QT40.241, QT40.242
24V, 40A, THREE PHASE INPUT

Q-Series

POWER SUPPLY
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PRODUCT DESCRIPTION

3AC 380-480V wide-range input
Three input fuses included
Version with extra long lifetime available
Width only 110mm, weight only 1.5kg
95.3% full load and excellent partial load efficiencies
50% BonusPower, 1440W for up to 4s
110A peak current for 10ms for easy fuse tripping
Active PFC (power factor correction)
Active filtering of input transients
Negligible low input inrush current surge
Full power between -25°C and +60°C
Current sharing feature for parallel use
Internal data logging for troubleshooting included
Remote control of output voltage
DC-OK relay contact
Shut-down input
3 Year warranty

SHORT-FORM DATA

The most outstanding features of the DIMENSION
Q- Series DIN rail power supplies are the extremely highefficiencies and the small sizes, which are achieved by asynchronous rectification and other technological designs.

Output voltage
Adjustment range
Output current

Large power reserves of 150% support the starting of heavyloads such as DC-motors or capacitive loads. In many cases thisallows the use of a unit from a lower wattage class which saves
space and money.

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, the three input fuses
and near zero input inrush current make installation and usage
simple. Diagnostics are easy due to the DC-OK relay, a green DCOK LED and the red overload LED.
A large international approval package for a variety of
applications makes this unit suitable for nearly every
application.

ORDER NUMBERS

Mains frequency
AC Input current
Power factor
AC Inrush current

DC 24V24 - 28V
40 – 34.3A
60 – 51.5A
960W
1440W
< 100mVpp
3AC 380-480V
3AC 480V
50-60Hz1.58 / 1.3A
0.92 / 0.93
4.5 / 4.5Apeak

Efficiency
Power losses
Temperature range
Derating
Hold-up time
Dimensions (wxhxd)
Weight95.3 / 95.2%
47.3 / 48.4W-25°C to +70°C
24W/°Ctyp. 25 / 25ms
110x124x127mm
1500g

Output ripple
AC Input voltage

nominalfactory setting 24.1V
continuous
short term (4s)continuous
short term (4s)20Hz to 20MHz-15%/+10%+20% max. 5s±6%at 3x400 / 480Vac
at 3x400 / 480Vac
at 3x400 / 480Vac,
temp. independent
at 3x400 / 480Vac
at 3x400 / 480Vac
operational+60 to +70°C
at 3x400 / 480Vac
without DIN rail

MAIN APPROVALSPower Supply

QT40.241
QT40.242

24-28V Standard unit
24-28V Standard unit
extra long lifetime

Accessory

ZM2.WALL
UF20.241
YR80.241

Wall mount bracket
Buffer unit
Redundancy module

For details and the complete approval list, see chapter 22.

UL 61010

MarineAug. 2024 / Rev. 3.1 DS-QT40.241-EN
All parameters are specified at 24V, 40A, 3x400Vac, +25°C ambient and after a 5 minutes run-in time unless otherwise noted.

1/30
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24V, 40A, THREE PHASE INPUT

Q-Series

INDEX
Page
1. Intended Use ................................................................ 3
2. Installation Instructions ................................................ 3
3. AC Input........................................................................ 4
4. Input Inrush Current ..................................................... 5
5. DC Input ....................................................................... 5
6. Output .......................................................................... 6
7. Hold-up Time ................................................................ 8
8. DC-OK Relay Contact .................................................... 99. Shut-down Input .......................................................... 9
10. Remote Control of Output Voltage ............................ 10
11. Internal Data Logging ................................................. 10
12. Efficiency and Power Losses ....................................... 11
13. Lifetime Expectancy and MTBF .................................. 12
14. Functional Diagram .................................................... 13
15. Terminals and Wiring ................................................. 14
16. Front Side and User Elements .................................... 15
17. EMC ............................................................................ 16
18. Environment ............................................................... 17
19. Protection Features .................................................... 18
20. Safety Features........................................................... 18
21. Dielectric Strength ...................................................... 19
22. Approved, Fulfilled or Tested Standards .................... 20

Page
23. Regulatory Product Compliance ................................ 20
24. Physical Dimensions and Weight ............................... 21
25. Accessories................................................................. 2225.1. ZM2.WALL - Wall mounting bracket ................ 2225.2. UF20.241 - Buffer module ................................ 2225.3. YR80.241 - Redundancy Module ...................... 23
26. Application Notes....................................................... 24
26.1. Repetitive Pulse Loading .................................. 24
26.2. Peak Current Capability .................................... 25
26.3. External Input Protection ................................. 25
26.4. Using only 2 Legs of a 3-Phase System ............. 26
26.5. Charging of Batteries ........................................ 27
26.6. Output Circuit Breakers .................................... 27
26.7. Parallel Use to Increase Output Power ............ 28
26.8. Parallel Use for Redundancy ............................ 28
26.9. Series Operation ............................................... 29
26.10. Inductive and Capacitive Loads ........................ 29
26.11. Back-feeding Loads .......................................... 29
26.12. Use in a Tightly Sealed Enclosure ..................... 29
26.13. Mounting Orientations ..................................... 30

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 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 400V

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)

400VacA 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 indicate flexibility of choice with no implied preference.

shall

A key word indicate a mandatory requirement.

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

Aug. 2024 / Rev. 3.1 DS-QT40.241-EN
All parameters are specified at 24V, 40A, 3x400Vac, +25°C ambient and after a 5 minutes run-in time unless otherwise noted.

2/30
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24V, 40A, THREE 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, 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 a minimum
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. Unused screw terminals
should be securely tightened.
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 enclosure does not provide protection against spilled liquids.
The device is designed for overvoltage category II zones. Below 4000m 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, grounding of one phase is allowed. The continuous voltage between the
input terminals and the PE potential must not exceed 528Vac.
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 adjacent device is a heat source. When the device is permanently loaded with less than 50%, the 5mm can be reduced to zero.
The device is designed, tested and approved for branch circuits up to 32A (IEC) and 30A (UL) without additional protection device. If an externalfuse is utilized, do not use circuit breakers smaller than 6A B- or 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 temperatureand is defined 2cm below the device.
The device is designed to operate in areas between 5% and 95% relative humidity.

Aug. 2024 / Rev. 3.1 DS-QT40.241-EN
All parameters are specified at 24V, 40A, 3x400Vac, +25°C ambient and after a 5 minutes run-in time unless otherwise noted.

3/30
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24V, 40A, THREE PHASE INPUT

Q-Series

3. AC INPUT
AC inputnom.

3AC 380-480V

nom.
typ.
typ.

