Capability
Easy Fuse Tripping due to High Overload Current
Negligible low Inrush Current Surge
Short-term Operation down to 60Vac and up to 300Vac
Full Power Between -25°C and +60°C
Quick-connect Spring-clamp Terminals
3 Year Warranty

PRODUCT DESCRIPTIONSHORT-FORM DATA

The most outstanding features of this Dimension Q-Series DIN rail
power supply are the high efficiency and the small size, which areachieved by a synchronous rectification and further novel design
details. The Q-Series is part of the Dimension family, existingalongside the lower featured C-Series.

Output voltage
Adjustment range
Output current

With short-term peak power capability of 150% and built-in large
sized output capacitors, these features help start motors, charge
capacitors and absorb reverse energy and often allow a unit of alower wattage class to be used.

Output power

High immunity to transients and power surges as well as low
electromagnetic emission makes usage in nearly every environment
possible.
The integrated output power manager, a wide range input voltage
design and virtually no input inrush current make installation andusage simple. Diagnostics are easy due to a green DC-OK LED and
red overload LED.
Unique quick-connect spring-clamp terminals allow a safe and fast
installation and a large international approval package for a variety
of applications makes this unit suitable for nearly every situation.

ORDER NUMBERS
Power Supply

QS3.241

Accessory

ZM1.WALL
ZM11.SIDE

Output ripple
Input voltage
Mains frequency
AC Input current
Power factor
AC Inrush current
Efficiency
LossesTemperature range
Derating
Hold-up time
Dimensions

DC 24V24 - 28V
3.4 – 3.0A
5 – 4.5A
80W
120W< 50mVpp
AC 100-240V
50-60Hz1.42 / 0.82A
0.53 / 0.47
typ. 5 / 10A peak
88.7 / 90.0%
10.4 / 9.1W
-25°C to +70°C
2W/°C
typ. 41 / 174ms
32x124x102mm

continuous
for typ. 4s
continuous
for typ. 4s
20Hz to 20MHz±15%±6%
at 120 / 230Vac
at 120 / 230Vac
at 120 / 230Vac
at 120 / 230Vac
at 120 / 230Vac
operational+60 to +70°C
at 120 / 230Vac
WxHxD

MAIN APPROVALS
For details and the complete approval list, see chapter 18.

Wall mount bracket
Side mount bracket

UL508

UL 60950-1

MarineMarineNov. 2023 / Rev. 2.5 DS-QS3.241-EN
All parameters are specified at 24V, 3.4A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0 Germany

Class I Div 2

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24V, 3.4A, SINGLE PHASE INPUT

Q-Series

INDEX
Page
1.
2.

Intended Use ................................................................ 3
Installation Instructions ................................................ 3
2.1.
Hazardous Location Areas ................................ 4
3. AC-Input ....................................................................... 5
4. DC-Input ....................................................................... 6
5. Input Inrush Current ..................................................... 6
6. Output .......................................................................... 7
7. Hold-up Time ................................................................ 9
8. Efficiency and Power Losses ....................................... 10
9. Lifetime Expectancy and MTBF .................................. 11
10. Functional Diagram .................................................... 12
11. Terminals and Wiring ................................................. 12
12. Front Side and User Elements .................................... 13
13. EMC ............................................................................ 14
14. Environment ............................................................... 15
15. Protection Features .................................................... 16
16. Safety Features........................................................... 16
17. Dielectric Strength ...................................................... 16
18. Approved, Fulfilled or Tested Standards .................... 17
19. Regulatory Product Compliance ................................. 18
20. Physical Dimensions and Weight ................................ 19Page
21. Accessories................................................................. 20
21.1. ZM1.WALL - Wall Mounting Bracket ................ 20
21.2. ZM11.SIDE - Side Mounting Bracket................. 20
21.3. UF20.241 Buffer Module .................................. 2121.4. YRM2.DIODE Redundancy Module .................. 21
22. Application Notes....................................................... 2222.1. Repetitive Pulse Loading .................................. 2222.2. Peak Current Capability .................................... 23
22.3. Back-feeding Loads .......................................... 23
22.4. External Input Protection ................................. 23
22.5. Charging of Batteries ........................................ 24
22.6. Parallel Use to Increase Output Power ............ 24
22.7. Parallel Use for Redundancy ............................ 24
22.8. Daisy Chaining of Outputs ................................ 25
22.9. Series Operation............................................... 25
22.10. Inductive and Capacitive Loads ........................ 25
22.11. Operation on Two Phases ................................ 26
22.12. Use in a Tightly Sealed Enclosure ..................... 26
22.13. Mounting Orientations ..................................... 27

The information given in this document is correct to the best of our knowledge and experience at the time of publication. If not
expressly agreed otherwise, this information does not represent a warranty in the legal sense of the word. As the state of ourknowledge and experience is constantly changing, the information in this data sheet is subject to revision. We therefore kindly ask you
to always use the latest issue of this document (available under www.pulspower.com).
No part of this document may be reproduced or utilized in any form without our prior permission in writing.

TERMINOLOGY AND ABREVIATIONSPE andsymbolPE 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.

AC 230V

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)

230VacA figure with the unit (Vac) at the end is a momentary figure without any additional tolerances included.

50Hz vs. 60Hz

As long as not otherwise stated, AC 230V parameters are valid at 50Hz mains frequency.

may

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

shall

A key word indicating a mandatory requirement.

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

Nov. 2023 / Rev. 2.5 DS-QS3.241-EN
All parameters are specified at 24V, 3.4A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0 Germany

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QS3.241
24V, 3.4A, SINGLE PHASE INPUT

Q-Series

1. INTENDED USEThis device is designed for installation in an enclosure and is intended for commercial use, such as in industrial control, process control,
monitoring and measurement equipment or the like.
Do not use this device in equipment, where malfunctioning may cause severe personal injury or threaten human life without additional
appropriate safety devices, that are suited for the end-application.
If this device is used in a manner outside of its specification, the protection provided by the device may be impaired.

