CPS20.241, CPS20.241-C1
24V, 20A, SINGLE PHASE INPUT

C-Series

POWER SUPPLY
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AC 100-240V Wide-range Input
Width only 65mm
Efficiency up to 94.0%
ATEX and IECEx Approved-C1 Version with Conformal Coated PC-Board
Excellent Partial Load Efficiency
20% Output Power Reserves
Safe HiccupPLUS Overload Mode
Easy Fuse Breaking due to High Overload Current
Active Power Factor Correction (PFC)
Minimal Inrush Current Surge
Full Power Between -25°C and +60°C
DC-OK Relay Contact
Current Sharing Feature for Parallel Use
3 Year Warranty

GENERAL DESCRIPTIONSHORT-FORM DATAThe Dimension C-Series are cost optimized power
supplies without compromising quality, reliability andperformance. The C-Series is part of the DIMENSION
power supply family. The most outstanding features of
CPS20.241 are the high efficiency, electronic inrush
current limitation, active PFC, wide operationaltemperature range. The small size is achieved by asynchronous rectification and further technologicaldesign details.

Output voltage
Adjustment range
Output current

The C-Series includes all the essential basic functions.
The devices have a power reserve of 20% included,
which may even be used continuously at temperatures
up to +45°C. Additionally, the CPS20.241 can deliver
about 4 times the nominal output current for 15ms
which helps to trip fuses on faulty output branches.
High immunity to transients and power surges as well as
low electromagnetic emission, a DC-OK relay contact
and a large international approval package for a variety
of applications makes this unit suitable for nearly every
situation.

DC 24V24 - 28V
20A
at 24V, amb <60°C
24A
at 24V, amb <45°C
17.1A
at 28V, amb <60°C
20.6A
at 28V, amb <45°C
Output power
480W
ambient <60°C
576W
ambient <45°C
Output ripple< 50mVpp
20Hz to 20MHz
AC Input voltage
AC 100-240V-15%/+10%
Mains frequency
50-60Hz±6%
AC Input current
4.36 / 2.33A
at 120 / 230Vac
Power factor
0.99 / 0.95
at 120 / 230Vac
AC Inrush current
typ. 9 / 7A peak at 120 / 230Vac
Efficiency
92.7 / 94.0%
at 120 / 230Vac
Losses37.8 / 30.6W
at 120 / 230Vac
Temperature range -25°C to +70°C operational
Derating *)12W/°C+60 to +70°C
Hold-up time
typ. 26 / 26ms
at 120 / 230Vac
Dimensions
65x124x127mm WxHxD
Weight1000g / 2.2lb*) between 100-85Vac see chapter 15

ORDER NUMBERS

MARKINGSPower Supply

CPS20.241
24-28V Standard unit
CPS20.241-C1 Conformal coated unit

Accessory

ZM2.WALL
ZM13.SIDE
YR40.242
YR40.245

Wall mount bracket
Side mount bracket
Redundancy module
Redundancy module

IND. CONT. EQ.
UL 508

UL 60950-1

IECEx
Class I Div 2

ATEX

II 3G Ex nA nC II T3 Gc

Apr. 2014 / Rev. 1.6 DS-CPS20.241-EN
All parameters are specified at 24V, 20A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0Germany

Marine

EMC, LVD, RoHS

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CPS20.241, CPS20.241-C1
24V, 20A, SINGLE PHASE INPUT

C-Series

INDEX
Page
1. Intended Use .......................................................3
2. Installation Requirements...................................3
3. AC-Input...............................................................4
4. DC-Input...............................................................5
5. Input Inrush Current ...........................................5
6. Output .................................................................6
7. Hold-up Time.......................................................8
8. DC-OK Relay Contact ..........................................8
9. Efficiency and Power Losses................................910. Lifetime Expectancy and MTBF.........................10
11. Functional Diagram...........................................10
12. Terminals and Wiring........................................11
13. Front Side and User Elements...........................12
14. EMC....................................................................13
15. Environment ......................................................14
16. Protection Features ...........................................15
17. Safety Features ..................................................15
18. Dielectric Strength ............................................16
19. Approvals...........................................................17Page
20. Physical Dimensions and Weight ..................... 18
21. Accessories ........................................................ 19
21.1. ZM2.WALL - Wall Mounting Bracket.......19
21.2. ZM13.SIDE - Side Mounting Bracket........19
21.3. Redundancy Modules ...............................20
22. Application Notes............................................. 21
22.1. Peak Current Capability ...........................2122.2. Back-feeding Loads ..................................22
22.3. External Input Protection.........................2222.4. Output Circuit Breakers............................22
22.5. Parallel Use to Increase Output Power....23
22.6. Parallel Use for Redundancy ....................23
22.7. Series Operation .......................................24
22.8. Inductive and Capacitive Loads................24
22.9. Charging of Batteries ...............................24
22.10. Operation on Two Phases ........................25
22.11. Use in a Tightly Sealed Enclosure ............25
22.12. Mounting Orientations ............................26

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 230V

A figure displayed with the AC or DC before the value represents a nominal voltage withstandard 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.

Apr. 2014 / Rev. 1.6 DS-CPS20.241-EN
All parameters are specified at 24V, 20A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0Germany

2/26

CPS20.241, CPS20.241-C1
24V, 20A, SINGLE PHASE INPUT

C-Series

1. INTENDED USEThis device is designed for installation in an enclosure and is intended for the general professional use such as inindustrial control, office, communication, and instrumentation equipment.
Do not use this power supply in equipment, where malfunction may cause severe personal injury or threaten humanlife.
This device is designed for use in hazardous, non-hazardous, ordinary or unclassified locations.