3x 323-528Vac
3x 528-576Vac
50–60Hz3x 305Vac
3x 275Vac

Input current

typ.

3AC 400V
1.58A

3AC 480V
1.3A

Power factor*)
Start-up delay
Rise time

typ.
typ.
typ.
typ.
max.

0.92
500ms
35ms
40ms
500mV

0.93
600ms
35ms
40ms
500mV

AC input range
Input frequency
Turn-on voltage
Shut-down voltage

Turn-on overshoot*)suitable for TN, TT and IT mains networks,
grounding of one phase is allowed
continuous operation
short-time up to 5s±6%steady-state value, load independent, see Fig. 3-1
steady-state value, load independent, see Fig. 3-1

at 24V, 40A, symmetrical phase voltages,
see Fig. 3-3
at 24V, 40A, see Fig. 3-4
see Fig. 3-2
at 24V, 40A, resistive load, 0mF see Fig. 3-2
at 24V, 40A, resistive load, 40mF 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

Fig. 3-1 Input voltage range

POUT

Fig. 3-2 Turn-on behaviour, definitions

Input
Voltage

Rated input range
max 5s

VIN
275V 305V

323V

OutputVoltageStart-up
delay

Rise
Time

528V 576Vac

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

Fig. 3-4 Power factor vs. output load at 24V

Input Current, typ.

0.95

1.6A
1.4
1.2
1.0
0.8
0.6
0.4
0.2

- 5%

OvershootTurn-onShut -dow n

L1 L2 L3

Power Factor, typ.
B

A: 3x 400Vac
B: 3x 480Vac

A

0.90

A

0.85

B

A: 3x 400Vac
B: 3x 480Vac

0.80
0.75
Output Current

04

8 12 16 20 24 28 32 36 40A

Output Current

0.70
4

8 12 16 20 24 28 32 36 40A

Aug. 2024 / Rev. 3.1 DS-QT40.241-EN
All parameters are specified at 24V, 40A, 3x400Vac, +25°C ambient and after a 5 minutes run-in time unless otherwise noted.

4/30
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24V, 40A, THREE PHASE INPUT

Q-Series

4. INPUT INRUSH CURRENT
The power supply is equipped with an active inrush current limitation circuit, which limits the input inrush current after turn-on to anegligible low value. The input current is usually smaller than the steady-state input current.

Inrush current*)

max.
typ.
max.
typ.

Inrush energy
Inrush delay*)

3AC 400V
6Apeak
4.5Apeak
1.5A2s500ms

3AC 480V
6Apeak
4.5Apeak
1.5A2s
600ms

over entire temperature range
over entire temperature range
over entire temperature range

The charging current into EMI suppression capacitors is disregarded in the first microseconds after switch-on.

Fig. 4-1 Typical turn-on behaviour at nominal load and+25°C ambient temperature

Input Current 2A/DIV

Input
3x400Vac

Output100ms/DIV

24Vdc

5. DC INPUT
Do not operate this power supply with DC input voltage.

Aug. 2024 / Rev. 3.1 DS-QT40.241-EN
All parameters are specified at 24V, 40A, 3x400Vac, +25°C ambient and after a 5 minutes run-in time unless otherwise noted.

5/30
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24V, 40A, THREE 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.
typ.
typ.
max.
max.
typ.

24V
24-28V
30V***)
24.1V
24.1V
25.1V
10mV
50mV
1000mV

max.
nom.
nom.
nom.

100mVpp
40A
34.3A
60A

nom.

51.5A

typ.

110A

nom.
nom.
typ.
typ.

960W
1440W*)
4s
7scont. current
40A
44A
60A
68A
46A
51A
190A
10 200µF

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

guaranteed
at clockwise end position of potentiometer±0.2%, at full load, cold unit, in “single use” mode
±0.2%, at full load, cold unit, in “parallel use” modeat no load, cold unit, in “parallel use” mode
3x323-576Vac
in “single use” mode: static value, 0A→40A, see Fig. 6-1
in “parallel use” mode: static value, 0A→40A,
see Fig. 6-2
20Hz to 20MHz, 50Ohm
continuously available at 24V, see Fig. 6-1 and Fig. 6-2
continuously available at 28V, see Fig. 6-1 and Fig. 6-2
short term (4s) available BonusPower*), at 24V,
see Fig. 6-1, Fig. 6-2 and Fig. 6-4
short term (4s) available BonusPower*), at 28V,
see Fig. 6-1, Fig. 6-2 and Fig. 6-4
up to 10ms, output voltage stays above 20V, see Fig. 6-4, This
peak current is available once every second.
See chapter 26.2 for more peak current measurements.
continuously available at 24-28V
short term available BonusPower*) at 24-28V
duration until the output voltage dips, see Fig. 6-3
overload free time to reset power manager, see Fig. 6-5
see Fig. 6-1
continuous, load impedance 25mOhm, see Fig. 6-1
continuous, load impedance 25mOhm, see Fig. 6-1
short-term (4s), load impedance 25mOhm, see Fig. 6-1
short-term (4s), load impedance 25mOhm, see Fig. 6-1
continuous, load impedance <10mOhm
continuous, load impedance <10mOhm
up to 10ms, load impedance <10mOhm, see Fig. 6-4
included in 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 26.1. If thepower supply is loaded longer with the BonusPower than shown in the bonus-time diagram (see Fig. 6-3), the max. output power is automatically reduced
to 960W.
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 28.5V.

Aug. 2024 / Rev. 3.1 DS-QT40.241-EN
All parameters are specified at 24V, 40A, 3x400Vac, +25°C ambient and after a 5 minutes run-in time unless otherwise noted.

6/30
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24V, 40A, THREE PHASE INPUT

Q-Series

Fig. 6-1 Output voltage vs. output current in “single use” mode,
typ.
Output Voltage

Output Voltage (Parallel Use, typ.)Adjustment Range

28V
A

Fig. 6-2 Output voltage vs. output current in “paralleluse” mode, typ.

29V

B

24

28V

20

27V

16

26V

A

A Continuously

12

B

A

24V

4
0

A Continuously

23V
22V

0

10

20

30

40

50

60

B

0

70A

B

Factory
setting

25V

available
B Short-term (4s)BonusPower

8

Adjustment Range

available
Short-term (4s)BonusPower

10

20

A

30

B

40

50

60A

Output Current

Output Current

Fig. 6-3 Bonus time vs. output power

Fig. 6-4 Dynamic overcurrent capability, typ.
Output V ol tage (dynamic behavior, < 10ms)

Bonus Time

5s

28V

max.

24
20
16
12

4
min.