2. INSTALLATION INSTRUCTIONSWARNING

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

- Turn power off before working on the device. Protect against inadvertent re-powering.
- Do not open, modify or repair the device.
- 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.

Obey the following installation instructions: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
Install device in an enclosure providing protection against electrical, mechanical and fire hazards. Install the device onto a DIN rail
according to EN 60715 with the input terminals on the bottom of the device. Other mounting orientations require a reduction in output
current.
Make sure that the wiring is correct by following all local and national codes. Use appropriate copper cables that are designed for aminimum operating temperature of 60°C for ambient temperatures up to +45°C, 75°C for ambient temperatures up to +60°C and 90°C
for ambient temperatures up to +70°C. Ensure that all strands of a stranded wire enter the terminal connection. Use ferrules for wires
on the input terminals.
The device is designed for pollution degree 2 areas in controlled environments. No condensation or frost is allowed.
The enclosure of the device provides a degree of protection of IP20. The housing does not provide protection against spilled liquids.
The device is designed for overvoltage category II zones. Below 2000m altitude the device is tested for impulse withstand voltages up to
4kV, which corresponds to OVC III according to IEC 60664-1.
The device is designed as “Class of Protection I” equipment according to IEC 61140. Do not use without a proper PE (Protective Earth)connection.
The device is suitable to be supplied from TN, TT or IT mains networks. The continuous voltage between the input terminal and the PE
potential must not exceed 276Vac.
The input can also be powered from batteries or similar DC sources. The continuous voltage between the supply voltage and thePE/ground potential must not exceed 150Vdc.
A disconnecting means shall be provided for the input of the device.
The device is designed for convection cooling and does not require an external fan. Do not obstruct airflow and do not cover ventilation
grid!
The device is designed for altitudes up to 5000m. Above 2000m a reduction in output current is required. Keep the following minimum
installation clearances: 40mm on top, 20mm on the bottom, 5mm left and right side. Increase the 5mm to 15mm in case the adjacentdevice is a heat source. When the device is permanently loaded with less than 50%, the 5mm can be reduced to zero.

Nov. 2023 / Rev. 2.5 DS-QS3.241-EN
All parameters are specified at 24V, 3.4A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0 Germany

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QS3.241
24V, 3.4A, SINGLE PHASE INPUT

Q-Series

The device is designed, tested and approved for branch circuits up to 20A without additional protection device. If an external fuse isutilized, do not use circuit breakers smaller than 6A B- or 4A C-Characteristic to avoid a nuisance tripping of the circuit breaker.
The maximum surrounding air temperature is +70°C. The operational temperature is the same as the ambient or surrounding air
temperature and is defined 2cm below the device. The device is designed to operate in areas between 5% and 95% relative humidity.

2.1. HAZARDOUS LOCATION AREAS
Do not use with DC input voltages or above +60°C ambient temperature.
The device is suitable for use in Class I Division 2 Groups A, B, C, D locations.
WARNING EXPLOSION HAZARDS!
Substitution of components may impair suitability for this environment.
Do not disconnect the device or operate the voltage adjustment unless power has been switched off or the area is known to be nonhazardous.

Nov. 2023 / Rev. 2.5 DS-QS3.241-EN
All parameters are specified at 24V, 3.4A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0 Germany

4/27

QS3.241
24V, 3.4A, SINGLE PHASE INPUT

Q-Series

3. AC-INPUT
AC inputnom.

Allowed voltage L or N to earth
Input frequency
Turn-on voltage
Shut-down voltage

Input current
Power factor *)Crest factor **)Start-up delay
Rise timeTurn-on overshoot

max.
nom.
typ.
typ.

AC 100-240V
85-276Vac
60-85Vac
276-300Vac
276Vac50–60Hz
61Vac
58Vac

typ.
typ.
typ.
typ.
typ.
typ.
max.

AC 100V
1.67A
0.55
3.33
360ms
6ms
20ms
100mV

suitable for TN-, TT- and IT mains networks
full power for 200ms, no damage between 0 and 85Vac< 500ms
continuous, IEC 61010-2-201±6%
steady-state value, see Fig. 3-1
steady-state value, see Fig. 3-1
AC 120V
1.42A
0.53
3.9
350ms
5ms
20ms
100mV

AC 230V
0.82A
0.47
3.88
330ms
7ms
22ms
100mV

at 24V, 3.4A, see Fig. 3-3
at 24V, 3.4A, see Fig. 3-4
at 24V, 3.4A
see Fig. 3-2
0mF, 24V, 3.4A, see Fig. 3-2
3.4mF, 24V, 3.4A, see Fig. 3-2
see Fig. 3-2*) The power factor is the ratio of the true (or real) power to the apparent power in an AC circuit.
**) The crest factor is the mathematical ratio of the peak value to RMS value of the input current waveform.

Fig. 3-1 Input voltage range

Turn-onShut -dow n

full
power
for
200ms

max.
500ms

Input
Voltage- 5%

OutputVoltage

VIN
60V

85V

Start-up
delay

Input
Current, typ.

Fig. 3-4 Power factor vs. output load

0.6
c
Va

0
10
Vac
120

1.5
1.2

ac
230V

0.9
0.6

Power
Factor, typ.

0.5

Vac
100
ac
120V

0.45

230Vac

0.55

0.4

0.3
0
0.5

Rise
Time

276V 300Vac

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

1.8A

Overshoot

Rated
input range

POUT

Fig. 3-2 Turn-on behavior, definitions

Output Current

1.0

1.5

2.0

2.5

3.0 3.5A

0.35
0.5

Output Current

1.0

1.5

2.0

Nov. 2023 / Rev. 2.5 DS-QS3.241-EN
All parameters are specified at 24V, 3.4A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0 Germany

2.5

3.0 3.5A

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24V, 3.4A, SINGLE PHASE INPUT

Q-Series

4. DC-INPUT
DC input
DC input range
DC input current
Allowed Voltage L/N to Earth
Turn-on voltage
Shut-down voltagenom.

DC 110-125V
88-150Vdc
0.8A
150Vdc
61Vdc
47Vdc

typ.
max.
typ.
typ.

