CKSR 6-NP

## **Current transducer CKSR series** 

## _I_ **= 6, 15, 25, 50 A PN** 

## **Ref: CKSR 6-NP, CKSR 15-NP, CKSR 25-NP, CKSR 50-NP** 

**For the electronic measurement of current: DC, AC, pulsed..., with galvanic separation between the primary and the secondary circuit.** 

## **Features** 

- ●Closed loop (compensated) multi-range current transducer 

- ●Voltage output 

- ●Single supply 

- ●Single supply 

- ●Compact design for PCB mounting. 

## **Advantages** 

- ●Very low temperature coefficient of offset 

- ●Very good d _v_ /d _t_ immunity 

- ●Higher creepage distance/clearance 

- ●Reduced height 

- ●Reference pin with two modes: Ref IN and Ref OUT 

- ●Extended measuring range for unipolar measurement. 

## **Applications** 

- ●AC variable speed and servo motor drives 

- ●Static converters for DC motor drives 

- ●Battery supplied applications 

- ●Uninterruptible Power Supplies (UPS) 

- ●Switched Mode Power Supplies (SMPS) 

- ●Power supplies for welding applications 

- ●Solar inverters. 

## **Standards** 

- ●EN 50178: 1997 

- ●IEC 60950-1: 2006 

- ●IEC 61010-1: 2010 

- ●IEC 61326-1: 2012 

- ●UL 508: 2010. 

## **Application Domains** 

- ●Industrial 

- ●Automotive (list of additional tests available at 

- LEM_Auto_Tech_Support@lem.com). 

N°97.E7.09.000.7, N°97.E7.15.000.7, N°97.E7.19.000.7, N°97.E7.25.000.7 

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**CKSR series** 

## **Absolute maximum ratings** 

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Parameter Symbol Unit Value<br>**----- End of picture text -----**<br>


|**Parameter**|**Symbol**|**Unit**|**Value**|
|---|---|---|---|
|||||
|Supply voltage|_U_C|V|7|
|Primary conductor temperature|_T_B|°C|110|
|Maximum steady state primary current|_I_P|A|20 ×_I_PN|
|ESD rating, Human Body Model (HBM)|_U_ESD|kV|4|



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: 1 

## **Standards** 

- ●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** 

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Parameter Symbol Unit Value<br>**----- End of picture text -----**<br>


|**Parameter**|**Symbol**|**Unit**|**Value**|
|---|---|---|---|
|||||
|Primary involved potential||V AC/DC|1000|
|Max surrounding air temperature|_T_A|°C|105|
|Primary current|_I_P|A|According to series primary<br>currents|
|Secondary supply voltage|_U_C|V DC|7|
|Output voltage|_V_out|V|0 to 5|



## **Conditions of acceptability** 

_When installed in the end-use equipment, consideration shall be given to the following:_ 

- _1 - These devices must be mounted in a suitable end-use enclosure._ 

- _4 - CKSR series intended to be mounted on the printed circuit wiring board of the end-use equipment (with a minimum CTI of 100)._ 

- _5 - CKSR series shall be used in a pollution degree 2._ 

- _8 - Low voltage circuits are intended to be powered by a circuit derived from an isolating source (such as transformer, optical isolator, limiting impedance or electro-mechanical relay) and having no direct connection back to the primary circuit (other than through the grounding means)._ 

- _11 - CKSR series: based on results of temperature tests, in the end-use application, a maximum of 100 °C cannot be_ 

   - _exceeded at soldering joint between primary coil pin and soldering point (corrected to the appropriate evaluated max. surrounding air)._ 

## **Marking** 

Only those products bearing the UL or UR Mark should be considered to be Listed or Recognized and covered under UL's FollowUp Service. Always look for the Mark on the product. 

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**CKSR series** 

## **Insulation coordination** 

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Parameter Symbol Unit Value Comment<br>**----- End of picture text -----**<br>


|**Parameter**|**Symbol**|**Unit**|**Value**|**Comment**|
|---|---|---|---|---|
||||||
|Rms voltage for AC insulation test, 50 Hz, 1 min|_U_d|kV|4.3||
|Impulse withstand voltage 1.2/50 µs|_U_W|kV|8||
|Partial discharge extinction rms voltage @ 10 pC|_U_e|V|1000||
|Clearance distance (pri. - sec.)|_d_CI|mm|8.2|Shortest distance through<br>air|
|Creepage distance (pri. - sec.)|_d_Cp|mm|8.2|Shortest path along device<br>body|
|Case material|_-_|-|V0 according<br>to UL 94||
|Comparative tracking index|_CTI_||600||
|Application example|-|-|300 V CAT III<br>PD2|Reinforced insulation, non<br>uniform feld according to<br>IEC 61010-1|
|Application example|-|-|600 V CAT III<br>PD2|Reinforced insulation, non<br>uniform feld according to<br>EN 50178|
|Application example|-|-|1000 V CAT III<br>PD2|<br>Simple insulation, non<br>uniform feld according to<br>EN 50178|



## **Environmental and mechanical characteristics** 

|**Parameter**|**Symbol**|**Unit**|**Min**|**Typ**|**Max**|**Comment**|
|---|---|---|---|---|---|---|
|Ambient operating temperature|_T_A|°C|−40||105||
|Ambient storage temperature|_T_S|°C|−55||105||
|Mass|_m_|g||9|||



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**CKSR series** 

## **Electrical data CKSR 6-NP** 

At _T_ A = 25 °C, _U_ C = +5 V, _N_ P = 1 turn, _R_ L = 10 kΩ, internal reference, unless otherwise noted (see Min, Max, typ. definition paragraph in page 13). 