3
2
1

Output Power0
100 110 120 130 140 150 160 170%840Adjustment Range

0

40

80

120

160

200A

Output Current

Fig. 6-5 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 after the end of an output short circuit or output overload.
Fig. 6-6 BonusPower after input turn-on

Fig. 6-7 BonusPower after output short

Short ofOutput

Input
Voltage

OutputVoltage
OutputVoltage150%
Output
Power

100%

Bonus
Power

Output
Power

150%

Bonus
Power

100%

Aug. 2024 / Rev. 3.1 DS-QT40.241-EN
All parameters are specified at 24V, 40A, 3x400Vac, +25°C ambient and after a 5 minutes run-in time unless otherwise noted.

7/30
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24V, 40A, THREE PHASE INPUT

Q-Series

7. HOLD-UP TIME
Hold-up Time*)3AC 400V*)
50ms
40ms
25ms
20ms

typ.
min.
typ.
min.

3AC 480V*)
50ms
40ms
25ms
20ms

at 24V, 20A, see Fig. 7-1
at 24V, 20A, see Fig. 7-1
at 24V, 40A, see Fig. 7-1
at 24V, 40A, see Fig. 7-1

Curves and figures for operation on only 2 legs of a 3-phase system can be found in chapter 26.4

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

Fig. 7-2 Shut-down behaviour, definitions

24V, 20A, typ.

50ms

L1 L2 L3

24V, 20A, min.

40
30

24V, 40A, typ.

20

24V, 40A, min.

10
0
320

Input
Voltage

Hold-up Time

Input Voltage

360

400

440

- 5%

OutputVoltage

3x480VacAug. 2024 / Rev. 3.1 DS-QT40.241-EN
All parameters are specified at 24V, 40A, 3x400Vac, +25°C ambient and after a 5 minutes run-in time unless otherwise noted.

8/30
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24V, 40A, THREE PHASE INPUT

Q-Series

8. DC-OK RELAY CONTACT
This feature monitors the output voltage, which is produced by the power supply itself. It is independent of a back-fed voltage from aunit connected in parallel to the power supply output.
Contact closes
Contact opens

As soon as the output voltage reaches 90% of the adjusted output voltage.
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.
As soon as the output voltage exceeds 90% of the adjusted voltage.
max
60Vdc 0.3A, 30Vdc 1A, 30Vac 0.5A
resistive loadmin
1mA at 5Vdc
min. permissible load
See dielectric strength table in chapter 21.

Contact re-closes
Contact ratings
Isolation voltage

Fig. 8-1 DC-OK relay contact behavior
VOUT = VADJ
10%

<
1ms

open

0.9* VADJ

>
1ms

250ms

closedopen

closed

9. SHUT-DOWN INPUTThis feature allows a switch-off of the output of the power supply with a signal switch or an external voltage. The shut-down occurs
immediately while the turn-on is delayed up to 350ms. In a shut-down condition, the output voltage is <2V and the output power is<0.5W.
The voltage between different minus pole output terminals must be below 1V when units are connected in parallel. In a series operationof multiple power supplies only wiring option “A” with individual signal switches is allowed.
Please note:- Option C requires a current sink capability of the voltage source. Do not use a blocking diode.
- The shut-down function has no safety feature included.
- Please be aware, that shutting-down the device very often could result in reduction of product lifetime. We recommend staying
below 50 shut-down cycles per day.
Fig. 9-1 Activation of the shut-down input

Option A:

Option B:
15 Shutdown
16 Input

OFF: linked
ON : open(via open
collector)n.c.
I

15 Shutdown
16 Input

Option C:(via external
voltagen.c.

15 Shutdown
16 Input+

OFF: I > 0.3mA
ON : I < 0.1mA-

U
OFF: U < 1V
ON : U = 4 -29V-

Aug. 2024 / Rev. 3.1 DS-QT40.241-EN
All parameters are specified at 24V, 40A, 3x400Vac, +25°C ambient and after a 5 minutes run-in time unless otherwise noted.

9/30
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24V, 40A, THREE PHASE INPUT

Q-Series

10. REMOTE CONTROL OF OUTPUT VOLTAGE
The shut-down input can also be used to remotely adjust the output voltage between typically 14Vdc and 28Vdc.
Please be aware, that repeatedly changing the output voltage of more than 4V reduces the lifetime. We recommend not adjusting theoutput voltage more than 50 times per day when the adjustment is larger than 4V.
Fig. 10-1 Remote control of the output voltage

Fig. 10-2 Applying the control voltage

Output Voltage

28V
26V
24V
22V
20V
18V
16V
14V
12V
0V

Potentiometer:
set to 28V
set to 24V

Control
Voltagemin. 0V
max. +50V+

n.c.

15 Shutdown
16 Input

5V

10V

15V

20V

Control Voltage

Instructions:
1. Set the unit into “Single Use” mode.
2. Set the output voltage adjustment (24-28V) to the maximum desired voltage.
3. Apply a control voltage between pin 15 and main ground (negative output voltage).

11. INTERNAL DATA LOGGING
A protected microcontroller inside the power supply acquires and stores operating data during the life of the unit. The data can be
downloaded with a small tool and a special software by the PULS service and repair personnel, even when the unit is defect. The data
allows for better troubleshooting. Analysis of what happened before a failure can be determined much more accurately.
The data will be acquired with a fixed sampling rate unless the peak detectors do trigger due to an abnormal condition. In such cases,
the abnormal condition will be captured.
Acquired data:- Family name of unit (QT40), revision of firmware- Operational hours and expired portion of lifetime- Operational data; latest 60 values with timestamps of the last 158 minutes of:
Number of overvoltage transients,
Average input voltage,
Peak input voltage,
Inside temperature,
Overloads > 2s,
Missing of one input phase (minimum output load required)- Failure data; various errors such as:
Internal errors,
Overtemperature shut-down,
OVP,
Long-term overloads,
Shut-down due too high input voltage,
Loss or too low voltage of one leg of the three phase system- Number of turn-on sequences and overvoltage transients- Highest temperature value with timestamp
Aug. 2024 / Rev. 3.1 DS-QT40.241-EN
All parameters are specified at 24V, 40A, 3x400Vac, +25°C ambient and after a 5 minutes run-in time unless otherwise noted.

10/30
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24V, 40A, THREE PHASE INPUT

Q-Series

12. EFFICIENCY AND POWER LOSSES
Efficiencies for 3-phase operation:
Efficiency
Average efficiency*)
Power losses*)

3AC 400V
95.3%
94.7%
1.5W
9.5W
24.1W
47.3W

typ.
typ.
typ.
typ.
typ.
typ.