+

Power Supply
AC
L
N
PE

-

110Vdc, at 24V, 3.4A
IEC 61010-2-201
steady state value
steady state value

Instructions for DC use:a) Use a battery or similar DC source.
For other sources contact PULSb) Connect +pole to L and –pole to N.
c) Connect the PE terminal to a earth wire or to the machine ground.

Fig. 4-1 Wiring for DC Input

Battery-20%/+20%

+
Load

DC

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

Inrush current
Inrush energy

AC 100V
6Apeak
4.5Apeak
2A2s

max.
typ.
max.

AC 120V
7Apeak5Apeak2A2s

AC 230V
13Apeak
10Apeak
2A2sover entire temperature range
over entire temperature range
over entire temperature range

Fig. 5-1 Input inrush current, typical behavior

Input Current

Input Voltage

Input:
Output:Ambient:
Upper curve:
Middle curve:
Lower curve:Time basis:

230Vac
24V, 3.4A
25°C
Input current 5A / DIVInput voltage 500V / DIV
Output voltage 20V / DIV
100ms / DIV

Output Voltage

Nov. 2023 / Rev. 2.5 DS-QS3.241-EN
All parameters are specified at 24V, 3.4A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0 Germany

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QS3.241
24V, 3.4A, SINGLE PHASE INPUT

Q-Series

6. OUTPUT
Output voltage
Adjustment range
Factory settingLine regulation
Load regulation
Ripple and noise voltage
Output current

Output power
BonusPower time

BonusPower recovery time
Overload behaviour
Short-circuit current

Output capacitance
*)

**)
***)

nom.
max.
typ.
max.
max.
max.
nom.
nom.
nom.

24V
24-28V
30V ***)
24.1V
10mV
100mV
50mVpp
3.4A
3A
5A *)

nom.

4.5A *)

nom.
nom.
typ.
min.
max.
typ.

80W / 84W
120W / 126W *)
4s
3s
5s
7s
cont. current
3.5A **)
4.2A **)
5.2A **)
6.0A **)
6.0A **)
1 500µF

min.
max.
min.
max.
max.
typ.

guaranteed
at clockwise end position of potentiometer±0.2%, at full load, cold unit
60-300Vac
static value, 0A → 3.4A
20Hz to 20MHz, 50Ohm
continuously available at 24V, see Fig. 6-1
continuously available at 28V, see Fig. 6-1
short term available BonusPower *),at 24V, for typical 4s, see Fig. 6-1
short term available BonusPower *),at 28V, for typical 4s, see Fig. 6-1
continuously available at 24V / 28V
short term available BonusPower *) at 24V / 28V
duration until the output voltage dips, see Fig. 6-2

overload free time to reset power manager, see Fig. 6-3
continuous, load impedance 25mOhm, see Fig. 6-1
continuous, load impedance 25mOhm, see Fig. 6-1
during BonusPower *), load impedance 25mOhm
during BonusPower *), load impedance 25mOhm
continuous, load impedance <10mOhm, see Fig. 6-1
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 short-term duration is
hardware controlled by an output power manager. This BonusPower is repeatedly available. Detailed information can be found in chapter 22.1. If thepower 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 80/84W.
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 guaranteed value
which can be achieved. The typical value is about 28.6V.

Peak current capability (up to several milliseconds)
The power supply can deliver a peak current which is higher than the specified short term current. This helps to start current demanding
loads or to safely operate subsequent circuit breakers.
The extra current is supplied by the output capacitors inside the power supply. During this event, the capacitors will be discharged andcauses a voltage dip on the output. Detailed curves can be found in chapter 22.2.
Peak current voltage dips

typ.
typ.
typ.

from 24V to 18.5V
from 24V to 12V
from 24V to 7.5V

at 6.8A for 50ms, resistive load
at 13.5A for 2ms, resistive load
at 13.5A for 5ms, resistive load

Nov. 2023 / Rev. 2.5 DS-QS3.241-EN
All parameters are specified at 24V, 3.4A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0 Germany

7/27

QS3.241
24V, 3.4A, SINGLE PHASE INPUT

Q-Series

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

Fig. 6-2 Bonus time vs. output power

Adjustment
Range

Output Voltage

28V

Bonus Time

10s
9
8
7
6
5
4
3
2
1
0
110

24
sh o rt -t er m

con tin uou s

20
16
12
8
4
0

Output Current

0

1

2

3

4

5

6A

m ax

typ

m in
Output Power

120

130

140

150

160%

Fig. 6-3 BonusPower recovery time
Limitation by
Power Manager

Power
Demand
100%

t
Bonus
Time

OutputVoltage

Recovery Time
Bonus Power disabledt

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

Short ofOutput

Input
Voltage

OutputVoltage
OutputVoltage150%
Output
Power

100%

Bonus
Power

Output
Power

150%

Bonus
Power

100%

Nov. 2023 / Rev. 2.5 DS-QS3.241-EN
All parameters are specified at 24V, 3.4A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0 Germany

8/27

QS3.241
24V, 3.4A, SINGLE PHASE INPUT

Q-Series

7. HOLD-UP TIME
Hold-up TimeAC 100V
58ms
28ms

typ.
typ.

Fig. 7-1 Hold-up time vs. input voltage

AC 120V
88ms
41ms

AC 230V
347ms
174ms

at 24V, 1.7A, see Fig. 7-1
at 24V, 3.4A, see Fig. 7-1

Fig. 7-2 Shut-down behavior, definitions

190ms Hold-up Time
170
24V, 1.7A, min.
150 24V, 1.7A, typ.
130
110
90
24V, 3.4A, min.
70
24V, 3.4A, typ.
50
30
Input Voltage
10
85
120
155
190 230Vac

Zero Transition
Input
Voltage- 5%

OutputVoltage
Hold-up Time

Nov. 2023 / Rev. 2.5 DS-QS3.241-EN
All parameters are specified at 24V, 3.4A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0 Germany

9/27

QS3.241
24V, 3.4A, SINGLE PHASE INPUT

Q-Series

8. EFFICIENCY AND POWER LOSSES
Efficiency
Average efficiency *)

typ.
typ.

