dCl

dCp

Current Transducer CTSR 0.3-TP/SP14

IP R N = 300 mA

For the electronic measurement of current: DC, AC, pulsed…, with galvanic separation between
dCl primary circuitdand
Cpthethe secondary circuit.

Features

Applications● Closed loop (compensated) current transducer● Residual current measurement● Voltage output● Leakage current measurement in transformerless PV● Single supply voltage

inverters

R RM● PCB mounting● First human contact protection of PV arrays● Four integrated primary conductors.

● Failure detection in power sources

Special features● Symmetrical fault detection (e.g. after motor inverter)● No retention pin● Single phase or three phase nominal current measurement● Leakage current detection in stacked DC sources● Test winding included.

up to ±30 A per wire (DC or AC).

Advantages

Standards● High accuracy● EN 50178: 1997

● Very low offset drift over temperature● IEC 61010-1: 2010

● High overload capability● UL 508: 2010.

● High insulation capability● Reference pin with two modes, Ref IN and Ref OUT

Application Domains● Degauss and test functions● Industrial● Possibility to add up to four primary wires (diam. 4.2 mm● Suitable to fulfil VDE 0126-1-1, UL 1741 and IEC 62109-2.

max) in addition to the already integrated primary conductors.

N°97.H3.A2.014.0
11June2024/Version 9

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CTSR 0.3-TP/SP14
Safety⚠

CautionIf the device is used in a way that is not specified by the manufacturer, the protection provided by the device may be compromised.
Always inspect the electronics unit and connecting cable before using this product and do not use it if damaged.
Mounting assembly shall guarantee the maximum primary conductor temperature, fulfill clearance and creepage distance,
minimize electric and magnetic coupling, and unless otherwise specified can be mounted in any orientation.

Caution, risk of electrical shock
This transducer must be used in limited-energy secondary circuits SELV according to IEC 61010-1, in electric/electronic equipmentwith respect to applicable standards and safety requirements in accordance with the manufacturer’s operating specifications.
Use caution during installation and use of this product; certain parts of the module can carry hazardous voltages and high currents(e.g. power supply, primary conductor).
Ignoring this warning can lead to injury and or/or cause serious damage.
This transducer is a build-in device, whose hazardous live parts must be inaccessible after installation.
This transducer must be mounted in a suitable end-enclosure.
Besides make sure to have a distance of minimum 30 mm between the primary terminals of the transducer and other neighboring
components.
This transducer is a built-in device, not intended to be cleaned with any product. Nevertheless if the user must implement cleaning
or washing process, validation of the cleaning program has to be done by himself.

ESD susceptibility
The product is susceptible to be damaged from an ESD event and the personnel should be grounded when handling it.
Do not dispose of this product as unsorted municipal waste. Contact a qualified recycler for disposal.
Although LEM applies utmost care to facilitate compliance of end products with applicable regulations during LEM productdesign, use of this part may need additional measures on the application side for compliance with regulations regarding EMC andprotection against electric shock. Therefore LEM cannot be held liable for any potential hazards, damages, injuries or loss of life
resulting from the use of this product.

Underwriters Laboratory Inc. recognized component

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CTSR 0.3-TP/SP14

Absolute maximum ratings
Parameter

Symbol

Unit

Value

Maximum supply voltage

UC maxV

7

Maximum primary conductor temperature

TB max°C

110

Maximum primary withstand peak current (100 µs,
500 A/µs)

ÎP max

A

3300

RMS voltage for AC insulation test, 50 Hz, 1 min

Ud

V

35

Test current

IT

mA

300

Stresses above these ratings may cause permanent damage. Exposure to absolute maximum ratings for extended periods may
degrade reliability.

UL 508: Ratings and assumptions of certification
File # E189713 Volume: 2 Section: 3Standards● CSA C22.2 NO. 14-10 INDUSTRIAL CONTROL EQUIPMENT - Edition 11 - Revision Date 2011/08/01● UL 508 STANDARD FOR INDUSTRIAL CONTROL EQUIPMENT - Edition 17 - Revision Date 2010/04/15
Ratings
Parameter

SymbolPrimary involved potential*

Unit

Value

V AC/DC1000

Max surrounding air temperature

TA

°C

105

Primary current

IP

A

30

Secondary supply voltage

UC

V DC

5

Output voltage

Uout

V

0 to 5* Environmental: For use in Pollution degree 3.
Conditions of acceptability
When installed in the end-use equipment, consideration shall be given to the following:
1 - A suitable enclosure shall be provided in the end-use application.
2 - CTSR series is intended to be mounted on the printed wiring board of the end-use equipment.
3-P rimary feeder of the devices shall be connected after an overvoltage device or system which has been evaluated by theStandard for Transient Voltage Surge Suppressors, UL 1449.
4 - Jumpers of current transducers, CTSR X-TP series are intended to be PCB mounted.
Marking
Only those products bearing the UL or UR Mark should be considered to be Listed or Recognized and covered under UL's
Follow-Up Service. Always look for the Mark on the product.