2. INSTALLATION REQUIREMENTS
This device may only be installed and put into operation by qualified personnel.
This device does not contain serviceable parts. The tripping of an internal fuse is caused by an internal defect.
If damage or malfunction should occur during installation or operation, immediately turn power off and send unit to
the factory for inspection.
Mount the unit on a DIN-rail so that the terminals are located on the bottom of the unit. For other mounting
orientations see de-rating requirements in this document. See chapter 24.13.
This device is designed for convection cooling and does not require an external fan. Do not obstruct airflow and do
not cover ventilation grid (e.g. cable conduits) by more than 15%!
Keep the following installation clearances: 40mm on top, 20mm on the bottom, 5mm on the left and right sides arerecommended when the device is loaded permanently with more than 50% of the rated power. Increase this clearance
to 15mm in case the adjacent device is a heat source (e.g. another power supply).
A disconnecting means shall be provided for the output of the power supplies when used in applications according to
CSA C22.2 No 107.1-01.

WARNING

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

- Do not use the power supply without proper grounding (Protective Earth). Use the terminal on the input block forearth connection and not one of the screws on the housing.
- Turn power off before working on the device. Protect against inadvertent re-powering.
- Make sure that the wiring is correct by following all local and national codes.
- Do not modify or repair the unit.
- Do not open the unit as high voltages are present inside.
- Use caution to prevent any foreign objects from entering the housing.
- Do not use in wet locations or in areas where moisture or condensation can be expected.
- Do not touch during power-on, and immediately after power-off. Hot surfaces may cause burns.

Notes for use in hazardous location areas:
The power supply is suitable for use in Class I Division 2 Groups A, B, C, D locations and for use in Group II Category 3(Zone 2) environments and are evaluated according to EN 60079-0:2012 and EN 60079-15:2010.
WARNING EXPLOSION HAZARDS!
Substitution of components may impair suitability for this environment. Do not disconnect the unit or operate thevoltage adjustment or S/P jumper unless power has been switched off or the area is known to be non-hazardous.
A suitable enclosure must be provided for the end product which has a minimum protection of IP54 and fulfils therequirements of the EN 60079-15:2010.

Apr. 2014 / Rev. 1.6 DS-CPS20.241-EN
All parameters are specified at 24V, 20A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0Germany

3/26

CPS20.241, CPS20.241-C1
24V, 20A, SINGLE PHASE INPUT

C-Series

3. AC-INPUT
AC input
AC input range

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

nom.
min.
min.

AC 100-240V
100-264Vac
85-100Vac

suitable for TN-, TT- and IT mains networks
continuous operation
short term or with output derating (1%/V) or with
reduced ambient temperature, see Fig. 15-1,
no damage between 0 and 100Vac< 500ms
continuous, IEC 62103±6%
steady-state value, see Fig. 3-1
steady-state value at 5A load, see Fig. 3-1
steady-state value at 10A load, see Fig. 3-1
steady-state value at 20A load, see Fig. 3-1

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

264-300Vac
300Vac50–60Hz
84Vac
39Vac
53Vac
74Vac

typ.
typ.
typ.
typ.
typ.

AC 100V
5.25A
0.99
1.5
850ms
85ms

AC 120V
4.36A
0.99
1.5
850ms
85ms

AC 230V
2.33A
0.95
1.65
650ms
85ms

typ.

150ms

150ms

150ms

max.

200mV

200mV

200mV

at 24V, 20A, see Fig. 3-3
at 24V, 20A, see Fig. 3-4
at 24V, 20A
see Fig. 3-2
at 24V, 20A const. current load,
0mF load capacitance, see Fig. 3-2
at 24V, 20A const. current load,
20mF load capacitance,, 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-down

Input
Voltage

max.
500ms

VIN
85V

Start-up
delay

Input Current, typ.

Rise
Time

264V 300Vac

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

6A

- 5%

OutputVoltage

Overshoot

Rated
input range

POUT

Fig. 3-2 Turn-on behavior, definitionsaFig. 3-4 Power factor vs. output load
Power Factor, typ.
a, b

1.0

b

5
4
3

c

0.95

a) 100Vacb) 120Vacc) 230Vac

0.9ca) 100Vacb) 120Vacc) 230Vac

0.85

2

0.8

1
Output Current

0

Output Current

0.75

2

4

6

8 10 12 14 16 18 20 22 24A

2

4

6

8 10 12 14 16 18 20 22 24A

Apr. 2014 / Rev. 1.6 DS-CPS20.241-EN
All parameters are specified at 24V, 20A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0Germany

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CPS20.241, CPS20.241-C1
24V, 20A, SINGLE PHASE INPUT

C-Series

4. DC-INPUT
Do not operate this power supply with DC-input voltage. Use the CPS20.241-D1 unit instead.

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

max.
typ.
max.
typ.

Inrush energy*)
Inrush delay*)

AC 100V
13Apeak
11Apeak
2A2s
935ms

AC 120V
13Apeak
9Apeak
2.5A2s935ms

AC 230V
13Apeak
7Apeak
0.5A2s735ms

temperature independent
temperature independent
temperature independent
start-up delay plus rise time

Mains interruptions > 500ms

Fig. 5-1 Typical input inrush current
behaviour at nominal load and 25°C ambient
Input Current 5A / DIV

Input

230Vac24Vdc
Output

100mS/DIV

Apr. 2014 / Rev. 1.6 DS-CPS20.241-EN
All parameters are specified at 24V, 20A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0Germany

5/26

CPS20.241, CPS20.241-C1
24V, 20A, SINGLE PHASE INPUT

C-Series

6. OUTPUT
Output voltage
Adjustment range

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

24V
24-28V
30V****)
24.1V
24.1V
25.1V
10mV
100mV

typ.

1000mV

Ripple and noise voltage
Output current

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

50mVpp
20A
24A*)
17.1A
20.6A*)
80A

Output power

nom.
nom.

min.
max.
max.