AC 100V
87.1%
88.9%

AC 120V
88.7%
89.9%

AC 230V
90.0%
88.3%

Power losses

typ.
typ.

0.9W
12.1W

1.0W
10.4W

2.1W
9.1W

*)

at 24V, 3.4A
25% at 0.85A, 25% at 1.7A,
25% at 2.55A. 25% at 3.4A
at 24V, 0A
at 24V, 3.4A

The average efficiency is an assumption for a typical application where the power supply 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 thetime.

Fig. 8-1

Efficiency vs. output current at 24V, typFig. 8-2

Losses vs. output current at 24V, typ.

Efficiency

Power Losses

92%

12W

120
Vac

91
90

230Vac

89

10
0V
ac

88
87

8
230Vac

6
4
2

86
0.5

Fig. 8-3

100Vac120Vac10Output Current

Output Current0

3.0 3.5A

0

Efficiency vs. input voltage at 24V, 3.4A, typ.

Fig. 8-4

1.0

1.5

2.0

2.5

0.5

1.5

2.0

2.5

3.0 3.5A

Losses vs. input voltage at 24V, 3.4A, typ.

Efficiency

Power Losses

92%

18W

91

15

90

12

89

9

88

6

87

1.0

3
Input Voltage

Input Voltage

86
85

120

155

190

0
225 260Vac

85

120

155

Nov. 2023 / Rev. 2.5 DS-QS3.241-EN
All parameters are specified at 24V, 3.4A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0 Germany190

225 260Vac

10/27

QS3.241
24V, 3.4A, SINGLE PHASE INPUT

Q-Series

9. LIFETIME EXPECTANCY AND MTBF
Lifetime expectancy *)MTBF **) SN 29500, IEC 61709
MTBF **) MIL HDBK 217F

AC 100V
48 000h
117 000h
137 000h*)
1 191 000h
2 061 000h
581 000h

AC 120V
62 000h
126 000h
177 000h*)
1 265 000h
2 155 000h
631 000h

AC 230V
79 000h
114 000h
224 000h*)
1 451 000h
2 436 000h
643 000h

812 000h

889 000h

912 000h

at 24V, 3.4A and 40°C
at 24V, 1.7A and 40°C
at 24V, 3.4A and 25°C
at 24V, 3.4A and 40°C
at 24V, 3.4A and 25°C
at 24V, 3.4A and 40°C; Ground
Benign GB40
at 24V, 3.4A and 25°C; Ground
Benign GB25*)

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 statisticalrepresentation 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 failevery 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.

Nov. 2023 / Rev. 2.5 DS-QS3.241-EN
All parameters are specified at 24V, 3.4A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0 Germany

11/27

QS3.241
24V, 3.4A, SINGLE PHASE INPUT

Q-Series

10. FUNCTIONAL DIAGRAM
Fig. 10-1 Functional diagram
OutputVoltage
Regulator

L
N

Input Fuse
Input Filter
Input Rectifier
Inrush LimiterTransient Filter

Temperature
Shutdown

OutputPower
ManagerPower
Converter

OutputOverVoltage
Protection

VOUT

+
+
-

OutputFilterOverload

OutputVoltage
MonitorDCok

11. TERMINALS AND WIRING
Bi-stable, quick-connect spring clamp terminals. IP20 Finger safe construction. Suitable for field- and factory installation. Shipped inopen position.
Type
Solid wire
Stranded wire
American Wire Gauge
Wire stripping length
Screwdriver
Recommended tightening torquePull-out force

Input
Outputspring-clamp terminals
spring-clamp terminals
0.5-6mm2
0.3-4mm2
0.5-4mm2
0.3-2.5mm2
20-10 AWG
26-12 AWG
10mm
6mm
not applicable
not applicable
not applicable
not applicable
10AWG:80N, 12AWG:60N, 14AWG:50N, 16AWG:40N (according to UL486E)

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) Up to two stranded wires with the same cross chapter are permitted in
one connection point (except PE wire).
e) Do not use the unit without PE connection.
f) Unused terminal compartments should be securely tightened.
g) Ferrules are allowed.

Fig. 11-1

Connecting a wire

1. Insert the wire

To disconnect wire:
reverse the procedure

Nov. 2023 / Rev. 2.5 DS-QS3.241-EN
All parameters are specified at 24V, 3.4A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0 Germany

2. Close the lever

12/27

QS3.241
24V, 3.4A, SINGLE PHASE INPUT

Q-Series

12. FRONT SIDE AND USER ELEMENTS
Fig. 12-1 Front sideA

Input Terminals (Quick-connect spring-clamp terminals)
N, LLine input
PE (Protective Earth) input

B

Output Terminals (Quick-connect spring-clamp terminals, two pins per pole)+
Positive output–
Negative (return) output

C

Output voltage potentiometer
Multi turn potentiometer;
Open the flap to adjust the output voltage. Factory set: 24.1V

D

DC-OK LED (green)
On, when the output voltage is >90% of the adjusted output voltage

E

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

Indicators, LEDs
Normal mode
During BonusPower
Overload (VOUT < 90%)
Output short circuit
Temperature Shut-down
No input power

Overload LED
OFF
OFF
ON
ON
Intermitted
OFF

DC-OK LED
ON
ON
OFF
OFF
Intermitted
OFF

Nov. 2023 / Rev. 2.5 DS-QS3.241-EN
All parameters are specified at 24V, 3.4A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0 Germany

13/27

QS3.241
24V, 3.4A, SINGLE PHASE INPUT

Q-Series

13. EMCThe power supply is suitable for applications in industrial environment as well as in residential, commercial and light industry
environment. A detailed EMC report is available on request.
Without additional measures to reduce the conducted emissions on the output (e.g. by using a filter), the device is not suited to supply a
local DC power network in residential, commercial and light industry environments. No restrictions apply for local DC power networks inindustrial environments.
EMC Immunity
Electrostatic discharge
Electromagnetic RF field
Fast transients (Burst)
Surge voltage on input