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Parameter Symbol Unit Min Typ Max Comment<br>**----- End of picture text -----**<br>


|**Parameter**|**Symbol**|**Unit**|**Min**|**Typ**|**Typ**|**Max**|**Max**|**Comment**|
|---|---|---|---|---|---|---|---|---|
||||||||||
|Primary nominal rms current|_I_PN|A||6||||Apply derating<br>accordingto fg. 25|
|Primary current, measuring range|_I_PM|A|−20|||20|||
|Number of primary turns|_N_P|-||1, 2, 3, 4|||||
|Supply voltage|_U_C|V|4.75||5|5.25|||
|Current consumption|_I_C|mA||15 +|_I_P (mA)<br> _N_S|20 +|_I_P (mA)<br>|_N_S= 1731 turns|
||||||||<br> _N_S||
|Reference voltage @_I_P= 0 A|_V_ref|V|2.495||2.5|2.505||Internal reference|
|External reference voltage|_V_ref|V|0|||4|||
|Output voltage|_V_out|V|0.375|||4.625|||
|Output voltage @_I_P= 0 A|_V_out|V|||_V_ref||||
|Electrical offset voltage|_V_OE|mV|−5.3|||5.3||100 % tested<br>_V_out−_V_ref|
|Electrical offset current referred to<br>primary|_I_OE|mA|−51|||51||100 % tested|
|Temperature coeffcient of_V_ref|_TCV_ref|ppm/K|||±5|±50||Internal reference|
|Temperature coeffcient<br>of_V_out@_I_P= 0 A|_TCV_out|ppm/K|||±6|±14||ppm/K of 2.5 V<br>−40 °C … 105 °C<br>(at ±6 Sigma)|
|Theoretical sensitivity|_G_th|mV/A||104.2||||625 mV/_I_PN|
|Sensitivity error|_ε_G|%|−0.7|||0.7||100 % tested|
|Temperature coeffcient of_G_|_TCG_|ppm/K||||±40||−40 °C … 105 °C|
|Linearity error|_ε_L|% of_I_PN|−0.1|||0.1|||
|Magnetic offset current @_I_P= 0 and<br>specifed_R_M, after an overload of 10 ×_I_PN|_I_OM|A|−0.1|||0.1|||
|Output rms current noise spectral density<br>100 Hz … 100 kHz referred to primary|<br>_i_no|µA/Hz½||20||||_R_L= 1 kΩ|
|Peak-peak output ripple at oscillator<br>frequency_f_= 450 kHz (typ.)|-|mV||40||160||_R_L= 1 kΩ|
|Reaction time @ 10 % of_I_PN|_t_ra|µs||||0.3||_R_L= 1 kΩ<br>d_i_/d_t_= 18 A/µs|
|Response time @ 90 % of_I_PN|_t_r|µs||||0.3||_R_L= 1 kΩ<br>d_i_/d_t_= 18 A/µs|
|Frequency bandwidth (±1 dB)|_BW_|kHz|200|||||_R_L= 1 kΩ|
|Frequency bandwidth (±3 dB)|_BW_|kHz|300|||||_R_L= 1 kΩ|
|Overall accuracy|_X_G|% of_I_PN||||1.7|||
|Overall accuracy @_T_A= 85 °C (105 °C)|_X_G|% of_I_PN||||2.2 (2.4)|||
|Accuracy|_X_|% of_I_PN||||0.8|||
|Accuracy @_T_A= 85 °C (105 °C|_X_|% of_I_PN||||1.4 (1.6)|||



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**CKSR series** 

## **Electrical data CKSR 15-NP** 

At _T_ A = 25 °C, _U_ C = +5 V, _N_ P = 1 turn, _R_ L = 10 kΩ, internal reference, unless otherwise noted (see Min, Max, typ. definition paragraph in page 13). 