480W
576W*)
cont. current
HiccupPLUS mode**)35A***)
45A***)
15A***)

min.
typ.
typ.

70A
100A
7 000μF

Factory settings

Line regulation
Load regulation

Overload behaviour
Short-circuit current

Output capacitance
*)

**)

***)
****)

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
85-300Vac
in “single use” mode: static value, 0A Æ 20A;
see Fig. 6-1
in “parallel use” mode: static value, 0A Æ 20A,
see Fig. 6-2
20Hz to 20MHz, 50Ohm
at 24V, ambient temperature <60°C, see Fig. 6-1
at 24V, ambient temperature <45°C, see Fig. 6-1
at 28V, ambient temperature <60°C, see Fig. 6-1
at 28V, ambient temperature <45°C, see Fig. 6-1
up to 15ms, output voltage stays above 20V, see Fig.
6-4, This peak current is available once every fiveseconds. See chapter 22.1 for more peak current
measurements.
continuously available
Power Boost® *)output voltage > 13Vdc, see Fig. 6-1
output voltage < 13Vdc, see Fig. 6-1
load impedance <10mOhm, see Fig. 6-3
load impedance <10mOhm, see Fig. 6-3
average (R.M.S.) current, load impedance 50mOhm,
see Fig. 6-3
up to 15ms, load impedance <10mOhm, see Fig. 6-4
up to 15ms, load impedance <10mOhm, see Fig. 6-4
included inside the power supply

Power Boost
This power/ current is continuously allowed up to an ambient temperature of 45°C.
Above 45°C, do not use this power/ current longer than a duty cycle of 10% and/ or not longer than 1 minute every 10 minutes.
HiccupPLUS ModeAt heavy overloads (when output voltage falls below 13V), the power supply delivers continuous output current for 2s. After this, theoutput is switched off for approx. 18s before a new start attempt is automatically performed. This cycle is repeated as long as theoverload exists. If the overload has been cleared, the device will operate normally. See Fig. 6-3
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 notguaranteed value which can be achieved. The typical value is about 28.5V (in “single use” mode).

Apr. 2014 / Rev. 1.6 DS-CPS20.241-EN
All parameters are specified at 24V, 20A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0Germany

6/26

CPS20.241, CPS20.241-C1
24V, 20A, SINGLE PHASE INPUT

C-Series

Fig. 6-2 Output voltage in “parallel use”
mode, typ.

Fig. 6-1 Output voltage vs. output current,
typ.
Output Voltage (Single Use, typ.)

28V
Factory
setting16

Adjustment
Range

29V

Continuous
current

24
20

Output Voltage (Parallel Use, typ.)Adjustment
Range

28V
27V
26V
25V

12
8
4
0

23V
22V

Output Current

0

5

10

15

20

25

30

Factory
setting

24V

Hiccupmode

35 40A

Output Current

40

Fig. 6-3 Short-circuit on output, HiccupPLUS mode, typ.

8

12

16

20

24A

Fig. 6-4 Dynamic overcurrent capability, typ.
Output Voltage (dynamic behavior, < 15ms)

28V

OutputCurrent
Normaloperation

Normaloperation

Short -circuit

42A

24
20

Adjustment
Range

16
12
t

0
2s

18s

2s

18s

2s

18s

8
4
0

Output Current

0 10 20 30 40 50 60 70 80 90 100A

Apr. 2014 / Rev. 1.6 DS-CPS20.241-EN
All parameters are specified at 24V, 20A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0Germany

7/26

CPS20.241, CPS20.241-C1
24V, 20A, SINGLE PHASE INPUT

C-Series

7. HOLD-UP TIME
Hold-up TimeAC 100V
65ms
54ms
26ms
21ms

typ.
min.
typ.
min.

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

AC 120V
65ms
54ms
26ms
21ms

AC 230V
65ms
54ms
26ms
21ms

at 24V, 10A, see Fig. 7-1
at 24V, 10A, see Fig. 7-1
at 24V, 20A, see Fig. 7-1
at 24V, 20A, see Fig. 7-1

Fig. 7-2 Shut-down behavior, definitions

Hold-up Time

Zero Transition

80ms
70
60
50
40
30
20
10
0

24V, 10A, typ.
24V, 10A, min.

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

Input
Voltage

Hold-up Time

Input Voltage

90

120

155

190

- 5%

OutputVoltage

230Vac8. 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 a unit 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 level.
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 100ms. Dips shorter than 1ms will be ignored.
max.
60Vdc 0.3A, 30Vdc 1A, 30Vac 0.5A
resistive loadmin.
1mA at 5Vdc
min. permissible load
See dielectric strength table in section 18.

Contact ratings
Isolation voltage

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

<
1ms

open

closed>1ms

0.9* VADJ

100ms

open

closedApr. 2014 / Rev. 1.6 DS-CPS20.241-EN
All parameters are specified at 24V, 20A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0Germany

8/26

CPS20.241, CPS20.241-C1
24V, 20A, SINGLE PHASE INPUT

C-Series

9. EFFICIENCY AND POWER LOSSES
Efficiency
Average efficiency*)
Power losses

*)

typ.
typ.
typ.

AC 100V
92.0%
91.6%
91.3%

AC 120V
92.7%
92.4%
92.0%

AC 230V
94.0%
94.0%
93.3%

typ.
typ.
typ.
typ.

6.5W
21.1W
41.7W
52.8W

3.9W
20.1W
37.8W
47.4W

2.6W
17.0W
30.6W
36.8W

at 24V, 20A
at 24V, 24A (Power Boost)
25% at 5A, 25% at 10A,
25% at 15A. 25% at 20A
at 24V, 0A
at 24V, 10A
at 24V, 20A
at 24V, 24A (Power Boost)

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 the time.