According generic standards: EN 61000-6-1 and EN 61000-6-2
EN 61000-4-2
contact discharge
air discharge
EN 61000-4-3
80MHz-6GHz
EN 61000-4-4
input lines
output lines
EN 61000-4-5
L→N
L → PE, N → PE

Surge voltage on output

EN 61000-4-5

Conducted disturbance
Mains voltage dips

EN 61000-4-6
EN 61000-4-11

Voltage interruptions
Voltage sags

EN 61000-4-11
SEMI F47

Powerful transients

VDE 0160

8kV
15kV
10V/m
4kV
2kV
2kV
4kV

+→1kV
+ / - → PE
1kV
0.15-80MHz
10V
0% of 100Vac
0Vac, 20ms
40% of 100Vac
40Vac, 200ms
70% of 100Vac
70Vac, 500ms
0% of 200Vac
0Vac, 20ms
40% of 200Vac
80Vac, 200ms
70% of 200Vac
140Vac, 500ms
0% of 200Vac (=0V)
5000msdips on the input voltage according to SEMI F47 standard
80% of 120Vac (96Vac)
1000ms70% of 120Vac (84Vac)
500ms
50% of 120Vac (60Vac)
200ms
over entire load range
750V, 1.3ms

Criterion A
Criterion A
Criterion A
Criterion A
Criterion A
Criterion A
Criterion A
Criterion A
Criterion A
Criterion A
Criterion A
Criterion C
Criterion A
Criterion A
Criterion A
Criterion A
Criterion C
Criterion A
Criterion A
Criterion A
Criterion A

Criterions:
A: Power supply shows normal operation behavior within the defined limits.
C: Temporary loss of function is possible. Power supply may shut-down and restarts by itself. No damage or hazards for the power supply will occur.

EMC Emission
According generic standards: EN 61000-6-3 and EN 61000-6-4
Conducted emission
EN 55011, EN 55032, FCC Part 15, CISPR 11, CISPR 32
Class B
input lines
Conducted emission
IEC/CISPR 16-1-2, IEC/CISPR 16-2-1
limits for DC power port acc. EN
output lines **)61000-6-3 not fulfilled
Radiated emission
EN 55011, EN 55032
Class B
Harmonic input current
EN 61000-3-2
fulfilled for class A equipment
Voltage fluctuations, flicker
EN 61000-3-3
fulfilled *)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.
*) tested with constant current loads, non pulsing**) for information only, not mandatory for EN 61000-6-3

Switching Frequency

65kHz to 270kHz

input voltage and load dependent

Nov. 2023 / Rev. 2.5 DS-QS3.241-EN
All parameters are specified at 24V, 3.4A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0 Germany

14/27

QS3.241
24V, 3.4A, SINGLE PHASE INPUT

Q-Series

14. ENVIRONMENT
Operational temperature *)Storage temperature
Output derating
Humidity **)Vibration sinusoidal-25°C to +70°C-40 to +85°C
2W/°C
5 to 95% r.H.
2-17.8Hz: ±1.6mm; 17.8-500Hz: 2g
2 hours / axis
30g 6ms, 20g 11ms
3 bumps / direction, 18 bumps in total
0 to 2000m
2000 to 5000m

Shock
Altitude

Altitude derating
Over-voltage category

reduce output power according Fig. 14-1
for storage and transportation
60-70°C
IEC 60068-2-30
IEC 60068-2-6
IEC 60068-2-27
without any restrictions
reduce output power or ambient temperature,
see Fig. 14-2
IEC 61010-2-201, overvoltage category II> 2000m, see Fig. 14-2
IEC 61010-2-201, altitudes up to 2000m
altitudes from 2000m to 5000m
IEC 61010-2-201, not conductive

5W/1000m or 5°C/1000m
III
II
2

Degree of pollution*) 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

Fig. 14-1 Output current vs. ambient temp.

Fig. 14-2 Output current vs. altitude
Al lowed Output
Wattage at 24V

Allowed Output
Wattage at 24V

120W

120W

f or t yp. 4s

100

100
80

80

continuous

60

60

40

40

20

20
Ambient Temperature

0
-25

0

20

40

Al titude

0
60 70°C

02000

Nov. 2023 / Rev. 2.5 DS-QS3.241-EN
All parameters are specified at 24V, 3.4A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0 Germany

4000

5000m

15/27

QS3.241
24V, 3.4A, SINGLE PHASE INPUT

Q-Series

15. PROTECTION FEATURES
Output protection
Output over-voltage protection

Electronically protected against overload, no-load and short-circuits *)typ. 34Vdc
In case of an internal power supply defect, a redundant circuit
limits the maximum output voltage. The output shuts down andmax. 36Vdc
automatically attempts to restart.
IP 20
EN/IEC 60529> 3.5mme.g. screws, small partsyes
Output shut-down with automatic restart
MOV (Metal Oxide Varistor)
T6A3 H.B.C.
not user replaceable

Degree of protection
Penetration protection
Over-temperature protection
Input transient protection
Internal input fuse*)

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

16. SAFETY FEATURES
Input / output separation *)

SELV
PELV
I
> 100MOhm< 0.1Ohm
typ. 0.11mA / 0.26mA
typ. 0.15mA / 0.38mA
typ. 0.25mA / 0.63mA< 0.14mA / 0.31mA< 0.20mA / 0.46mA< 0.35mA / 0.8mAClass of protection
Isolation resistancePE resistance
Touch current (leakage current)*)

IEC/UL 60950-1
IEC 61010-2-201
PE (Protective Earth) connection required
input to output, 500Vdc
100Vac, 50Hz, TN-,TT-mains / IT-mains
120Vac, 60Hz, TN-,TT-mains / IT-mains
230Vac, 50Hz, TN-,TT-mains / IT-mains
110Vac, 50Hz, TN-,TT-mains / IT-mains
132Vac, 60Hz, TN-,TT-mains / IT-mains
264Vac, 50Hz, TN-,TT-mains / IT-mains

double or reinforced insulation

17. 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 2sdown). 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.
Type test

60s

A
2500Vac

B
3000Vac

C
500Vac

Input

Factory test

5s

2500Vac

2500Vac

500VacL
N

Field test

5s

2000Vac

2000Vac

500VacCut-off current setting

> 4mA

> 4mA

> 4mA

Fig. 17-1 Dielectric strength

B

OutputA
Earth, PE+C-

To fulfil the PELV requirements according to EN60204-1 § 6.4.1, werecommend 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.