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CTSR 0.3-TP/SP14

Insulation coordination
Parameter

Symbol

Unit

Value

RMS voltage for AC insulation test, 50 Hz, 1 min

Ud

kV

6

Impulse withstand voltage 1.2/50 µs

UNi

kV

11.2

Partial discharge RMS test voltage (qm < 10 pC)

Ut

kV

2.475

Clearance (pri. - pri.)

dCI

mm

6.7

Shortest distance throughair

Creepage distance (pri. - pri.)

dCp

mm

6.7

Shortest path along device
body

Clearance (pri. - sec.)

dCI

mm

13.5

Shortest distance throughair

Creepage distance (pri. - sec.)

dCp

mm

33.2

Shortest path along device
body

Comment

When mounted on a PCB (with recommended hole and pad diameters, see paragraph “PCB footprint”).
Clearance (pri. - pri.)

dCI

mm

5.6

Shortest distance throughair

Creepage distance (pri. - pri.)

dCp

mm

5.6

Shortest path along device
body

Clearance (pri. - sec.)

dCI

mm

12.5

Shortest distance throughair

Creepage distance (pri. - sec.)

dCp

mm

12.5

Shortest path along device
bodyCase material

-

-

V0

According to UL 94

Comparative tracking index

CTI

Application example-

Application example

600
V

1000

Reinforced insulation, CAT
III, PD2 non uniform fieldaccording to EN 50178

1500

Reinforced insulation, CAT
III, PD3 non uniform fieldaccording to EN 50178,
IEC 61010-

V

SymbolUnit

Min

Ambient operating temperature

TA

°C

−40

105

Ambient storage temperature

TA st

°C

−50

105

Mass

m

g

Environmental and mechanical characteristics
Parameter

Typ

Max

Comment

55

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Electrical data

CTSR 0.3-TP/SP14

At TA = 25 °C, UC = +5 V, output voltage referred to Uref, unless otherwise noted (see Min., Max., typical definition paragraph) in
page 6.

Parameter

SymbolUnit

Min

Primary nominal residual RMS current

IP R NmA

Primary residual current, measuring range

IP R M

mA−500

Supply voltage

UC

V

4.75

Current consumption

IC

Output voltage referred to GND(during Degauss cycle)

Typ

Max

Comment

300
500
5

5.25

mA

17.5

21.6

+IP (mA)/NS
With NS = 1000 turns−40 … 105 °C

Uout

V

0.3

0.5

1)

Output voltage referred to Uref
(Test current)

Uout

V

0.001

1.2

1.7

1)

Reference voltage @ IP = 0

Uref

V

2.495

2.5

2.505

External reference voltage

UE refV

2.3

Electrical offset current
referred to primary 2)

IO E

mA

−24

Temperature coefficient of Uref

TCUref

ppm/K

−50

50

−40 … 105 °C

Temperature coefficient of UO E @ IP = 0

TCUO E

ppm/K

−570

570

ppm/K of 2.5 V−40 … 105 °C

Nominal sensitivity

SN

V/A

Sensitivity error

εS

%

−1.6

1.6

RL > 500 kΩ

Sensitivity error with testing winding (±3 %)

εS

%

−3

3

RL > 500 kΩ

Temperature coefficient of S

TCS

ppm/K

−230

230

−40 … 85 °C

−400

400

−40 … 105 °C

Linearity errorεL% of IP R M

Number of turns (test winding)NT

Test current, measuring range

IT M

mA

Magnetic offset current (1000 × IP R N)
referred to primary

IO M

mA

17

Output RMS noise voltage (1 Hz ... 10 kHz)