Fig. 9-1 Efficiency vs. output current at 24V,
typFig. 9-2 Losses vs. output current at 24V, typ.

Efficiency

Power Losses
230Vac

94%
93
92
91
90
89
88
87
86

120Vac100Vac

60W
100Vac50

120Vac4030
230Vac20
10Output Current

46Output Current

0

8 10 12 14 16 18 20 22 24A

0 2 4 6 8 10 12 14 16 18 20 22 24A

Fig. 9-3 Efficiency vs. input voltage at 24V,
20A, typ.

Fig. 9-4 Losses vs. input voltage at 24V, 20A,
typ.

Efficiency

Power Losses

95%

50W

94

45

93

40

92

35

91

30

90

25
Input Voltage

89
100 120

180

Input Voltage

20230

264Vac100 120180

230

264VacApr. 2014 / Rev. 1.6 DS-CPS20.241-EN
All parameters are specified at 24V, 20A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0Germany

9/26

CPS20.241, CPS20.241-C1
24V, 20A, SINGLE PHASE INPUT

C-Series

10. LIFETIME EXPECTANCY AND MTBF
Lifetime expectancy*)

MTBF**) SN 29500, IEC 61709
MTBF**) MIL HDBK 217F

AC 100V
145 000h*)
410 000h*)
64 000h
180 000h*)
38 000h
109 000h*)
468 000h
770 000h
254 000h

AC 120V
150 000h*)
425 000h*)
70 000h
198 000h*)
46 000h
130 000h*)
484 000h
796 000h
261 000h

AC 230V
168 000h*)
475 000h*)
88 000h
249 000h*)
61 000h
171 000h*)
537 000h
882 000h
290 000h

355 000h

361 000h

395 000h

56 000h

57 000h64 000h75 000h77 000h86 000hat 24V, 10A and 40°C
at 24V, 10A and 25°C
at 24V, 20A and 40°C
at 24V, 20A and 25°C
at 24V, 24A and 40°C
at 24V, 24A and 25°C
at 24V, 20A and 40°C
at 24V, 20A and 25°C
at 24V, 20A and 40°C;
Ground Benign GB40
at 24V, 20A and 25°C;
Ground Benign GB25
at 24V, 20A and 40°C;
Ground Fixed GF40
at 24V, 20A and 25°C;
Ground Fixed GF25*)

The Lifetime expectancy shown in the table indicates the minimum operating hours (service life) and is determined by the lifetime
expectancy of the built-in electrolytic capacitors. Lifetime expectancy is specified in operational hours and is calculated according to thecapacitor’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 adevice. It is the statistical representation of the likelihood of a unit to fail and does not necessarily represent the life of a product.
The MTBF figure is a statistical representation of the likelihood of a device to fail. A MTBF figure of e.g. 1 000 000h means thatstatistically one unit will fail every 100 hours if 10 000 units are installed in the field. However, it can not be determined if the failed unit
has been running for 50 000h or only for 100h.

11. FUNCTIONAL DIAGRAM
Fig. 11-1 Functional diagram

L
N

Input Fuse
Input Filter
Input Rectifier
Active Inrush Limiter

PFC
ConverterPower
Converter

OutputFilterOutputVoltage
Regulator
Temperature
Shutdown

OutputPower
Manager

OutputOverVoltage
Protection

OutputVoltage
Monitor++Single /Parallel

VOUT
DC-ok
LED

DC-ok
Relay

DC-ok
Contact

Apr. 2014 / Rev. 1.6 DS-CPS20.241-EN
All parameters are specified at 24V, 20A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0Germany

10/26

CPS20.241, CPS20.241-C1
24V, 20A, SINGLE PHASE INPUT

C-Series

12. TERMINALS AND WIRING
The terminals are IP20 Finger safe constructed and suitable for field- and factory wiring.
Input and output
screw terminals
0.5-6mm2
0.5-4mm2
AWG20-10
2.8mm (including ferrules)
7mm / 0.28inch
3.5mm slotted or cross-head No 2
1Nm, 9lb.in

Type
Solid wire
Stranded wire
American Wire Gauge
Max. wire diameter
Wire stripping length
Screwdriver
Recommended tightening torque

DC-OK-Signal
spring-clamp terminals
0.15-1.5mm2
0.15-1.5mm2
AWG26-14
1.5mm (including ferrules)
7mm / 0.28inch
3.5mm 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 25A. If the current is higher, use a separate distribution terminal block asshown in Fig. 12-2.
Fig. 12-1 Daisy chaining of outputs

Power
Supply+ + Output-

Fig. 12-2 Using distribution terminals

Distribution
Terminals

Power
Supply+ + --Output

Load
+

-

Power
SupplyPower
Supply

+ + -

+ + -

-

Output-OutputLoad+-max 25A!
continuous

Apr. 2014 / Rev. 1.6 DS-CPS20.241-EN
All parameters are specified at 24V, 20A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0Germany

11/26

CPS20.241, CPS20.241-C1
24V, 20A, SINGLE PHASE INPUT

C-Series

13. FRONT SIDE AND USER ELEMENTS
Fig. 13-1 Front sideA

Input Terminals (screw terminals)
N, LLine input
PE (Protective Earth) input

B

Output Terminals (screw terminals, two pins per pole)+
Positive output–
Negative (return) output

C

Output voltage 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

DC-OK Relay Contact (quick-connect spring-clamp terminals)
The DC-OK relay contact is synchronized with the DC-OK LED.
See chapter 8 for details.

F“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 22.5. A missing jumper isequal to a “Single Use” mode.