3AC 480V
95.2%
94.6%
1.5W
9.8W
25.0W
48.4W

at 24V, 40A
25% at 10A, 25% at 20A, 25% at 30A, 25% at 40A
with activated shut-down
at 24V, 0A (no load)
at 24V, 20A (half load)
at 24V, 40A (full load)

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. 12-1 Efficiency vs. output current at 24V, typ.

Fig. 12-2 Losses vs. output current at 24V, typ.

Efficiency

Power Losses

96%

3x400Vac

60W
3x480Vac50953x480Vac

94

40
3x400Vac

30
20

93

10
Output Current

928Output Current

0

12 16 20 24 28 32 36 40A

Fig. 12-3 Efficiency vs. input voltage at 24V, 40A, typ.

0

4

8 12 16 20 24 28 32 36 40A

Fig. 12-4 Losses vs. input voltage at 24V, 40A, typ.

Efficiency

Power Losses

95.5%

50W

95.4

49

95.3

48

95.2

47

95.1

46

95.0
94.9
350

45
Input Voltage

400

450

500 3x550Vac

44
350

Input Voltage

400

450

500 3x550Vac

Aug. 2024 / Rev. 3.1 DS-QT40.241-EN
All parameters are specified at 24V, 40A, 3x400Vac, +25°C ambient and after a 5 minutes run-in time unless otherwise noted.

11/30
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24V, 40A, THREE PHASE INPUT

Q-Series

13. LIFETIME EXPECTANCY AND MTBF
QT40.241
Calculated lifetime expectancy*)

3AC 400V
69 000h86 000h
114 000h
196 000h*)
244 000h*)
322 000h*)

3AC 480V
66 000h81 000h
112 000h
186 000h*)
230 000h*)
316 000h*)

at 24V, 40A and +40°C
at 24V, 32A and +40°C
at 24V, 20A and +40°C
at 24V, 40A and +25°C
at 24V, 32A and +25°C
at 24V, 20A and +25°C

QT40.242
Calculated lifetime expectancy*)

3AC 400V
93 000h
132 000h
168 000h*)
262 000h*)
373 000h*)
475 000h*)

3AC 480V
91 000h
128 000h
167 000h*)
258 000h*)
363 000h*)
472 000h*)

at 24V, 40A and +40°C
at 24V, 32A and +40°C
at 24V, 20A and +40°C
at 24V, 40A and +25°C
at 24V, 32A and +25°C
at 24V, 20A and +25°C

QT40.241, QT40.242
MTBF**) SN 29500, IEC 61709

3AC 400V
375 000h
685 000h
158 000h
211 000h

3AC 480V
369 000h
678 000h
157 000h
210 000h

at 24V, 40A and +40°C
at 24V, 40A and +25°C
at 24V, 40A and +40°C; Ground Benign GB40
at 24V, 40A and +25°C; Ground Benign GB25

MTBF**) MIL HDBK 217F*)

The calculated lifetime expectancy shown in the table indicates the minimum operating hours (service lifetime) and is determined by the lifetime expectancyof 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 lifetime of up to 15 years (131 400h). Any number exceeding thisvalue is a calculated theoretical lifetime which can be used to compare devices.
**) MTBF stands for Mean Time Between Failures, 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.

Aug. 2024 / Rev. 3.1 DS-QT40.241-EN
All parameters are specified at 24V, 40A, 3x400Vac, +25°C ambient and after a 5 minutes run-in time unless otherwise noted.

12/30
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24V, 40A, THREE PHASE INPUT

Q-Series

14. FUNCTIONAL DIAGRAM
Fig. 14-1 Functional diagram

Single /Parallel

Outpu tVoltage
Regulator

L1
L2
L3

Input Fuses
Input Filter
Input Rectifier
Inrush LimiterTransient Filter

Temperature
Shutdown

PFC Converter

OutputPower
Manager

OutputOverVoltage
Protection

Power
Converter

OutputVoltage
Monitor

Outpu tFilterVOU T++
Overload
LED
DC-OK
LED

DC ok
Relay

13

Shutdown

15

14

16

DC-OK
Contact

Shut-down
Inpu tAug. 2024 / Rev. 3.1 DS-QT40.241-EN
All parameters are specified at 24V, 40A, 3x400Vac, +25°C ambient and after a 5 minutes run-in time unless otherwise noted.

13/30
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24V, 40A, THREE PHASE INPUT

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15. TERMINALS AND WIRING
The terminals are IP20 Finger safe constructed and suitable for field and factory wiring.
Type
Solid wire
Stranded wire
American Wire Gauge
Max. wire diameter
Wire stripping length
Screwdriver
Recommended tightening torqueInput
screw terminal
max. 6mm2
max. 4mm2
AWG 20-10
2.8mm(including ferrules)
7mm
4mm slotted or cross-head
No 1
0.8Nm

Outputscrew terminal
max. 16mm2
max. 10mm2
AWG 22-8
5.2mm(including ferrules)
12mm
3.5mm or 5mm slotted or
cross-head No 2
2Nm

DC-OK, Shut-down
spring-clamp terminal
max. 1.5mm2
max. 1.5mm2
AWG 26-14
1.5mm(including ferrules)
7mm
3mm slotted(to open the spring)
not applicable

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) Unused terminal compartments should be securely tightened.
f) Ferrules are allowed.
Daisy chaining:
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 54A. If the current is higher, use a separate distribution terminal block as shown in Fig. 15-2.
Fig. 15-1 Daisy chaining of outputs

Power
Supply+ +- -OutputFig. 15-2 Using distribution terminals

Distribution
Terminals

Power
Supply+ +- -OutputPower
Supply
Load
+

-

+ +

- -

OutputPower
Supply+ +- -OutputLoad+-max 54A!

Aug. 2024 / Rev. 3.1 DS-QT40.241-EN
All parameters are specified at 24V, 40A, 3x400Vac, +25°C ambient and after a 5 minutes run-in time unless otherwise noted.

14/30
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24V, 40A, THREE PHASE INPUT

Q-Series

16. FRONT SIDE AND USER ELEMENTS
Fig. 16-1 Front side

A

B

C

D

E

F

G

H

Input Terminals (Screw terminals)
L1, L2, L3 Line input...PE (Protective Earth) input
Output Terminals (Screw terminals, two pins per pole)+
Positive output–
Negative (return) output“Parallel Use” “Single Use” Selector
Set jumper to “Parallel Use” when power supplies are connected in parallel
to increase the output power. In order to achieve a sharing of the load
current between the individual power supplies, the “parallel use” regulates
the output voltage in such a manner that the voltage at no load is approx.
4% higher than at nominal load. See also chapter 26.7. A missing jumper isequal to a “Single Use” mode.
Output Voltage Potentiometer
Multi turn potentiometer;
Open the flap to set the output voltage.
Factory set: 24.1V at full output current, “Single Use” mode.
DC-OK LED (green)
On, when the voltage on the output terminals is >90% of the adjusted
output voltage
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.
- Flashing, when the shut-down has been activated or the unit has switched
off due to overtemperature.
- Input voltage is required
DC-OK Relay Contact
The DC-OK relay contact is synchronized with the DC-OK LED.
See chapter 8 for details.
Shut-down and Remote-Control Input
Allows the power supply to be shut down. Can be activated with a switch
contact or an external voltage.
The remote-control input allows adjusting the output voltage. See chapter 9
and 10 for details.