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Parameter Symbol Unit Min Typ Max Comment<br>**----- End of picture text -----**<br>


|**Parameter**|**Symbol**|**Unit**|**Min**|**Typ**|**Typ**|**Max**|**Max**|**Comment**|
|---|---|---|---|---|---|---|---|---|
||||||||||
|Primary nominal rms current|_I_PN|A||15||||Apply derating<br>according to fg. 26|
|Primary current, measuring range|_I_PM|A|−51|||51|||
|Number of primary turns|_N_P|-||1, 2, 3, 4|||||
|Supply voltage|_U_C|V|4.75||5|5.25|||
|Current consumption|_I_C|mA||15 +|_I_P (mA)<br> _N_S|20 +|_I_P (mA)<br>|_N_S= 1731 turns|
||||||||<br> _N_S||
|Reference voltage @_I_P= 0 A|_V_ref|V|2.495||2.5|2.505||Internal reference|
|External reference voltage|_V_ref|V|0|||4|||
|Output voltage|_V_out|V|0.375|||4.625|||
|Output voltage @_I_P= 0 A|_V_out|V|||_V_ref||||
|Electrical offset voltage|_V_OE|mV|−2.21|||2.21||100 % tested<br>_V_out−_V_ref|
|Electrical offset current referred to<br>primary|_I_OE|mA|−53|||53||100 % tested|
|Temperature coeffcient of_V_ref|_TCV_ref|ppm/K|||±5|±50||Internal reference|
|Temperature coeffcient of_V_out@_I_P= 0 A|_TCV_OUT|ppm/K||±2.3||±6||ppm/K of 2.5 V<br>−40 °C … 105 °C<br>(at ±6 Sigma)|
|Theoretical sensitivity|_G_th|mV/A||41.67||||625 mV/_I_PN|
|Sensitivity error|_ε_G|%|−0.7|||0.7||100 % tested|
|Temperature coeffcient of_G_|_TCG_|ppm/K||||±40||−40 °C … 105 °C|
|Linearity error|_ε_L|% of_I_PN|−0.1|||0.1|||
|Magnetic offset current @_I_P= 0 and<br>specifed_R_M, after an overload of 10 ×_I_PN|_I_OM|A|−0.1|||0.1|||
|Output rms current noise spectral density<br>100 Hz … 100 kHz referred to primary|<br>_i_no|µA/Hz½||20||||_R_L= 1 kΩ|
|Peak-peak output ripple at oscillator<br>frequency_f_= 450 kHz (typ.)|-|mV||15||60||_R_L= 1 kΩ|
|Reaction time @ 10 % of_I_PN|_t_ra|µs||||0.3||_R_L= 1 kΩ<br>d_i_/d_t_= 44 A/µs|
|Response time @ 90 % of_I_PN|_t_r|µs||||0.3||_R_L= 1 kΩ<br>d_i_/d_t_= 44 A/µs|
|Frequency bandwidth (±1 dB)|_BW_|kHz|200|||||_R_L= 1 kΩ|
|Frequency bandwidth (±3 dB)|_BW_|kHz|300|||||_R_L= 1 kΩ|
|Overall accuracy|_X_G|% of_I_PN||||1.2|||
|Overall accuracy @_T_A= 85 °C (105 °C)|_X_G|% of_I_PN||||1.5 (1.7)|||
|Accuracy|_X_|% of_I_PN||||0.8|||
|Accuracy @_T_A= 85 °C (105 °C)|_X_|% of_I_PN||||1.2 (1.3)|||



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**CKSR series** 

## **Electrical data CKSR 25-NP** 

At _T_ A = 25 °C, _U_ C = +5 V, _N_ P = 1 turn, _R_ L = 10 kΩ, internal reference, unless otherwise noted (see Min, Max, typ. definition paragraph in page 13). 

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Parameter Symbol Unit Min Typ Max Comment<br>**----- End of picture text -----**<br>