Apr. 2014 / Rev. 1.6 DS-CPS20.241-EN
All parameters are specified at 24V, 20A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0Germany

12/26

CPS20.241, CPS20.241-C1
24V, 20A, SINGLE PHASE INPUT

C-Series

14. EMCThe power supply is suitable for applications in industrial environment as well as in residential, commercial and lightindustry environment without any restrictions. A detailed EMC report is available on request.
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

Voltage interruptions
Voltage sags

Powerful transients

According generic standards: EN 61000-6-1 and EN 61000-6-2
EN 61000-4-2
contact discharge
8kV
Criterion A
air discharge
15kV
Criterion A
EN 61000-4-3
80MHz-2.7GHz
20V/m
Criterion A
EN 61000-4-4
input lines
4kV
Criterion A
output lines
2kV
Criterion A
DC-OK signal (coupling clamp)
2kV
Criterion A
EN 61000-4-5LÆN
2kV
Criterion A
L Æ PE, N Æ PE
4kV
Criterion A
EN 61000-4-5+Æ1kV
Criterion A+ / - Æ PE
2kV
Criterion A
EN 61000-4-5
DC-OK signal Æ PE
1kV
Criterion A
EN 61000-4-6
0.15-80MHz
20V
Criterion A
EN 61000-4-11
0% of 100Vac
0Vac, 20ms
Criterion A
40% of 100Vac
40Vac, 200ms
Criterion C
70% of 100Vac
70Vac, 500ms
Criterion A
0% of 200Vac
0Vac, 20ms
Criterion A
40% of 200Vac
80Vac, 200ms
Criterion A
70% of 200Vac
140Vac, 500ms
Criterion A
EN 61000-4-11
0% of 200Vac (=0V)
5000msCriterion C
SEMI F47 0706
dips on the input voltage according to SEMI F47 standard
1000msCriterion A
80% of 120Vac (96Vac)
500ms
Criterion A
70% of 120Vac (84Vac)
50% of 120Vac (60Vac)
200ms
Criterion A
VDE 0160
over entire load range
750V, 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.

According generic standards: EN 61000-6-3 and EN 61000-6-4
EMC Emission
Conducted emission
EN 55011, EN 55022, FCC Part 15, CISPR 11, CISPR 22
Class B
input lines
IEC/CISPR 16-1-2, IEC/CISPR 16-2-1
limits for DC power port
Conducted emission
according EN 61000-6-3 fulfilled
output lines**)Radiated emission
EN 55011, EN 55022
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) thisdevice 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

Apr. 2014 / Rev. 1.6 DS-CPS20.241-EN
All parameters are specified at 24V, 20A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0Germany

13/26

CPS20.241, CPS20.241-C1
24V, 20A, SINGLE PHASE INPUT

C-Series

The power supply has two converters with two different switching frequencies included.
70kHz to 130kHz
PFC converter, input voltage and output power dependent
80kHz to 140kHz
Main converter, output power dependent

Switching Frequencies
Switching frequency 1
Switching frequency 2

15. ENVIRONMENT
Operational temperature*)
Storage temperature
Output de-rating-25°C to +70°C (-13°F to 158°F)-40°C to +85°C (-40°F to 185°F)
6.4W/°C
12W/°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 (0 to 6 560ft)
2000 to 6000m (6 560 to 20 000ft)

Humidity**)Vibration sinusoidal
Shock
Altitudereduce output power according Fig. 15-1
for storage and transportation
45°C to 60°C (113°F to 140°F)
60°C to 70°C (140°F to 158°F)
IEC 60068-2-30
IEC 60068-2-6
IEC 60068-2-27

without any restrictions
reduce output power or ambient temperature,
see Fig. 15-2
IEC 62103, EN 50178, overvoltage category II
30W/1000m or 5°C/1000m> 2000m (6500ft), see Fig. 15-2
III
IEC 62103, EN 50178, altitudes up to 2000m
II
altitudes from 2000m to 6000m
2
IEC 62103, EN 50178, not conductive
The unit does not release any silicone or other LABS-critical substances and is suitable foruse in paint shops.
At load currents below 2A some audible noise will be emitted from the power supply

Altitude de-rating
Over-voltage category
Degree of pollution
LABS compatibility
Audible noise*)

Operational temperature is the same as the ambient or surrounding temperature and is defined as the air temperature 2cm below theunit.
**) Do not energize while condensation is present***) Tested in combination with DIN-Rails according to EN 60715 with a height of 15mm and a thickness of 1.3mm and standard
orientation. Higher levels allowed when using the wall mounting bracket ZM2.WALL

Fig. 15-1 Output current vs. ambient temp.
Allowed Output Current at 24V

24A

C
A

20A

24A

16A

12A

4A
0
-25

D
C
B
A

20A

B

16A

8A

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

12A
A...100 to 264Vac, continuous
B... 85Vac, continuous
C... short term

0

20

40

A... Tamb < 60°C
B... Tamb < 50°C
C... Tamb < 40°C
D... Short term

8A
4A
60 70°C

0
0

2000m

Ambient Temperature

4000m

6000m
AltitudeSee chapter 3 for de-rating requirements for input voltages between 85Vac and 100Vac.

Apr. 2014 / Rev. 1.6 DS-CPS20.241-EN
All parameters are specified at 24V, 20A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0Germany

14/26

CPS20.241, CPS20.241-C1
24V, 20A, SINGLE PHASE INPUT

C-Series

16. PROTECTION FEATURES
Output protection
Output over-voltage protection

Degree of protection

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

Electronically protected against overload, no-load and short-circuits*)
typ. 30.5Vdc
In case of an internal power supply defect, a redundantmax. 32Vdc
circuit limits the maximum output voltage. The output
shuts down and automatically attempts to restart.
IP 20
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.