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

Overload LED
OFF
OFF
ON
ON
flashing
flashing
OFF

DC-OK LED
ON
ON
OFF
OFF
OFF
OFF
OFF

DC-OK Contact
ClosedClosed
Open
Open
Open
Open
Open

Aug. 2024 / Rev. 3.1 DS-QT40.241-EN
All parameters are specified at 24V, 40A, 3x400Vac, +25°C ambient and after a 5 minutes run-in time unless otherwise noted.

15/30
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24V, 40A, THREE PHASE INPUT

Q-Series

17. EMCThe device is suitable for applications in industrial environment as well as in residential, commercial and light industry environment.
All results assume a three-phase operation of the device.
EMC Immunity
Electrostatic discharge
Electromagnetic RF field
Fast transients (Burst)

Surge voltage on input
Surge voltage on output
Surge voltage on DC-OK
Conducted disturbance
Mains voltage dips
(Dips on three phases)
Mains voltage dips
(Dips on two phases)

Voltage interruptions
Voltage sags

Powerful transients

According generic standards: EN IEC 61000-6-1 and EN IEC 61000-6-2
EN 61000-4-2
contact discharge
8kV
Criterion A
air discharge
15kV
Criterion A
EN 61000-4-3
80MHz-6GHz
10V/m
Criterion A
input lines
4kV
Criterion A
EN 61000-4-4
output lines
2kV
Criterion A
DC-OK signal (coupling clamp)
2kV
Criterion A
EN 61000-4-5
L1 → L2, L2 → L3, L1 → L3
2kV
Criterion A
L1 / L2 / L3 → PE
4kV
Criterion A
EN 61000-4-5+→1kV
Criterion A+ / - → PE
1kV
Criterion A
EN 61000-4-5
DC-OK signal → PE
1kV
Criterion A
EN 61000-4-6
0.15-80MHz
10V
Criterion A
EN 61000-4-11
0% of 380Vac (0Vac)
0Vac, 20ms
Criterion A,
0% of 480Vac (0Vac)
0Vac, 20ms
Criterion A
EN 61000-4-11
40% of 380Vac (152Vac)
200ms
Criterion A
40% of 480Vac (192Vac)
200ms
Criterion A
70% of 380Vac (266Vac)
500ms
Criterion A
70% of 480Vac (336Vac)
500ms
Criterion A
EN 61000-4-11
0Vac
5000msCriterion C
SEMI F47
dips on two phases acc. to chapter 7.2. of the SEMI F47 standard
80% of 380Vac (304Vac)
1000msCriterion A
70% of 380Vac (266Vac)
500ms
Criterion A
50% of 380Vac (160Vac)
200ms
Criterion A
VDE 0160
over entire load range
1550V, 1.3ms
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
Conducted emission
input lines
Conducted emission
output lines

According generic standards: EN IEC 61000-6-3 , EN IEC 61000-6-8 and EN IEC 61000-6-4
EN 55011, EN 55032, FCC Part 15, CISPR 11, CISPR 32
Class B
IEC/CISPR 16-1-2, IEC/CISPR 16-2-1

Limits for DC power ports according EN
IEC 61000-6-3 fulfilled for a maximum
DC output line length of 25m.
Limits for DC power ports according EN
IEC 61000-6-8 fulfilled without
restrictions.
Class Bfulfilled for class A equipment
fulfilled*)

Radiated emission
EN 55011, EN 55032
Harmonic input current
EN 61000-3-2
Voltage fluctuations, flicker
EN 61000-3-3This 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

Aug. 2024 / Rev. 3.1 DS-QT40.241-EN
All parameters are specified at 24V, 40A, 3x400Vac, +25°C ambient and after a 5 minutes run-in time unless otherwise noted.

16/30
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24V, 40A, THREE PHASE INPUT

Q-Series

The power supply has three converters with three different switching frequencies included. One isnearly constant. The others are variable.
105kHzResonant converter, nearly constant
1kHz to 135kHz
Boost converter, load dependent
40kHz to 210kHz
PFC converter, input voltage and load dependent

Switching Frequencies
Switching frequency 1
Switching frequency 2
Switching frequency 3

18. ENVIRONMENT
Operational temperature*)
Storage temperature
Output derating
Humidity**)Vibration sinusoidal-25°C to +70°C-40°C to +85°C
24W/°C
5 to 95% r.H.
2-17.8Hz: ±1.6mm; 17.8-500Hz: 1g***)2 hours / axis
15g 6ms, 10g 11ms***)3 bumps / direction, 18 bumps in total
0 to 2000m
2000 to 5000m

Shock
Altitude

Altitude derating
Overvoltage category

reduce output power according Fig. 18-1
for storage and transportation
between +60°C and +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. 18-2
> 2000m, see Fig. 18-2
IEC/UL 61010-2-201 up to 4000m
IEC/UL 61010-2-201 up to 5000m
IEC/UL 61010-2-201 not conductive

60W/1000m or 5°C/1000m
III
II
2

Degree of pollution*)

Operational temperature is the same as the ambient or surrounding temperature and is defined as the air temperature 2cm below the unit. Curves andfigures for operation on only 2 legs of a 3-phase system can be found in chapter 26.4.
**) Do not energize while condensation is present.
***) Higher levels allowed when using the wall mounting bracket ZM2.WALL

Fig. 18-1 Output current vs. ambient temp.

Fig. 18-2 Output current vs. altitude

Al lowed Output Current at 24V

Al lowed Output Current at 24V

60A

60A

50

50

40

40

30

30

20
10
0

A... Tamb < 60 °C
B... Tamb < 50°C
C... Tamb < 40°C

20
10
-25

0

20

40

60 70°C

Ambient Temperature

0

0

2000

4000 5000m
Al titude

Aug. 2024 / Rev. 3.1 DS-QT40.241-EN
All parameters are specified at 24V, 40A, 3x400Vac, +25°C ambient and after a 5 minutes run-in time unless otherwise noted.