Nov. 2023 / Rev. 2.5 DS-QS3.241-EN
All parameters are specified at 24V, 3.4A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0 Germany

16/27

QS3.241
24V, 3.4A, SINGLE PHASE INPUT

Q-Series

18. APPROVED, FULFILLED OR TESTED STANDARDSUL 508

IEC 61010-2-20

IEC 60950-1

UL 60950-1

Class I Div 2

MarineMarineSEMI F47

IEC 60068-2-60

ISA-71.04 G3

LABS

UL Certificate
Listed equipment for category NMTR - Industrial Control Equipment
Applicable for US and Canada
E-File: E198865
Manufacturer's Declaration
Electrical Equipment for Measurement, Control and Laboratory Use - Particularrequirements for control equipment
CB Scheme Certificate
General safety requirements for Information Technology Equipment (ITE)UL Certificate
Recognized component for category QQGQ - Information Technology Equipment (ITE)
Applicable for US and Canada
E-File: E137006
CSA Certificate
Power Supplies for Hazardous Location
Applicable for Canada and US
CSA Class: 5318-01 (Canada), 5318-81 (USA)
Temperature Code: T4
Groups: A, B, C and D
DNV Certificate
DNV Type approved product
Certificate: TAA00002JT
ABS Design Assessment Certificate
ABS (American Bureau of Shipment) assessed product
Certificate: 17-HG1599236-PDA
Test Report
Voltage Sag Immunity for Semiconductor Processing Equipment
Tested for AC 120V and 208V L-L or L-N mains voltages, nominal output voltage andnominal output load
Manufacturer's Declaration (Online Document)
IEC 60068-2-60 - Environmental Tests, Flowing Mixed Gas Corrosion Test
Test Ke - Method 4
H2S: 10ppb
NO2: 200ppb
Cl2: 10ppb
SO2: 200ppb
Test Duration: 3 weeks, which simulates a service life of at least 10 years
Manufacturer's Declaration (Online Document)
Airborne Contaminants Corrosion Test
Severity Level: G3 Harsh
H2S: 100ppb
NOx: 1250ppb
Cl2: 20ppb
SO2: 300ppb
Test Duration: 3 weeks, which simulates a service life of at least 10 years.
Paint Wetting Impairment Substances Test (or LABS-Test)
Tested for Zone 2 and test class C1 according to VDMA 24364-C1-L/W for solvents
and water-based paints

Nov. 2023 / Rev. 2.5 DS-QS3.241-EN
All parameters are specified at 24V, 3.4A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0 Germany

17/27

QS3.241
24V, 3.4A, SINGLE PHASE INPUT

Q-Series

19. REGULATORY PRODUCT COMPLIANCE
EU Declaration of Conformity

The CE mark indicates conformance with the- EMC directive- Low-voltage directive (LVD)- RoHS directive

REACH Regulation (EU)Manufacturer's Statement
EU regulation regarding the Registration, Evaluation, Authorisation andRestriction of Chemicals (REACH) fulfilled.

WEEE Regulation

Manufacturer's Statement
EU-Regulation on Waste Electrical and Electronic Equipment (WEEE)
registered in Germany as business to business (B2B) products.
WEEE Reg.-Nr. DE 555837529

Nov. 2023 / Rev. 2.5 DS-QS3.241-EN
All parameters are specified at 24V, 3.4A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0 Germany

18/27

QS3.241
24V, 3.4A, SINGLE PHASE INPUT

Q-Series

20. PHYSICAL DIMENSIONS AND WEIGHT
WeightDIN rail

Installation Clearances

440g
Use 35mm DIN rails according to EN 60715 or EN 50022 with a height of 7.5 or 15mm.
The DIN rail depth must be added to the unit depth (102mm) to calculate the total required installation
depth.
See chapter 2

Fig. 20-1 Front viewFig. 20-2 Side viewNov. 2023 / Rev. 2.5 DS-QS3.241-EN
All parameters are specified at 24V, 3.4A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0 Germany

19/27

QS3.241
24V, 3.4A, SINGLE PHASE INPUT

Q-Series

21. ACCESSORIES

21.1. ZM1.WALL - WALL MOUNTING BRACKETThis bracket is used to mount the power
supply onto a flat surface without utilizing a DIN rail.

21.2. ZM11.SIDE - SIDE MOUNTING BRACKETThis bracket is used to mount Dimension units 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

Nov. 2023 / Rev. 2.5 DS-QS3.241-EN
All parameters are specified at 24V, 3.4A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0 Germany

20/27

QS3.241
24V, 3.4A, SINGLE PHASE INPUT

Q-Series

21.3. 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 thehold-up time after turn-off of the AC power. In
Power
Buffertimes when the power supply provides sufficient
Load
AC
SupplyUnit(s)voltages, the buffer unit stores energy in+integrated electrolytic capacitors. In case of mains
DC
voltage fault, this energy is released again in a
regulated process. One buffer module can deliver
20A additional current.
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.

21.4. YRM2.DIODE REDUNDANCY MODULEThe YRM2.DIODE is a dual redundancy module, which has two diodes as
decoupling devices included. It canbe used for various purposes. The
most popular application is toconfigure highly reliable and true
redundant power supply systems.
Another interesting application is
the separation of sensitive loads
from non-sensitive loads. Thisavoids the distortion of the power
quality for the sensitive loads which
can cause controller failures.