|**Parameter**|**Symbol**|**Unit**|**Min**|**Typ**|**Typ**|**Max**|**Max**|**Comment**|
|---|---|---|---|---|---|---|---|---|
||||||||||
|Primary nominal rms current|_I_PN|A|||25|||Apply derating<br>according to fg. 27|
|Primary current, measuring range|_I_PM|A|−85|||85|||
|Number of primary turns|_N_P|-||1,|2, 3, 4||||
|Supply voltage|_U_C|V|4.75||5|5.25|||
|Current consumption|_I_C|mA||15 +|_I_P (mA)<br> _N_S|20 +|_I_P (mA)<br> _N_S|_N_S= 1731 turns|
|Reference voltage @_I_P= 0 A|_V_ref|V|2.495||2.5|2.505||Internal reference|
|External reference voltage|_V_ref|V|0|||4|||
|Output voltage|_V_out|V|0.375|||4.625|||
|Output voltage @_I_P= 0 A|_V_out|V|||_V_ref||||
|Electrical offset voltage|_V_OE|mV|−1.35|||1.35||100 % tested_V_out−_V_ref|
|Electrical offset current referred to<br>primary|_I_OE|mA|−54|||54||100 % tested|
|Temperature coeffcient of_V_ref|_TCV_ref|ppm/K|||±5|±50||Internal reference|
|Temperature coeffcient of_V_out@<br>_I_P= 0 A|_TCV_out|ppm/K|||±1.4|±4||ppm/K of 2.5 V<br>−40 °C … 105 °C<br>(at ±6 Sigma)|
|Theoretical sensitivity|_G_th|mV/A|||25|||625 mV/_I_PN|
|Sensitivity error|_ε_G|%|−0.7|||0.7||100 % tested|
|Temperature coeffcient of_G_|_TCG_|ppm/K||||±40||−40 °C … 105 °C|
|Linearity error|_ε_L|% of_I_PN|−0.1|||0.1|||
|Magnetic offset current @_I_P= 0<br>and specifed_R_M, after an overload<br>of 10 ×_I_PN|_I_OM|A|−0.1|||0.1|||
|Output rms current noise spectral<br>density 100 Hz … 100 kHz referred<br>to primary|_i_no|µA/Hz½|||20|||_R_L= 1 kΩ|
|Peak-peak output ripple at oscillator<br>frequency_f_= 450 kHz (typ.)|-|mV|||10|40||_R_L= 1 kΩ|
|Reaction time @ 10 % of_I_PN|_t_ra|µs||||0.3||_R_L= 1 kΩ d_i_/d_t_= 68 A/µs|
|Response time @ 90 % of_I_PN|_t_r|µs||||0.3||_R_L= 1 kΩ d_i_/d_t_= 68 A/µs|
|Frequency bandwidth (±1 dB)|_BW_|kHz|200|||||_R_L= 1 kΩ|
|Frequency bandwidth (±3 dB)|_BW_|kHz|300|||||_R_L= 1 kΩ|
|Overall accuracy|_X_G|% of_I_PN||||1|||
|Overall accuracy @_T_A= 85 °C<br>(105 °C)|_X_G|% of_I_PN||||1.35 (1.45)|||
|Accuracy|_X_|% of_I_PN||||0.8|||
|Accuracy @_T_A= 85 °C (105 °C)|_X_|% of_I_PN||||1.15 (1.25)|||



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**CKSR series** 

## **Electrical data CKSR 50-NP** 

At _T_ A = 25 °C, _U_ C = +5 V, _N_ P = 1 turn, _R_ L = 10 kΩ, internal reference, unless otherwise noted (see Min, Max, typ. definition paragraph in page 13). 

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|**Parameter**|**Symbol**|**Unit**|**Min**|**Typ**|**Typ**|**Max**|**Max**|**Comment**|
|---|---|---|---|---|---|---|---|---|
||||||||||
|Primary nominal rms current|_I_PN|A|||50|||Apply derating<br>according to fg. 28|
|Primary current, measuring range|_I_PM|A|−150|||150|||
|Number of primary turns|_N_P|-||1,|2, 3, 4||||
|Supply voltage|_U_C|V|4.75||5|5.25|||
|Current consumption|_I_C|mA||15 +|_I_P (mA)<br> _N_S|20 +|_I_P (mA)<br> _N_S|_N_S= 966 turns|
|Reference voltage @_I_P= 0 A|_V_ref|V|2.495||2.5|2.505||Internal reference|
|External reference voltage|_V_ref|V|0|||4|||
|Output voltage|_V_out|V|0.375|||4.625|||
|Output voltage @_I_P= 0 A|_V_out|V|||_V_ref||||
|Electrical offset voltage|_V_OE|mV|−0.725|||0.725||100 % tested<br>_V_out−_V_ref|
|Electrical offset current referred to<br>primary|_I_OE|mA|−58|||58||100 % tested|
|Temperature coeffcient of_V_ref|_TCV_ref|ppm/K|||±5|±50||Internal reference|
|Temperature coeffcient of_V_out@_I_P= 0 A|_TCV_out|ppm/K|||±0.7|±3||ppm/K of 2.5 V<br>−40 °C … 105 °C<br>(at ±6 sigma)|
|Theoretical sensitivity|_G_th|mV/A|||12.5|||625 mV/_I_PN|
|Sensitivity error|_ε_G|%|−0.7|||0.7||100 % tested|
|Temperature coeffcient of_G_|_TCG_|ppm/K||||±40||−40 °C … 105 °C|
|Linearity error|_ε_L|% of_I_PN|−0.1|||0.1|||
|Magnetic offset current (10 ×_I_PN) referred<br>to primary|_I_OM|A|−0.1|||0.1|||
|Output rms current noise spectral density<br>100 Hz … 100 kHz referred to primary|_i_no|µA/Hz½|||20|||_R_L= 1 kΩ|
|Peak-peak output ripple at oscillator<br>frequency = 450 kHz (Typ.)|-|mV|||5|20||_R_L= 1 kΩ|
|Reaction time @ 10 % of_I_PN|_t_ra|µs||||0.3||_R_L= 1 kΩ<br>d_i_/d_t_= 100 A/µs|
|Response time @ 90 % of_I_PN|_t_r|µs||||0.3||_R_L= 1 kΩ<br>d_i_/d_t_= 100 A/µs|
|Frequency bandwidth (±1 dB)|_BW_|kHz|200|||||_R_L= 1 kΩ|
|Frequency bandwidth (±3 dB)|_BW_|kHz|300|||||_R_L= 1 kΩ|
|Overall accuracy|_X_G|% of_I_PN||||0.9|||
|Overall accuracy @_T_A= 85 °C (105 °C)|_X_G|% of_I_PN||||1.2 (1.3)|||
|Accuracy|_X_|% of_I_PN||||0.8|||
|Accuracy @_T_A= 85 °C (105 °C)|_X_|% of_I_PN||||1.1 (1.3)|||