17. SAFETY FEATURES
Input / output separation*)

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

*)

SELV
IEC/EN 60950-1
PELV
IEC/EN 60204-1, EN 50178, IEC 62103, IEC 60364-4-41
double or reinforced insulation
I
PE (Protective Earth) connection required> 5MOhm
input to output, 500Vdc< 0.1Ohm
typ. 0.14mA / 0.37mA
100Vac, 50Hz, TN-,TT-mains / IT-mains
typ. 0.20mA / 0.55mA
120Vac, 60Hz, TN-,TT-mains / IT-mains
typ. 0.35mA / 0.87mA
230Vac, 50Hz, TN-,TT-mains / IT-mains
max. 0.17mA / 0.46mA
110Vac, 50Hz, TN-,TT-mains / IT-mains
max. 0.26mA / 0.67mA
132Vac, 60Hz, TN-,TT-mains / IT-mains
max. 0.46mA / 1.08mA
264Vac, 50Hz, TN-,TT-mains / IT-mains

double or reinforced insulation

Apr. 2014 / Rev. 1.6 DS-CPS20.241-EN
All parameters are specified at 24V, 20A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0Germany

15/26

CPS20.241, CPS20.241-C1
24V, 20A, SINGLE PHASE INPUT

C-Series

18. DIELECTRIC STRENGTH
The output voltage is floating and has no ohmic connection to the ground. Type and factory tests are conducted by
the manufacturer. Field tests may be conducted in the field using the appropriate test equipment which applies thevoltage with a slow ramp (2s up and 2s down). Connect all input-terminals together as well as all output poles before
conducting the test. When testing, set the cut-off current settings to the value in the table below.
Fig. 18-1 Dielectric strength

Type test
Input

DC-ok
B *)

L
N

60s

B

D
OutputEarth, PE
C

+

-

B
3000Vac

C
1000Vac

D
500VacFactory test

5s

2500Vac

2500Vac

500Vac

500VacField test

5s

2000Vac

2000Vac

500Vac

500Vac> 15mA> 15mA> 20mA> 1mA

Cut-off current setting
A

A
2500Vac

To fulfil the PELV requirements according to EN60204-1 § 6.4.1, werecommend that either the + pole, the – pole or any other part ofthe output circuit shall be connected to the protective earthsystem. 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.

Apr. 2014 / Rev. 1.6 DS-CPS20.241-EN
All parameters are specified at 24V, 20A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0Germany

16/26

CPS20.241, CPS20.241-C1
24V, 20A, SINGLE PHASE INPUT

C-Series

19. APPROVALSEC Declaration of Conformity

The CE mark indicates conformance with the- EMC directive 2004/108/EC,- Low-voltage directive (LVD) 2006/95/EC,- RoHS directive 2011/65/EU and the- ATEX directive 94/9/EC (for use in explosive atmospheres)
CB Scheme,
Information Technology Equipment

IEC 60950-1
2nd Edition
UL 508IND. CONT. EQ.

UL 60950-1
2nd Edition

ANSI / ISA 12.12.01-2007
Class I Div 2
EN 60079-0, EN 60079-15
ATEX
II 3G Ex nA nC II T3 Gc

IEC 60079-0, IEC 60079-15
MarineGOST R

IECEx

Listed for use as Industrial Control Equipment;
U.S.A. (UL 508) and Canada (C22.2 No. 107-1-01);
E-File: E198865
Recognized for use as Information Technology Equipment,
Level 5; U.S.A. (UL 60950-1) and Canada (C22.2 No. 60950-1);
E-File: E137006
Applicable for altitudes up to 2000m.
Recognized for use in Hazardous Location Class I Div 2 T3Groups A,B,C,D systems; U.S.A. (ANSI / ISA 12.12.01-2007) andCanada (C22.2 No. 213-M1987)
Approval for use in hazardous locations Zone 2 Category 3G.
Number of ATEX certificate: EPS 13 ATEX 1 555 X
The power supply must be built-in in an IP54 enclosure.
Suitable for use in Class 1 Zone 2 Groups IIa, IIb and IIc
locations. Number of IECEx certificate: IECEx EPS 13.0016X
GL (Germanischer Lloyd) classified
Environmental category: C, EMC2Marine and offshore applications
Certificate of Conformity for Russia and other GUS countries

Apr. 2014 / Rev. 1.6 DS-CPS20.241-EN
All parameters are specified at 24V, 20A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0Germany

17/26

CPS20.241, CPS20.241-C1
24V, 20A, SINGLE PHASE INPUT

C-Series

20. PHYSICAL DIMENSIONS AND WEIGHT
WeightDIN-Rail

Installation Clearances

1000g / 2.2lb
Use 35mm DIN-rails according to EN 60715 or EN 50022 with a height of 7.5 or 15mm.
The DIN-rail height must be added to the unit depth (127mm) to calculate the total required
installation depth.
See chapter 2

Fig. 20-1 Front viewFig. 20-2 Side viewApr. 2014 / Rev. 1.6 DS-CPS20.241-EN
All parameters are specified at 24V, 20A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0Germany

18/26

CPS20.241, CPS20.241-C1
24V, 20A, SINGLE PHASE INPUT

C-Series

21. ACCESSORIES

21.1. ZM2.WALL - WALL MOUNTING BRACKETThis bracket is used to mount the power
supply onto a flat surface without utilizing a DIN-Rail.

21.2. ZM13.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

Apr. 2014 / Rev. 1.6 DS-CPS20.241-EN
All parameters are specified at 24V, 20A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0Germany

19/26

CPS20.241, CPS20.241-C1
24V, 20A, SINGLE PHASE INPUT

C-Series

21.3. REDUNDANCY MODULES
YR40.242 – (2x 20A Inputs, 1x 40A output)
The YR40.242 is equipped with two input channels, which are individually decoupled byutilizing mosfet technology. Using mosfets instead of diodes reduces the heat generation andthe voltage drop between input and output. The YR40.242 does not require an additional
auxiliary voltage and is self-powered even in case of a short circuit across the output.
Due to the low power losses, the unit is very slender and only requires 36mm width on the
DIN-rail.