FailureMonitor++ - 24V,3.4A

QS3.241
Power
SupplyL N PE++ - -+ - + IN 1 IN 2 IN 1 IN 2
YRM2.DIODE

Redundancy Module

Output

24V,3.4A

QS3.241
Power
SupplyL N PE+ -optionalI

I

24V,3.4A
Load
L
N
PE

Nov. 2023 / Rev. 2.5 DS-QS3.241-EN
All parameters are specified at 24V, 3.4A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0 Germany

21/27

QS3.241
24V, 3.4A, SINGLE PHASE INPUT

Q-Series

22. APPLICATION NOTES
22.1. 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 arepeated 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 chapter)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. 22-2) to check if the average output current is below the nominal current.
Fig. 22-1 Repetitive pulse loads, definitions

Fig. 22-2 Max. duty cycle curve

1.0

PPEAK TPEAK

DutyCycle

P0 = 10%
P0 = 50%
P0 = 75%

0.8

T0

max.
150%

0.6

100%

0.4

P0

P0 = 100%

0.2

PPEAK

0
100

P0
PPEAK
T0
TPEAK

Example:Base load (W)Pulse load (above 100%)
Duration between pulses (s)Pulse duration (s)110DutyCycle =

T0 =

120

130

140

150%

Tpeak
Tpeak + T0

Tpeak - (DutyCycle x Tpeak)
DutyCycle

A load is powered continuously with 40W (= 50% of the rated output load). From time to time a peak power of 120W (=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 PPEAK = 150% and a horizontal line where the vertical line crosses the P0 = 50% curve. Read themax. duty cycle from the duty cycle-axis (= 0.37)- Calculate the required pause (base load) length T0:- Result: The required pause length = 1.7s

T0=

Tpeak - (DutyCycle x Tpeak)- Max. repetition rate = pulse +pause length = 2.7s

DutyCycle=

1s- (0.37 x 1s)
0.37

=1.7s

More examples for pulse load compatibility:
PPEAK
120W
120W
100W

P0
80W
0W
40W

TPEAK
1s
1s
1s

T0
>25s
>1.3s
> 0.75s

PPEAK
120W
120W
120W

P0
40W
40W
40W

TPEAK
0.1s
1s
3s

T0
>0.16s
>1.6s>4.9s

Nov. 2023 / Rev. 2.5 DS-QS3.241-EN
All parameters are specified at 24V, 3.4A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0 Germany

22/27

QS3.241
24V, 3.4A, SINGLE PHASE INPUT

Q-Series

22.2. PEAK CURRENT CAPABILITY
Solenoids, contactors and pneumatic modules often have a steady state coil and a pick-up coil. The inrush current demand of the pickup coil is several times higher than the steady-state current and usually exceeds the nominal output current (including the PowerBoost).
The same situation applies when starting a capacitive load.
Branch circuits are often protected with circuit breakers or fuses. In case of a short or an overload in the branch circuit, the fuse needs acertain amount of over-current to trip or to blow. The peak current capability ensures the safe operation of subsequent circuit breakers.
Assuming the input voltage is turned on before such an event, the built-in large sized output capacitors inside the power supply candeliver extra current. Discharging this capacitor causes a voltage dip on the output. The following two examples show typical voltage
dips:Fig. 22-3 Peak load with 2x the nominal current for 50ms,
typ.

OutputVoltage

24V

Fig. 22-4 Peak load with 4x the nominal current for 5ms,
typ.

24V
OutputVoltage

18.5V
6.8A

13.5A

OutputCurrent

0A

7.5V
OutputCurrent

0A
1ms/DIV

10ms/DIVPeak load 6.8A (resistive) for 50ms
Output voltage dips from 24V to 18.5V.

Peak load 13.5A (resistive) for 5ms
Output voltage dips from 24V to 7.5V.

22.3. BACK-FEEDING LOADS
Loads such as decelerating motors and inductors can feed voltage back to the power supply. This feature is also called return voltage
immunity or resistance against Back- E.M.F. (Electro Magnetic Force).
This power supply is resistant and does not show malfunctioning when a load feeds back voltage to the power supply. It does not matter
whether the power supply is on or off.
The maximum allowed feed-back-voltage is 35Vdc. The absorbing energy can be calculated according to the built-in large sized output
capacitor which is specified in chapter 6.

22.4. 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 anampacity 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 6A C-Characteristic breaker should be used

Nov. 2023 / Rev. 2.5 DS-QS3.241-EN
All parameters are specified at 24V, 3.4A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0 Germany

23/27

QS3.241
24V, 3.4A, SINGLE PHASE INPUT

Q-Series

22.5. CHARGING OF BATTERIESThe power supply 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 power supply and the battery.

c)Ensure that the output current of the power supply 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. 6.3mA when the power supply is switched off (except incase a blocking diode is utilized).

22.6. PARALLEL USE TO INCREASE OUTPUT POWER

Unit A

Power supplies from the same series (Q-Series) can be paralleled to increase the output
power. The output voltage shall be adjusted to the same value (±100mV) with the sameload conditions on all units, or the units can be left with the factory settings.

AC

+
-

DC

If more than three units are connected in parallel, a fuse or circuit breaker with a rating of
4A or 6A is required on each output. Alternatively, a diode or redundancy module can also
be utilized.

+

Unit B

Load

AC

+

-

Keep an installation clearance of 15mm (left / right) between two power supplies andavoid installing the power supplies on top of each other. Do not use power supplies inDCparallel in mounting orientations other than the standard mounting orientation (input
terminals on bottom and output terminals on the top of the unit) or in any other condition where a derating of the output current isrequired (e.g. altitude, above 60°C, …).
Pay attention that leakage current, EMI, inrush current, harmonics will increase when using multiple power supplies.