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**CKSR series** 

## **Typical performance characteristics CKSR 6-NP** 

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0.1<br>0.05<br>0<br>-0.05<br>-0.1<br>-6 0 6<br>I P (A)<br>)<br>PN<br>I<br>Linearity error  (% of<br>**----- End of picture text -----**<br>


_Figure 1: Linearity error_ 

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7 3.2<br>6 3.1<br>5 3.0<br>4 2.9<br>I P = 6 A<br>3 2.8<br>2 I P 2.7<br>1 2.6<br>0 2.5<br>-1 2.4<br>-0.5 0 0.5 1 1.5 2<br>t  (µs)<br>V out<br> (A) P  (V)<br>I out<br>V<br>**----- End of picture text -----**<br>


_Figure 3: Step response_ 

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10000<br>1000<br>100<br>10<br>1<br>0.1<br>1.E+1 1.E+2 1.E+3 1.E+4 1.E+5 1.E+6 1.E+7<br>Frequency (Hz)<br>)<br>½<br> (μA/Hz<br>i no<br>**----- End of picture text -----**<br>


_Figure 5: Input referred ouput noise current spectral density_ 

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1 1<br>0.8 I  P = 6 A 0<br>0.6 -1<br>0.4 -2<br>0.2 -3<br>0 -4<br>-0.2 -5<br>-0.4 -6<br>-0.6 Relative -7<br>-0.8 Sensitivity -8<br>Phase<br>-1 -9<br>100 1000 10000 100000 1000000<br>Frequency (Hz)<br>Phase (°)<br>Relative Sensitivity (dB)<br>**----- End of picture text -----**<br>


_Figure 2: Frequency response_ 

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7 3.2<br>6 3.1<br>5 3.0<br>4 2.9<br>I P = 6 A<br>3 2.8<br>2 I P 2.7<br>1 2.6<br>0 2.5<br>-1 2.4<br>-2 0 2 4 6 8 10<br>t  (µs)<br>Figure 4: Step response<br>800 3.6<br>600<br>3.4<br>400<br>3.2<br>200<br>0 20 kV/μs 3.0<br>-200<br>2.8<br>-400<br>2.6<br>-600<br>-800 2.4<br>-1 0 1 2 3 4 5<br>t  (µs)<br>V ref<br>V p<br>V out<br>V out<br>P<br>I<br> (V)<br> (A)<br>out<br>V<br> (V) P<br>V<br> (V)<br>out<br>V<br>Primary Voltage<br>**----- End of picture text -----**<br>


_Figure 6:_ d _v/_ d _t_ 

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LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice 

21December2015/version 13 

**CKSR series** 

## **Typical performance characteristics CKSR 15-NP** 

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0.1 1 1<br>0.8 I P = 15 A 0<br>0.6 -1<br>0.05<br>0.4 -2<br>0.2 -3<br>0 0 -4<br>-0.2 -5<br>-0.4 -6<br>-0.05<br>-0.6 Relative -7<br>-0.8 Sensitivity -8<br>Phase<br>-0.1 -1 -9<br>-15 0 15 100 1000 10000 100000 1000000<br>I P (A) (A) Frequency (Hz)<br>Figure 7: Linearity error  Figure 8: Frequency response<br>17.5 3.2 17.5 3.2<br>15 3.1 15 3.1<br>12.5 3.0 12.5 3.0<br>10 2.9 10 2.9<br>I P = 15  A I P = 15  A<br>7.5 2.8 7.5 2.8<br>5 I P 2.7 5 I P 2.7<br>2.5 2.6 2.5 2.6<br>0 2.5 0 2.5<br>-2.5 2.4 -2.5 2.4<br>-0.5 0 0.5 1 1.5 2 -2 0 2 4 6 8 10<br>t  (µs) t  (µs)<br>Figure 9: Step response  Figure 10: Step response<br>10000<br>800 3.6<br>600<br>1000 3.4<br>400<br>3.2<br>100 200<br>0 20 kV/μs 3.0<br>10<br>-200<br>2.8<br>-400<br>1<br>2.6<br>-600<br>0.1 -800 2.4<br>1.E+1 1.E+2 1.E+3 1.E+4 1.E+5 1.E+6 1.E+7<br>-1 0 1 2 3 4 5<br>Frequency (Hz) t  (µs)<br>V p<br>V out<br>V ref<br>V out V out<br>)<br>PN<br>I<br>Phase (°)<br>Linearity error  (% of  Relative Sensitivity (dB)<br> (V)<br> (A)   (A)   (V)<br>V out I P out<br>V<br> (V)<br>P<br>)  V<br>½<br> (V)<br>out<br> (μA/Hz V<br>i no<br>Primary Voltage<br>P<br>I<br>**----- End of picture text -----**<br>