Uno

mV

6

RL > 500 kΩ

Delay time to 10 % of the final output value
IP N step

tD 10

µs

7

RL > 500 kΩ,
di/dt > 5 A/µs

Delay time to 90 % of the final output value
IP N step

tD 90

µs

50

RL > 500 kΩ,
di/dt > 5 A/µs

Frequency bandwidth (−1 dB)

BW

kHz

3.5

RL > 500 kΩ

Error

ε

%

2)

3)

Notes:

Internal reference
Internal reference of

4

7

Uref input = 499 Ω 1)

24

4
0.5

0.5

1

20
−25

25

= (εS 2 + εL 2)1/2

1.9

See “Application information” section.
Only with a primary nominal residual current, see paragraph “Primary nominal residual current and primary nominal
1
		current”.
2
TCU O E
TCS

2
3)
×
2.5
×
T
-25
/
S
×
100
/
I
)
Total error @ TA and IP: ε tot (TA ) =  ε 2 + ( 6 × 100 × (TA -25))2 + (
(
)
A
N
P

6
1)
2)



11June2024/Version 910

10

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

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Definition of typical, minimum and maximum values

CTSR 0.3-TP/SP14

Minimum and maximum values for specified limiting and safety conditions have to be understood as such as well as values shownin “typical” graphs. On the other hand, measured values are part of a statistical distribution that can be specified by an interval withupper and lower limits and a probability for measured values to lie within this interval.
Unless otherwise stated (e.g. “100 % tested”), the LEM definition for such intervals designated with “min” and “max” is that theprobability for values of samples to lie in this interval is 99.73 %. For a normal (Gaussian) distribution, this corresponds to aninterval between −3 sigma and +3 sigma.
If “typical” values are not obviously mean or average values, those values are defined to delimit intervals with a probability of 68.27%, corresponding to an interval between −sigma and +sigma for a normal distribution.
Typical, minimum and maximum values are determined during the initial characterization of a product.

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CTSR 0.3-TP/SP14

Phase (°)

Relative sensitivity (dB)

Typical performance characteristics

Frequency (Hz)Uno (V)eno (dBVRMS/rtHz)

Figure 1: Frequency response

Figure 2: Output noise voltage spectral density

Figure 3: Output noise voltage, cumulated RMS

Figure 4: Typical step response

Figure 5: Typical step response

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CTSR 0.3-TP/SP14

Application information
Filtering, decoupling CTSR transducer
Supply voltage UC (5 V)

The CTSR transducers have internal decoupling capacitors, but in the case of a power supply track on the application PCB having
a high impedance, it is advised to provide local decoupling, 100 nF or more, located close to the transducer.

Reference Uref
Ripple present on the Uref pin can be filtered with a low value of capacitance because of the internal 499 ohm series resistance.
The CTSR transducers have an internal capacitor of 22 nF between Uref pin and Gnd pin and the maximum filter capacitance value
which could be added is 1 µF. Adding a larger decoupling capacitor will increase the activation delay of degauss.

Output Uout
The CTSR transducers have an internal low pass filter 470 ohm/22 nF; if a decoupling capacitor is added on Uout pin, the bandwidth
and the response time will be affected. In case of short circuit, the transducer CTSR can source or sink up to a maximum of 10
mA on its output Uout.

Using an external reference voltage
If the Uref pin of the transducer is not used it could be either left unconnected or filtered according to the previous paragraph“Reference Uref”.
The Uref pin has two modes Ref out and Ref In:• In the Ref out mode the 2.5 V internal precision reference is used by the transducer as the reference point for bipolarmeasurements; this internal reference is connected to the Uref pin of the transducer through a 499 ohms resistor. It
tolerates sink or source currents up to ± 5 mA, but the 499 ohms resistor prevents this current to exceed these limits.
• In the Ref In mode, an external reference voltage is connected to the Uref pin; this voltage is specified in the range 2.3
to 4 V and is directly used by the transducer as the reference point for measurements. The external reference voltage
Uref must be able:− 2.5
o either to source a typical current of U ref, the maximum value will be 3 mA when Uref = 4 V.
499

o or to sink a typical current of

2.5 − U ref, the maximum value will be 0.4 mA when Uref = 2.3 V.
499

The following graphs show how the measuring range of the transducer depends on the external reference voltage value Uref
(UC = 5 V).
600

IP R M 500 mA

IP R M (mA)