22.7. PARALLEL USE FOR REDUNDANCYPower supplies 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 power supply unit fails. The simplest way
is to put two power supplies in parallel. This is called a 1+1 redundancy.
In case one power supply unit fails, the other one is automatically able tosupport 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 3.4A are paralleled to build a 13.6A
redundant system. For N+1 redundancy the same restrictions apply as forincreasing the output power, see also chapter 22.6.
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 thepower supply. In such a case, the defective unit becomes a load for theother power supplies and the output voltage can not be maintained any
more. This can be avoided by utilizing decoupling diodes which are

FailureMonitor++ - 24V,3.4A

QS3.241
Power
SupplyL N PE++ - -+ - + IN 1 IN 2 IN 1 IN 2
YRM2.DIODE

Redundancy Module

Output

24V,3.4A

QS3.241
Power
SupplyL N PE+ -optionalI

I

24V,3.4A
Load
L
N
PE

Nov. 2023 / Rev. 2.5 DS-QS3.241-EN
All parameters are specified at 24V, 3.4A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0 Germany

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QS3.241
24V, 3.4A, SINGLE PHASE INPUT

Q-Series

included in the redundancy module YRM2.DIODE.
Recommendations for building redundant power systems:
a)
b)
c)

Use separate input fuses for each power supply.
Monitor the individual power supply units. Therefore, use the Input-OK relay contact of the YRM2.DIODE redundancy module.
It is desirable to set the output voltages of all units to the same value (± 100mV) or leave it at the factory setting.

22.8. DAISY CHAINING OF OUTPUTS
Daisy chaining (jumping from one power supply output to the next) is allowed as long as the average output current through one
terminal pin does not exceed 13A. If the current is higher, use a separate distribution terminal block as shown in Fig. 22-6.
Fig. 22-5 Daisy chaining of outputs

Fig. 22-6 Using distribution terminals

max 13A!

OutputOutput

+ + -

+ + -

-

-

+

-

Load

OutputOutput

+ + -

+ + -

-

-

Power
SupplyPower
SupplyPower
SupplyPower
Supply

Input

Input

Input

Input

22.9. SERIES OPERATION

+

-

Load

Distribution
Terminals

Unit AACPower supplies 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 theoutput voltage does not exceed 150Vdc. Voltages with a potential above 60Vdc are not
SELV anymore and can be dangerous. Such voltages must be installed with a protection
against touching.

DC+

Unit BAC

Earthing of the output is required when the sum of the output voltage is above 60Vdc.
Avoid return voltage (e.g. from a decelerating motor or battery) which is applied to the
output terminals.

+
-

DC

Load

+
-

Earth
(see notes)

Keep an installation clearance of 15mm (left / right) between two power supplies and avoid installing the power supplies on top of eachother. Do not use power supplies in series in mounting orientations other than the standard mounting orientation (input terminals onbottom and output terminals on the top of the unit).
Pay attention that leakage current, EMI, inrush current, harmonics will increase when using multiple power supplies.

22.10. INDUCTIVE AND CAPACITIVE LOADSThe unit is designed to supply any kind of loads, including unlimited capacitive and inductive loads.

Nov. 2023 / Rev. 2.5 DS-QS3.241-EN
All parameters are specified at 24V, 3.4A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0 Germany

25/27

QS3.241
24V, 3.4A, SINGLE PHASE INPUT

Q-Series22.11. OPERATION ON TWO PHASESPower Supply
L1
240V +15% max.

The power supply can also be used on two-phases of a three-phase-system. Such aphase-to-phase connection is allowed as long as the supplying voltage is below
240V+15%. Use a fuse or a circuit breaker to protect the N input. The N input isinternally not protected and is in this case connected to a hot wire. Appropriate fuses or
circuit breakers are specified in chapter 22.4 “External Input Protection”.

L3

AC
L
Fuse

internal
fuse

N
PE

L2

DC

22.12. USE IN A TIGHTLY SEALED ENCLOSURE
When the power supply 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 power supply.
The following measurement results can be used as a reference to estimate the temperature rise inside the enclosure.
The power supply is placed in the middle of the box, no other heat producing items are inside the box
Enclosure:
Load:
Input:
Temperature inside enclosure:
Temperature outside enclosure:
Temperature rise:

Rittal Typ IP66 Box PK 9516 100, plastic, 110x180x165mm
24V, 3.4A; (=100%) load is placed outside the box
230Vac
41.3°C (in the middle of the right side of the power supply with a distance of 2cm)
25.1°C
16.2K

Nov. 2023 / Rev. 2.5 DS-QS3.241-EN
All parameters are specified at 24V, 3.4A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0 Germany

26/27

QS3.241
24V, 3.4A, SINGLE PHASE INPUT

Q-Series

22.13. MOUNTING ORIENTATIONSMounting orientations other than input terminals on the bottom and output on the top 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 power
supply. 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. 22-7
Mounting
Orientation A(Standardorientation)

Output Current
OUTPUT

3.5A
2.8
2.1
1.4
0.7
0
10

Power
SupplyINPUT

Fig. 22-8
Mounting
Orientation B(Upside down)

20

30

40

50

60°C

INPUT

3.5A
2.8
2.1
1.4
0.7
0
10

A2
A1

Ambient Temperature

20

30

40

50

60°C

Pow er
SupplyOUTPUT

Output Current

3.5A
2.8
2.1
1.4
0.7
0
10

A2
A1

Ambient Temperature

20

30

40

50

60°C

Output Current

OUTPUT

Pow er
Supply

INPUT

3.5A
2.8
2.1
1.4
0.7
0
10

A2
A1

Ambient Temperature

20

30

40

50

60°C

INPUT

Pow er
SupplyOutput Current

OUTPUT

Fig. 22-11
Mounting
Orientation E(Horizontal ccw)

Ambient Temperature

Output Current

Fig. 22-9
Mounting
Orientation C(Table-top
mounting)

Fig. 22-10
Mounting
Orientation D(Horizontal cw)

A1

3.5A
2.8
2.1
1.4
0.7
0
10

A2
A1

Ambient Temperature

20

30

40

50

60°C

Nov. 2023 / Rev. 2.5 DS-QS3.241-EN
All parameters are specified at 24V, 3.4A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0 Germany

27/27