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0.1<br>0.05<br>0<br>-0.05<br>-0.1<br>-15 0 15<br>I P (A) (A)<br>)<br>PN<br>I<br>Linearity error  (% of<br>**----- End of picture text -----**<br>


_Figure 7: Linearity error_ 

_Figure 9: Step response_ 

_Figure 11: Input referred ouput noise current spectral density_ 

_Figure 12:_ d _v/_ d _t_ 

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**CKSR series** 

## **Typical performance characteristics CKSR 25-NP** 

**==> picture [476 x 576] intentionally omitted <==**

**----- Start of picture text -----**<br>
1 1<br>0.1<br>0.8 I P = 25 A 0<br>0.6 -1<br>0.05 0.4 -2<br>0.2 -3<br>0 0 -4<br>-0.2 -5<br>-0.4 -6<br>-0.05 -0.6 Relative -7<br>-0.8 Sensitivity -8<br>Phase<br>-0.1 -1 -9<br>-25 0 25 100 1000 10000 100000 1000000<br>Frequency (Hz)<br>I P (A)<br>Figure 13: Linearity error  Figure 14: Frequency response<br>29.2 3.2 29.2 3.2<br>25.0 3.1 25.0 3.1<br>20.8 3.0 20.8 3.0<br>16.7 2.9 16.7 2.9<br>I P = 25 A I P = 25 A<br>12.5 2.8 12.5 2.8<br>8.3 I P 2.7 8.3 I P 2.7<br>4.2 2.6 4.2 2.6<br>0.0 2.5 0.0 2.5<br>-4.2 2.4 -4.2 2.4<br>-0.5 0 0.5 1 1.5 2 -2 0 2 4 6 8 10<br>t  (µs) t  (µs)<br>Figure 15: Step response  Figure 16: Step response<br>10000<br>800 3.6<br>600<br>1000 3.4<br>400<br>3.2<br>100 200<br>0 20 kV/μs 3.0<br>10<br>-200<br>2.8<br>-400<br>1<br>2.6<br>-600<br>0.1 -800 2.4<br>1.E+1 1.E+2 1.E+3 1.E+4 1.E+5 1.E+6 1.E+7<br>-1 0 1 2 3 4 5<br>Frequency (Hz) t  (µs)<br>V out V out<br>V P<br>V out<br>V ref<br>)<br>PN<br>I<br>Phase (°)<br>Relative Sensitivity (dB)<br>Linearity error  (% of<br> (A)   (V)  (A)  (V)<br>I P out I P out<br>V V<br> (V)<br>P<br>)  V<br>½<br> (V)<br>out<br> (μA/Hz V<br>i no<br>Primary Voltage<br>**----- End of picture text -----**<br>


_Figure 13: Linearity error_ 

_Figure 15: Step response_ 

_Figure 17: Input referred ouput noise current spectral density_ 

_Figure 18: dv/dt_ 

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**CKSR series** 

## **Typical performance characteristics CKSR 50-NP** 

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**----- Start of picture text -----**<br>
0.1<br>0.05<br>0<br>-0.05<br>-0.1<br>-50 0 50<br>I P (A)<br>)<br>PN<br>I<br>Linearity error  (% of<br>**----- End of picture text -----**<br>


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**----- Start of picture text -----**<br>
1 1<br>0.8 I P = 50 A 0<br>0.6 -1<br>0.4 -2<br>0.2 -3<br>0 -4<br>-0.2 -5<br>-0.4 -6<br>-0.6 Relative -7<br>-0.8 Sensitivity -8<br>Phase<br>-1 -9<br>100 1000 10000 100000 1000000<br>Frequency (Hz)<br>Phase (°)<br>Relative Sensitivity (dB)<br>**----- End of picture text -----**<br>


_Figure 19: Linearity error_ 

_Figure 20: Frequency response_ 

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**----- Start of picture text -----**<br>
58.3 3.2 58.3 3.2<br>50.0 3.1 50.0 3.1<br>41.7 3.0 41.7 3.0<br>33.3 2.9 33.3 2.9<br>I P = 50 A I  P = 50 A<br>25.0 2.8 25.0 2.8<br>16.7 2.7 16.7 I P 2.7<br>8.3 2.6 8.3 2.6<br>0.0 2.5 0.0 2.5<br>-8.3 2.4 -8.3 2.4<br>-0.5 0 0.5 1 1.5 2 -2 0 2 4 6 8 10<br>t  (µs) t  (µs)<br>Figure 21: Step response  Figure 22: Step response<br>10000 800 3.6<br>600<br>1000 3.4<br>400<br>3.2<br>100 200<br>0 20 kV/μs 3.0<br>10<br>-200<br>2.8<br>-400<br>1<br>2.6<br>-600<br>0.1 -800 2.4<br>1.E+1 1.E+2 1.E+3 1.E+4 1.E+5 1.E+6 1.E+7<br>-1 0 1 2 3 4 5<br>Frequency (Hz) t  (µs)<br>I P<br>V out<br>V P<br>V out<br>V ref<br>V out<br>P<br>I<br> (A) P  (V)  (A)   (V)<br>I out out<br>V V<br> (V)<br>P<br>)  V<br>½<br> (V)<br>out<br> (μA/Hz V<br>i no<br>Primary Voltage<br>**----- End of picture text -----**<br>