YR40.245 – (1x 40A input, 1x 40A output)
The YR40.245 is a 40A single channel redundancy module, which is equipped with a plugconnector on the output. The plug connector allows replacing the power supply or the
redundancy module while the system is running. The plug connector avoids that the output
wires can touch and short the load circuit.
The YR40.245 is very slender and only requires 46mm width on the DIN-rail. It also utilizes
mosfet technology instead of diodes for low heat generation and a minimal voltage drop
between input and output. It does not require an additional auxiliary voltage and is selfpowered even in case of a short circuit across the output.

Fig. 21-2 Typical N+1 or 1+1 Redundant configuration for 20A withmultiple YR40.245 redundancy modules

Fig. 21-1 Typical 1+1 Redundant configurationfor 20A with a dual redundancy module
24V
20A
Load

CPS20.241
24-28V 480W
Power
Supply+AC Input

I

L
N
PE

Output24V 20A+ +CPS20.241
24-28V 480W
Power
SupplyCPS20.241
24-28V 480W
Power
SupplyDCOK

DCOK

YR40.242*)
Redundancy
ModuleDCOK

L N PE-

Output- -Input Input
1
2

AC Input+ - + -

L N PE

I

24V
20A
Load

FailureMonitorFailureMonitor

Output24V 20A+ +AC Input- -L N PE*) YR40.241

also possible

OutputYR40.245
Redundancy
ModuleOutput24V 20A+ +CPS20.241
24-28V 480W
Power
Supply

-

+

- -

I

OutputYR40.245
Redundancy
Module

DCOK

Input

+

AC Input-

L N PE

Output24V 20A

+ +

-

+

- -

Input

+

-

I

L
N
PE

Apr. 2014 / Rev. 1.6 DS-CPS20.241-EN
All parameters are specified at 24V, 20A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0Germany

20/26

CPS20.241, CPS20.241-C1
24V, 20A, SINGLE PHASE INPUT

C-Series

22. APPLICATION NOTES
22.1. PEAK CURRENT CAPABILITY
The unit 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 PowerBoost). The same situation applies whenstarting a capacitive load.
The peak current capability also ensures the safe operation of subsequent circuit breakers of load circuits. The loadbranches are often individually protected with circuit breakers or fuses. In case of a short or an overload in one branch
circuit, the fuse or circuit breaker need a certain amount of over-current to open in a timely manner. This avoids
voltage loss in adjacent circuits.
The extra current (peak current) is supplied by the 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 typical voltage dips:
Fig. 22-2 Peak load with 5x the nominal
current for 5ms, typ.

Fig. 22-1 Peak load with 2x the nominal
current for 50ms, typ.
15ms

24V

OutputVoltage

24V

OutputVoltage
18V

100A

16V
40A

OutputCurrent

OutputCurrent

0A

0A

10ms/DIV

40A Peak load (resistive) for 50ms
Output voltage dips from 24V to 16V.

1ms/DIV

100A Peak load (resistive) for 5ms
Output voltage dips from 24V to 18V.

Fig. 22-3 90A Peak load, typ.

90A peakOutput Current

24V

Output Voltage
18V

15ms
0A

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

10ms/DIVHigh Overload Current (typ. >90A for15ms) enables easy fuse tripping
Peak current voltage dips

typ.
typ.
typ.

from 24V to 16Vfrom 24V to 18.5V
from 24V to 18V

at 40A for 50ms, resistive load
at 100A for 2ms, resistive load
at 100A for 5ms, resistive load

Apr. 2014 / Rev. 1.6 DS-CPS20.241-EN
All parameters are specified at 24V, 20A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0Germany

21/26

CPS20.241, CPS20.241-C1
24V, 20A, SINGLE PHASE INPUT

C-Series

22.2. 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.

22.3. EXTERNAL INPUT PROTECTION
The unit is tested and approved for branch circuits up to 30A (UL) 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 10A B- or C-Characteristic breaker should be used.

22.4. OUTPUT CIRCUIT BREAKERS
Standard miniature circuit breakers (MCB’s or UL 1077 circuit breakers) are commonly used for AC-supply systems andmay also be used on 24V 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 size that 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, afast (magnetic) tripping of the MCB is desired. A quick shutdown within 10ms is necessary corresponding roughly tothe ride-through time of PLC's. This requires power supplies with high current reserves and large output capacitors.
Furthermore, the impedance of the faulty branch must be 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 crosssection and wire length.
Fig. 22-4 Test circuit

Power Supply

AC

MCB

+
Wire length

DC S1... Fault simulation switch

*)

Load

+
S1

-

Maximal wire length*) for a fast (magnetic) tripping:
0.75mm²
1.0mm²1.5mm²2.5mm²
C-2A
29m
40m
56m
82m
C-3A
26m
35m
50m
77m
C-4A
21m
28m
36m
53m
C-6A
8m
10m
14m
25m
C-8A
4m
7m
11m
18m
C-10A
1m
2m
3m
6m
B-6A
17m
24m
35m
53m
B-10A
12m
16m
23m
32m
B-13A
9m
13m
20m
29m
B-16A
4m
7m
9m
17m
B-20A
1m
1m
2m
2m

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

Apr. 2014 / Rev. 1.6 DS-CPS20.241-EN
All parameters are specified at 24V, 20A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0Germany

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CPS20.241, CPS20.241-C1
24V, 20A, SINGLE PHASE INPUT

C-Series

22.5. PARALLEL USE TO INCREASE OUTPUT POWER
CPS20.241 power supplies can be paralleled to increase the output power. The
output voltage of all power supplies shall be adjusted to the same value(±100mV) in “Single use” mode with the same load conditions on all units, orthe units can be left with the factory settings. After the adjustments, thejumper on the front of the unit shall be moved from “Single use” to “Paralleluse”, in order to achieve load sharing. The “Parallel use” mode regulates theoutput 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, theunit is in “Single use” mode. Factory setting is “Single use” mode.