17/30
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24V, 40A, THREE PHASE INPUT

Q-Series

19. PROTECTION FEATURES
Output protection
Output overvoltage protection

Degree of protection

Penetration protection
Overtemperature protection
Input transient protection
Internal input fuse*)

Electronically protected against overload, no-load and short-circuits*)
typ. 30Vdc
In case of an internal power supply defect, a redundant circuit
max. 32Vdc
limits the maximum output voltage. The output shuts down andautomatically attempts to restart.
IP20
EN/IEC 60529
Caution: For use in a controlled environment according to CSA
22.2 No 107.1-01.
> 5mm
e.g. screws, small partsyes
Output shut-down with automatic restart
MOV (Metal Oxide Varistor)
included
not user replaceable

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

20. SAFETY FEATURES
Input / output separation*)

Class of protection
Isolation resistancePE resistance
Touch current (leakage current)

*)

SELV
IEC/UL 61010-2-201
PELV
IEC/UL 61010-2-201
double or reinforced insulation
I
PE (Protective Earth) connection required> 100MOhm
input to output, 500Vdc< 0.1Ohm
typ. 0.35mA / 0.64mA
3x400Vac, 50Hz, TN-,TT-mains / IT-mains
typ. 0.45mA / 0.91mA
3x480Vac, 60Hz, TN-,TT-mains / IT-mains
max. 0.45mA / 0.78mA
3x440Vac, 50Hz, TN-,TT-mains / IT-mains
max. 0.60mA / 1.20mA
3x528Vac, 60Hz, TN-,TT-mains / IT-mains

double or reinforced insulation

Aug. 2024 / Rev. 3.1 DS-QT40.241-EN
All parameters are specified at 24V, 40A, 3x400Vac, +25°C ambient and after a 5 minutes run-in time unless otherwise noted.

18/30
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24V, 40A, THREE PHASE INPUT

Q-Series

21. 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 phase 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
500VacD
500VacFactory test

5s

2500Vac

2500Vac

500Vac

500VacField test

5s

2000Vac

2000Vac

500Vac

500VacCut-off current setting> 10mA> 10mA> 40mA> 1mA

Fig. 21-1 Dielectric strength

Input
L1
L2
L3

DC-ok
B*)

13

14

D

A

Output

Earth
C

+/-

Shut-down
15/16

To fulfil the PELV requirements according to EN 60204-1 § 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.

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. 2024 / Rev. 3.1 DS-QT40.241-EN
All parameters are specified at 24V, 40A, 3x400Vac, +25°C ambient and after a 5 minutes run-in time unless otherwise noted.

19/30
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24V, 40A, THREE PHASE INPUT

Q-Series

22. APPROVED, FULFILLED OR TESTED STANDARDSUL 61010-2-201

IEC 61010-2-201

Marine (DNV)(only QT40.241)
SEMI F47

VDMA 24364

UL Certificate
Listed equipment for category NMTR - Electrical Equipment for
Measurement, Control and Laboratory Use - Particular requirements forcontrol equipment
Applicable for US and Canada
E-File: E198865
CB Scheme Certificate
Electrical Equipment for Measurement, Control and Laboratory Use Particular requirements for control equipment
DNV Certificate
DNV Type approved product
Certificate: TAA00002YX
Test Report
Voltage Sag Immunity for Semiconductor Processing Equipment
Tested for 3AC 400V L-L or L-N mains voltages, nominal output voltage andnominal output load
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

23. REGULATORY PRODUCT COMPLIANCE
EU Declaration of Conformity

REACH Regulation (EU)

WEEE Directive

KC Korean Certification(only QT40.241)

The CE mark indicates conformance with the- EMC directive- Low-voltage directive- RoHS directive
Manufacturer's Declaration
EU regulation regarding the Registration, Evaluation, Authorisation andRestriction of Chemicals (REACH) fulfilled.
EU Regulation (EC) 1907/2006.
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
KC Korean Certificate
Korean - Registration of Broadcasting and Communication Equipment
Registered under Clause3, Article 58-2 of Radio Waves Act.
Registration No. R-R-PUG-QT40_241

Aug. 2024 / Rev. 3.1 DS-QT40.241-EN
All parameters are specified at 24V, 40A, 3x400Vac, +25°C ambient and after a 5 minutes run-in time unless otherwise noted.

20/30
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24V, 40A, THREE PHASE INPUT

Q-Series

24. PHYSICAL DIMENSIONS AND WEIGHT
Width
HeightDepth
WeightDIN rail
Housing material
Installation Clearances

110mm
124mm
127mm
The DIN rail depth must be added to the unit depth to calculate the total required installation depth.
1500g
Use 35mm DIN rails according to EN 60715 or EN 50022 with a height of 7.5 or 15mm.
Body: Aluminium alloy
Cover: Zinc-plated steel
See chapter 2

Fig. 24-1 Front viewFig. 24-2 Side view

Aug. 2024 / Rev. 3.1 DS-QT40.241-EN
All parameters are specified at 24V, 40A, 3x400Vac, +25°C ambient and after a 5 minutes run-in time unless otherwise noted.

21/30
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24V, 40A, THREE PHASE INPUT

Q-Series

25. ACCESSORIES

25.1. ZM2.WALL - WALL MOUNTING BRACKETThis bracket is used to mount specific DIMENSION units
onto a flat surface without utilizing a DIN rail.

25.2. UF20.241 - BUFFER MODULE
This buffer unit is a supplementary device for DC 24V power supplies. It delivers power tobridge typical mains failures or extends the hold-up time after turn-off of the AC power. In
times when the power supply provides sufficient voltages, the buffer unit stores energy inintegrated electrolytic capacitors. In case of mains voltage fault, this energy is released again
in a regulated process. One buffer module can deliver 20A. To buffer the full output current of
40A, two buffer modules are needed in parallel.
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 toincrease the output ampacity or the hold-up time.

AC
DC

Power
SupplyBufferUnit(s)Load+-Aug. 2024 / Rev. 3.1 DS-QT40.241-EN
All parameters are specified at 24V, 40A, 3x400Vac, +25°C ambient and after a 5 minutes run-in time unless otherwise noted.

22/30
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24V, 40A, THREE PHASE INPUT

Q-Series25.3. YR80.241 - REDUNDANCY MODULEThe YR80.241 is equipped with two input channels (40A each), which are individually decoupled by utilizing
MOSFET technology. The output current can go as high as 80A.
Using MOSFETs instead of diodes reduces the heat generation and the voltage drop between input andoutput. The YR80.241 does not require an additional auxiliary voltage and is self-powered even in case of ashort circuit across the output.
Due to the low power losses, the unit is very slender and only requires 46mm width on the DIN rail.