_Figure 23: Input referred ouput noise current spectral density Figure 24: dv/dt_ 

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**CKSR series** 

## **Maximum continuous DC primary current** 

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**----- Start of picture text -----**<br>
40 90<br>35 CKSR 6-NP 80 CKSR 15-NP<br>70<br>30<br>60<br>25<br>50<br>20<br>40<br>15<br>30<br>10<br>20<br>5 10<br>0 0<br>0 20 40 60 80 100 120 0 20 40 60 80 100 120<br>T A (° C) T A (° C)<br>Figure 25: I P  vs T A  for CKSR 6-NP   Figure 26: I P  vs T A  for CKSR 15-NP<br>90 160<br>80 140 CKSR 50-NP<br>70<br>120<br>60<br>100<br>50<br>80<br>40<br>60<br>30<br>20 CKSR 25-NP 40<br>10 20<br>0 0<br>0 20 40 60 80 100 120 0 20 40 60 80 100 120<br>T A (° C) T A (° C)<br>(A) (A)<br>P P<br>I I<br>(A) (A)<br>P P<br>I I<br>**----- End of picture text -----**<br>


_Figure 27: I_ P _vs T_ A _for CKSR 25-NP Figure 28: I_ P _vs T_ A _for CKSR 50-NP_ 

The maximum continuous DC primary current plot shows the boundary of the area for which all the following conditions are true: ● _I_ P < _I_ PM 

- ●Junction temperature _T_ J < 125 °C 

- ●Primary conductor temperature < 110 °C 

- ●Resistor power dissipation < 0.5 × rated power 

## **Frequency derating** 

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**----- Start of picture text -----**<br>
AC Derating<br>1.25<br>1<br>0.75<br>0.5<br>0.25<br>0<br>10 100 1k 10k 100k 1M<br>f  (Hz)<br>max  DC current<br>max rms AC current /<br>**----- End of picture text -----**<br>


_Figure 29: Maximum rms AC primary current / maximum DC primary current vs frequency_ 

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**CKSR series** 

## **Performance parameters definition** 

## **Ampere-turns and amperes** 

The transducer is sensitive to the primary current linkage _Θ_ P (also called ampere-turns). 

- _Θ_ P= _N_ P _I_ P(At) 

- Where _N_ P the number of primary turn (depending on the connection of the primary jumpers) 

Caution: As most applications will use the transducer with only one single primary turn ( _N_ P = 1), much of this datasheet is written in terms of primary current instead of current linkages. However, the ampere-turns (At) unit is used to emphasis that current linkages are intended and applicable. 

## **Transducer simplified model** 

The static model of the transducer at temperature _T_ A is: _V_ out = _G Θ_ P + _ε_ 

## **Sensitivity and linearity** 

To measure sensitivity and linearity, the primary current (DC) is cycled from 0 to _I_ P, then to − _I_ P and back to 0 (equally spaced _I_ P/10 steps). 

The sensitivity _G_ is defined as the slope of the linear regression line for a cycle between ± _I_ PN. 

The linearity error _ε_ L is the maximum positive or negative difference between the measured points and the linear regression line, expressed in % of _I_ PN. 

## **Magnetic offset** 

The magnetic offset current _I_ OM is the consequence of a current on the primary side (“memory effect” of the transducer’s ferromagnetic parts). It is included in the linearity figure but can be measured individually. 

It is measured using the following primary current cycle. _I_ OM depends on the current value _I_ P1( _I_ P1 > _I_ PN). 

In which _ε_ = 

_V_ OE + _V_ O _T_ ( _T_ A) + _ε_ G ⋅ _Θ_ P ⋅ _G_ + _ε_ L( _Θ_ P max) ⋅ _Θ_ P max ⋅ _G_ + _TCG_ ⋅ ( _T_ A − 25) ⋅ _Θ_ P ⋅ _G_ 

With: _Θ_ P = _N_ P _I_ P :the input ampere-turns (At) Please read above warning. _Θ_ P max :the maxi input ampere-turns that have been applied to the transducer (At) _V_ out :the secondary voltage (V) _T_ A :the ambient temperature (°C) _V_ OE :the electrical offset voltage (V) _V_ O _T_ ( _T_ A) :the temperature variation of _V_ O at temperature _T_ A (V) _G_ :the sensitivity of the transducer (V/At) _ε_ G :the sensitivity error _ε_ L ( _Θ_ P max) :the linearity error for _Θ_ P max 

**==> picture [198 x 153] intentionally omitted <==**

**----- Start of picture text -----**<br>
I = V out ( t 1 ) [−] V out ( t 2 ) · 1<br>OM 2 G th<br>I P (DC)<br>I P1<br>t 2<br>0 A<br>                     t 1                          t<br>- I P1<br>**----- End of picture text -----**<br>


This model is valid for primary ampere-turns _Θ_ P between − _Θ_ P max and + _Θ_ P max only. 