Unit A

AC

DC

+
+

Unit B

AC

DC

Load

+
-

-

If more than three units are connected in parallel, a fuse or circuit breakerwith a rating of 30A or 32A is required on each output. Alternatively, a diode or redundancy module can also be
utilized.
Energize all units at the same time to avoid the overload HiccupPLUS mode. It also might be necessary to cycle the input
power (turn-off for at least five seconds), if the output was in HiccupPLUS mode due to overload or short circuits and therequired output current is higher than the current of one unit.
Keep an installation clearance of 15mm (left / right) between two power supplies and avoid installing the power
supplies on top of each other. Do not use power supplies in parallel in mounting orientations other than the standard
mounting orientation (terminals on bottom of the unit) or in any other condition where a derating of the output
current is required (e.g. altitude, above 60°C, …).
Pay attention that leakage current, EMI, inrush current, harmonics will increase when using multiple power supplies.

22.6. PARALLEL USE FOR REDUNDANCYPower supplies can be paralleled for redundancy to gain higher system availability. Redundant systems require acertain 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 20A are paralleled to build a 80A
redundant system. For N+1 redundancy the same restrictions apply as for increasing the output power, see also
chapter 22.5.
Please note: This simple way to build a redundant system does not cover failures such as an internal short circuit in
the secondary side of the power supply. In such a case, the defective unit becomes a load for the other power supplies
and the output voltage can not be maintained any more. This can be avoided by utilizing redundancy modules, whichhave decoupling devices (diodes or mosfets) included. Further information and wiring configurations can be found inchapter 21.3.
Recommendations for building redundant power systems:
a)
b)
c)
d)

Use separate input fuses for each power supply.
Set the power supply into “Parallel use” mode.
Monitor the individual power supply units. Therefore, use the DC-OK relay contact of the CPS20 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.

Apr. 2014 / Rev. 1.6 DS-CPS20.241-EN
All parameters are specified at 24V, 20A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0Germany

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CPS20.241, CPS20.241-C1
24V, 20A, SINGLE PHASE INPUT

C-Series

Unit A

22.7. SERIES OPERATIONACPower 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 the output voltage does not exceed 150Vdc. Voltages
with a potential above 60Vdc are not SELV any more and can be dangerous.
Such voltages must be installed with a protection against touching.

DC

+
+

Unit BAC

Earthing of the output is required when the sum of the output voltage isabove 60Vdc.

DC

Load

+
-

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

Earth(see notes)

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

22.8. INDUCTIVE AND CAPACITIVE LOADSThe unit is designed to supply any kind of loads, including capacitive and inductive loads. If extreme large capacitors,
such as EDLCs (electric double layer capacitors or “UltraCaps”) with a capacitance > 0.5F are connected to the output,
the unit might charge the capacitor in the HiccupPLUS mode (see chapter 6).

22.9. 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)b)

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

Use a 30A or 32A 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. 23mA when the power supply isswitched off (except in case a blocking diode is utilized).

Apr. 2014 / Rev. 1.6 DS-CPS20.241-EN
All parameters are specified at 24V, 20A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0Germany

24/26

CPS20.241, CPS20.241-C1
24V, 20A, SINGLE PHASE INPUT

C-Series

22.10. OPERATION ON TWO PHASESPower Supply
240V +10% max.

L1

The power supply can also be used on two-phases of a three-phase-system.
Such a phase-to-phase connection is allowed as long as the supplying
voltage is below 240V+10%.
L3

AC
L
Fuse

L2

internal
fuse

N
PE
DC

22.11. 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, 16A; (=80%) load is placed outside the box
230Vac
53.5°C (in the middle of the right side of the power supply with a distance of 2cm)
25.3°C
28.2K

Apr. 2014 / Rev. 1.6 DS-CPS20.241-EN
All parameters are specified at 24V, 20A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0Germany

25/26

CPS20.241, CPS20.241-C1
24V, 20A, SINGLE PHASE INPUT

C-Series22.12. MOUNTING ORIENTATIONSMounting orientations other than all terminals on the bottom require a reduction in continuous output power or alimitation in the maximum allowed ambient temperature. The amount of reduction influences the lifetime expectancyof the power supply. Therefore, two different derating curves for continuous operation can be found below:
Curve A1
Curve A2

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

Fig. 22-5
Mounting
Orientation A(Standardorientation)

Output Current

24A

A1

18

Power
Supply12
6
Ambient Temperature0

INPUT OUTPUT

10
Fig. 22-6
Mounting
Orientation B(Upside down)

20

30

50

40

60°C

Output Current

24A
A1

INPUT OUTPUT

18

A2

Power
Supply12
6
Ambient Temperature

010Fig. 22-7
Mounting
Orientation C(Table-top
mounting)

20

30

50

40

60°C

Output Current

24A
A1

18

A2

12
6
Ambient Temperature

0
10

50

40

60°C

24A

Power
Supply

18

A1

12

A2

6
Ambient Temperature

0
10

20

30

40

A1

A2

50

60°C

Output Current
INPUT OUTPUT

24A

Power
SupplyFig. 22-9
Mounting
Orientation E(Horizontal ccw)

30

Output Current
INPUT OUTPUT

Fig. 22-8
Mounting
Orientation D(Horizontal cw)

20

18
12
6

Ambient Temperature

0
10

20

30

40

50

60°C

Apr. 2014 / Rev. 1.6 DS-CPS20.241-EN
All parameters are specified at 24V, 20A, 230Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0Germany

26/26