Fig. 25-1 Typical 1+1 Redundant configuration for 40A with a dual redundancy module

24V
40A
Load

QT40
24-28V 960W
Power Supply
DCOK

Single Use

24V, 40A

I

I

I

QT40
24-28V 960W
Power Supply

OutputParallel Use

L1 L2 L3 PE

FailureMonitor+ +- -YR80.241
Redundancy
Module
Input
1

+ -

Parallel Use

DCOKSingle Use

Input
2

24V, 40A+ -L1 L2 L3 PE

I

I

+ +

- -

I

L1
L2
L3
PE

Aug. 2024 / Rev. 3.1 DS-QT40.241-EN
All parameters are specified at 24V, 40A, 3x400Vac, +25°C ambient and after a 5 minutes run-in time unless otherwise noted.

23/30
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24V, 40A, THREE PHASE INPUT

Q-Series

26. APPLICATION NOTES
26.1. 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. 26-2) to check if the average output current is below the nominal current.
d)
The duty cycle must be below or equal 0.5.
Fig. 26-1 Repetitive pulse loads, definitions

PPEAK TPEAK

Fig. 26-2 Max. duty cycle curve

T0

max.
150%
100%

P0

P0
PPEAK
T0
TPEAK

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

T0 =

Tpeak
Tpeak + T0

Tpeak - (DutyCycle x Tpeak)
DutyCycle

A load is powered continuously with 480W (= 50% of the rated output load). From time to time a peak power of 1440W(= 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
1440W
1440W
1200W

P0
960W
0W
480W

TPEAK
1s
1s
1s

T0
>25s
>1.3s
> 0.75s

PPEAK
1440W
1440W
1440W

P0
480W
480W
480W

TPEAK
0.1s
1s
3s

T0
>0.16s
>1.6s>4.9s

Aug. 2024 / Rev. 3.1 DS-QT40.241-EN
All parameters are specified at 24V, 40A, 3x400Vac, +25°C ambient and after a 5 minutes run-in time unless otherwise noted.

24/30
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24V, 40A, THREE PHASE INPUT

Q-Series

26.2. PEAK CURRENT CAPABILITY
The power supply 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 (including the BonusPower). 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 breakerneed a certain amount of overcurrent to open in a timely manner. This avoids voltage loss in adjacent circuits.
The extra current (peak current) is supplied by the power converter and the built-in large sized output capacitors of the power supply.
The capacitors get discharged during such an event, which causes a voltage dip on the output. The following two examples show typicalvoltage dips:
Fig. 26-3 Peak load with 2x the nominal current for 50ms,
typ.

OutputVoltage

24V
80A

Fig. 26-4 Peak load with 5x the nominal current for 5ms,
typ.

200A

19V
OutputCurrent

0A

OutputVoltage

24V

17V
OutputCurrent

0A

10ms/DIV

1ms/DIV

80A Peak load (resistive) for 50ms
Output voltage dips from 24V to 19V.

200A Peak load (resistive) for 5ms
Output voltage dips from 24V to 17V.

Please note: The DC-OK relay triggers when the voltage dips more than 10% for longer than 1ms.

Peak current voltage dips

typ.
typ.
typ.

from 24V to 19V
from 24V to 18Vfrom 24V to 17V

at 80A for 50ms, resistive load
at 200A for 2ms, resistive load
at 200A for 5ms, resistive load

26.3. EXTERNAL INPUT PROTECTION
The unit is tested and approved for branch circuits up to 30A (U.S.A.) and 32A (IEC). 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 C-Characteristic breaker should be chosen.

Aug. 2024 / Rev. 3.1 DS-QT40.241-EN
All parameters are specified at 24V, 40A, 3x400Vac, +25°C ambient and after a 5 minutes run-in time unless otherwise noted.

25/30
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24V, 40A, THREE PHASE INPUT

Q-Series

26.4. USING ONLY 2 LEGS OF A 3-PHASE SYSTEM
L1
L2
L3
PE

No external protection devices are required to protect against a phase-loss failure.
This power supply can also be permanently operated on two legs of a 3-phase system.
However, it is not recommended for this power class since the supplying 3-phasenetwork can become unbalanced and the lifetime is reduced.

Power Supply

AC
L1
L2

The output power must be reduced according to the curves below when operation on
only two legs of a 3-phase system. A long-term exceeding of these limits will result in athermal shut-down of the unit.

open

L3

DC

A use below 340Vac with more than 30A output current can also result in a thermal shut-down.
During power-on, some start-up attempts can occur until a permanent output power is available.
EMC performance, hold-up time, losses and output ripple differ from a three-phase operation. Therefore, check suitability of yourindividual application.
Such use is not included in the UL approval. Additional tests might be necessary when the complete system has to be approved
according to UL 61010-2-201 .
The screw of the terminal which remains unused must be securely tightened.
Fig. 26-5
Output current vs. ambient temperature

Fig. 26-6
Hold-up time vs. input voltage

Allowed Output Current for Use on only Two
Legs of a 3-Phase System

Hold-up Time for Use on only Two Legs of aThree Phase System

40A
C

30
A... 2x 460 to 552Vac
B... 2x 340 to 460Vac
C... max. 60 seconds

30
24V, 40A, typ.
24V, 40A, min.

20

10
0
-25

24V, 20A, typ.
24V, 20A, min.

40

B A

20

50ms

10
0

20

40

Input Voltage

0320

60 70°C

Ambient Temperature

Fig. 26-7
Efficiency vs. output current at 24V

360

400

Power Losses for Use on only
Two Legs of a 3-Phase System

60W

96%
2x480Vac

2x400Vac50402x400Vac94

3x480Vac

Fig. 26-8
Losses vs. output current at 24V

Efficiency for Use on only
Two Legs of a 3-Phase System

95

440

2x480Vac

30

93

20
Output Current

928Output Current

10

12 16 20 24 28 32 36 40A

04

8 12 16 20 24 28 32 36 40A

Aug. 2024 / Rev. 3.1 DS-QT40.241-EN
All parameters are specified at 24V, 40A, 3x400Vac, +25°C ambient and after a 5 minutes run-in time unless otherwise noted.

26/30
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24V, 40A, THREE PHASE INPUT

Q-Series

26.5. 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 50A or 63A 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. 18mA when the power supply is switched off (except incase a blocking diode is utilized).