400
200
0
-200
-400
-600

2

3
Uref (V)4(mA)

Upper limit: IP=500 mA		
(Uref = 2.3 … 2.625 V)
1000
Upper limit: IP=−250 * Uref + 1156.25(Uref = 2.625 … 4 V)
800 I =−250 * U + 93.75
IPRM 850(UmA = 2.3 … 2.375 V)
Lower limit:
P
ref
ref
600
Lower limit: IP=−500 mA		
(Uref = 2.375 … 4 V)
400
200
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CTSR 0.3-TP/SP14

Primary nominal residual current and primary nominal current

The primary nominal residual current is the sum of the instantaneous values of all currents flowing through the aperture of thetransducer. The primary nominal current is the current flowing through any conductor placed into the aperture of the transducer.
The presence of a primary nominal current DC or AC leads to an additional uncertainty. For example, with a primary nominal
current of 30 A the uncertainty referred to primary is typical 4.3 mA.

Test winding
A test winding is wound around the compensation winding. It allows simulating a primary residual current to test the function of thetransducer. The output voltage Uout referred to Uref for a test current IT is below.
Uout − Uref= Sth * IT (test current) * 20
To fullfill the standard IEC 62109-2 with the transducer, the test winding must be used to verify the accuracy of the transducer
according to clause 4.4.4.15.1 and 4.8.3.5 of the IEC 62109-2 before each attempted re-start of the PV inverter. The current
injected in the test winding should be generated by a current source. When the test winding is not used, it must stay open. A
high voltage may be generated by the test winding when a fast transient primary current is applied to the transducer (transformer
effect); an additional protection is recommended in application PCB assembly if there is such a possibility.
: Uind at the test winding
di/dt

Uind

CTSR transducer in Test mode
When the Uref pin is forced at a low level voltage between 0 and 1 V and is maintained at this level, the output voltage Uout of CTSR
transducer exhibits a fixed value (see specification) as if it measured a primary test current. The activation time of test mode is min
30 ms. The CTSR transducer can be maintained in test mode as long as needed for checking that it is fully operating.

CTSR transducer in Degauss mode
The CTSR transducers go in degauss mode automatically at each power on or on demand by using the Uref pin.
At power on:
A degauss is automatically generated at each power on of the CTSR transducer; during degaussing the output voltage Uout ismaintained at 0.3 V typ. (max 0.5 V). After c.a. 110 ms, the output voltage Uout is released and takes the normal operation level in
relation with the measured primary current.
Using Uref pin:
When the pin Uref is released from the Low level voltage defined in the Test mode above, there is a rising edge on Uref which
generates an automatic degauss. The activation of degauss takes typically 40 µs after releasing Uref pin, then degauss lasts
typically 110 ms.
Uref
2.5 V

Summary of test and degauss modes at Uref = 2.5 V
Test mode

Measuring

Degauss mode

Measuring

1V

Uout referred to Uref
1.7 V

110 ms

0.7 V

Measured IP R

30 ms

−2 V
−2.5 V

Measured IP R
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CTSR 0.3-TP/SP14

Insulation around the CTSR transducer housing

Due to the joint between the case and the cover of the CTSR transducer, there is some isolation distance to respect when primaryconductors pass around the CTSR housing. The figure below shows the joint and the apertures where the clearance between thesecondary part inside the CTSR transducer and the surface of the housing is 3 mm (label E).

R RM

RM

Integrated primary conductors

The four integrated primary conductors have a diameter of 2.5 mm. The three conductors 7-12, 8-11 and 9-10 could be used as
the lines in a three phase system; the conductor 13-14 could be used either as the neutral in a three phase system or as a test
current conductor.
Primary conductor

Typical primary conductor resistance RP (mOhm)

7-12, 9-10

0.32

8-11

0.36

13-14

0.26

The maximum primary current per conductor must comply with the primary conductor temperature specified in paragraph “Absolute
maximum ratings”.

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CTSR 0.3-TP/SP14

PCB footprint
dCl

dCp

dCl

dCp

Assembly on PCB● Recommended PCB hole diameter					Maximum PCB thickness		● Wave soldering profile			No clean process only

1.2 mm for secondary pin
2.9 mm for primary pin
2.4 mmmaximum 260 °C, 10 s

Any primary conductor must be placed in the PCB at the requested insulation distance regarding the secondary side (see also
paragraph “Insulation around the CTSR transducer housing”).

R RM

RM

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CTSR 0.3-TP/SP14
Dimensions (in mm, general tolerance ±0.3 mm)

dCl

dCp

dCl

dCp

R RM

RM

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