26.6. OUTPUT CIRCUIT BREAKERS
Standard miniature circuit breakers (MCB’s or UL1077 circuit breakers) are commonly used for AC-supply systems and may also be usedon DC branches.
MCB’s are designed to protect wires and circuits. If the ampere value and the characteristics of the MCB are adapted to the wire sizethat is used, the wiring is considered as thermally safe regardless of whether the MCB opens or not.
To avoid voltage dips and under-voltage situations in adjacent 24V branches which are supplied by the same source, a fast (magnetic)
tripping of the MCB is desired. A quick shutdown within 10ms is necessary corresponding roughly to the ride-through time of PLC's. Thisrequires power supplies with high current reserves and large output capacitors. Furthermore, the impedance of the faulty branch mustbe sufficiently small in order for the current to actually flow. The best current reserve in the power supply does not help if Ohm’s law
does not permit current flow. The following table has typical test results showing which B- and C-Characteristic MCBs magnetically trip
depending on the wire cross chapter and wire length.
Fig. 26-9 Test circuit

Power Suppl y

DC

MCB

+
Wire l ength

DC S1... Fault simulation switch

*)

Load

+
S1

-

Maximal wire length*) for a fast (magnetic) tripping:
0.75mm²
1.0mm²1.5mm²
C-2A
31 m
42 m
62 m
C-3A
28 m
36 m
51 m
C-4A
18 m
23 m
36 m
C-6A
11 m
14 m
21 m
C-8A
8m
12 m
18 m
C-10A
7m
10 m
15 m
C-13A
4m
6m
8m
C-16A
2m
3m
4m
C-20A
1m
2m
3m
B-6A
23 m
29 m
40 m
B-10A
13 m
16 m
24 m
B-13A
11 m
13 m
20 m
B-16A
8m
12 m
18 m
B-20A
4m
6m
9m
B-25A
3m
4m
7m
B-32A
3m
4m
5m

2.5mm²
92 m
77 m
55 m
33 m
27 m
22 m
13 m
7m
5m
64 m
38 m
32 m
26 m
15 m
9m
7m

Don’t forget to consider twice the distance to the load (or cable length) when calculating the total wire length (+ and – wire).

Aug. 2024 / Rev. 3.1 DS-QT40.241-EN
All parameters are specified at 24V, 40A, 3x400Vac, +25°C ambient and after a 5 minutes run-in time unless otherwise noted.

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24V, 40A, THREE PHASE INPUT

Q-Series

26.7. PARALLEL USE TO INCREASE OUTPUT POWER
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) in “Single use”
mode with the same load conditions on all units, or the units can be left with the factory
settings. After the adjustments, the jumper on the front of the unit shall be moved from“Single use” to “Parallel use”, in order to achieve load sharing. The “Parallel use” mode
regulates the output voltage in such a manner that the voltage at no load is approx. 4%
higher than at nominal load. See also chapter 6. If no jumper is plugged in, the unit is in“Single use” mode. Factory setting is also “Single use” mode.

Unit A

AC

DC

+
+

Unit B

LoadAC

If more than three units are connected in parallel, a fuse or circuit breaker with a ratingof 50A or 63A is required on each output. Alternatively, a diode or redundancy module
can also be utilized.

DC

+
-

-

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 parallel in mounting orientations other than the standard mounting orientation (terminals on thebottom of the unit) or in any other condition where a derating of the output current is required (e.g. altitude, above +60°C, …).
Pay attention that leakage current, EMI, inrush current, harmonics will increase when using multiple power supplies.

26.8. 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 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
40A are paralleled to build a 160A redundant system. For N+1 redundancy the same restrictions apply as for increasing the output
power, see also chapter 26.7.
Please note: This simple way to build a redundant system does not cover failures such as an internal short circuit in the secondary sideof 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 redundancy modules, which have decoupling devices (diodes or MOSFETs)
included. Further information and wiring configurations can be found in chapter 25.3.
Recommendations for building redundant power systems:
a)
b)
c)
d)

Use separate input fuses for each power supply. A separate source for each supply when possible increases the reliability of theredundant system.
Set the power supply into “Parallel Use” mode.
Monitor the individual power supply units. Therefore, use the DC-OK relay contact of the QT40 power supply.
It is desirable to set the output voltages of all units to the same value (± 100mV) or leave it at the factory setting.

Aug. 2024 / Rev. 3.1 DS-QT40.241-EN
All parameters are specified at 24V, 40A, 3x400Vac, +25°C ambient and after a 5 minutes run-in time unless otherwise noted.

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24V, 40A, THREE PHASE INPUT

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26.9. SERIES OPERATIONPower 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.
Earthing of the output is required when the sum of the output voltage is above 60Vdc.

Unit A

AC

DC

+
+

Unit B

Load

AC

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

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 inseries in mounting orientations other than the standard mounting orientation (terminals on the bottom of the unit).

Earth(see notes)

Pay attention that leakage current, EMI, inrush current, harmonics will increase when using multiple power supplies.

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

26.11. 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.

26.12. 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 9522 100, plastic, 254x180x165mm
24V, 32A; (=80%) load is placed outside the box
3x 400Vac+57.5°C (in the middle of the right side of the power supply with a distance of 2cm)
+23.6°C
33.9K

Aug. 2024 / Rev. 3.1 DS-QT40.241-EN
All parameters are specified at 24V, 40A, 3x400Vac, +25°C ambient and after a 5 minutes run-in time unless otherwise noted.

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24V, 40A, THREE PHASE INPUT

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26.13. MOUNTING ORIENTATIONSMounting 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 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. 26-10
Mounting
Orientation A(Standardorientation)

Output Current

40A

A1

30

Power
Supply

20
10

INPUT

Ambient Temperature

0

OUTPU T

10
Fig. 26-11
Mounting
Orientation B(Upside down)

20

30

40

50

60°C

Output Current

40A
30

A2

20

A1

INPUT

OUTPU T

Power
Supply10
Ambient Temperature

010Fig. 26-12
Mounting
Orientation C(Table-top
mounting)

20

30

40

50

60°C

Output Current

40A
30

A2
A1

20
10

Ambient Temperature

0
10

40

50

60°C

40A

OUTPU T

Power
Supply

30

A2
A1

20
10
Ambient Temperature

0
10

20

30

40

50

60°C

Output Current
OUTPU T

30

INPUT

40A

Power
SupplyFig. 26-14
Mounting
Orientation E(Horizontal ccw)

30

Output Current
INPUT

Fig. 26-13
Mounting
Orientation D(Horizontal cw)

20

10

A2
A1

20
Ambient Temperature

0
10

20

30

40

50

60°C

Aug. 2024 / Rev. 3.1 DS-QT40.241-EN
All parameters are specified at 24V, 40A, 3x400Vac, +25°C ambient and after a 5 minutes run-in time unless otherwise noted.

30/30
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