## **Definition of typical, minimum and maximum values** 

_Figure 30: Current cycle used to measure magnetic and electrical offset (transducer supplied)_ 

Minimum and maximum values for specified limiting and safety conditions have to be understood as such as well as values shown in “typical” graphs. 

On the other hand, measured values are part of a statistical distribution that can be specified by an interval with upper 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 the probability for values of samples to lie in this interval is 99.73 %. 

For a normal (Gaussian) distribution, this corresponds to an interval 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 the product. 

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**CKSR series** 

## **Performance parameters definition (continued)** 

## **Electrical offset** 

The electrical offset voltage _V_ OE can either be measured when the ferro-magnetic parts of the transducer are: 

- ●completely demagnetized, which is difficult to realize, 

- ●or in a known magnetization state, like in the current cycle shown in figure 30. 

Using the current cycle shown in figure 30, the electrical offset is: 

**==> picture [100 x 21] intentionally omitted <==**

The temperature variation _V_ O _T_ of the electrical offset voltage _V_ OE is the variation of the electrical offset from 25 °C to the considered temperature: 

**==> picture [119 x 10] intentionally omitted <==**

Note: the transducer has to be demagnetized prior to the application of the current cycle (for example with a demagnetization tunnel). 

**==> picture [240 x 85] intentionally omitted <==**

**----- Start of picture text -----**<br>
U C<br>R M V out<br>V ref<br>**----- End of picture text -----**<br>


## **Overall accuracy** 

The overall accuracy at 25 °C _X_ G is the error in the − _I_ PN … + _I_ PN range, relative to the rated value _I_ PN. It includes: 

- ●the electrical offset _V_ OE 

- ●the sensitivity error _ε_ G 

- ●the linearity error _ε_ L (to _I_ PN) 

The magnetic offset is part of the overall accuracy. It is taken into account in the linearity error figure provided the transducer has not been magnetized by a current higher than 

_I_ PN. 

## **Response and reaction times** 

The response time _t_ r and the reaction time _t_ ra are shown in figure 32. 

Both depend on the primary current d _i_ /d _t_ . They are measured at nominal ampere-turns. 

**==> picture [187 x 131] intentionally omitted <==**

**----- Start of picture text -----**<br>
I<br>100 %<br>90 %<br>V out<br>I p<br>t r<br>10 %<br>t ra t<br>**----- End of picture text -----**<br>


_Figure 31: Test connection_ 

_Figure 32: Response time tr and reaction time tra_ 

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**CKSR series** 

## **Application information** 

## **Filtering and decoupling** 

## **Supply voltage** _U_ **C** 

The fluxgate oscillator draws current pulses of up to 30 mA at a rate of ca. 900 kHz. Significant 900 kHz voltage ripple on _U_ C can indicate a power supply with high impedance. At these frequencies the power supply rejection ratio is low, and the ripple may appear on the transducer output _V_ out  and reference _V_ ref. The transducer has internal decoupling capacitors, but in the case of a power supply with high impedance, it is advised to provide local decoupling (100 nF or more, located close to the transducer) 

## **Output** _V_ **out** 

The output _V_ out has a very low output impedance of typically 2 Ohms; it can drive 100 pF directly. Adding series Rf = 100 Ohms allows much larger capacitive loads. Empirical  evaluation may be necessary to obtain optimum results. The minimum load resistance on _V_ out is 1 kOhm. 

## **Reference** _V_ **ref** 

Ripple present on the reference output can be filtered with a low value of capacitance because of the internal 680 Ohm series resistance. The maximum filter capacitance value is 1 µF. 

**==> picture [240 x 85] intentionally omitted <==**

**----- Start of picture text -----**<br>
U C<br>R M V out<br>V ref<br>**----- End of picture text -----**<br>


## **Total Primary Resistance** 

The primary resistance is 0.72 mΩ per conductor. 

In the following table, examples of primary resistance according to the number of primary turns. 

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**----- Start of picture text -----**<br>
Number of Primary Recommended<br>resistance<br>primary turns RP [m Ω ] connections<br>        9     8     7    6    out<br>1 0.18<br>              in     2     3    4     5<br>        9     8     7    6    out<br>2 0.72<br>              in     2     3    4     5<br>        9     8     7    6    out<br>4 2.88<br>              in     2     3    4     5<br>**----- End of picture text -----**<br>


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**CKSR series** 

## **Application information (continued)** 

## **External reference voltage** 

If the Ref pin of the transducer is not used it could be either left unconnected or filtered according to the previous paragraph “Reference _V_ ref”. 

The Ref pin has two modes Ref IN and Ref OUT: 

- ●In the Ref OUT mode the 2.5 V internal precision reference is used by the transducer as the reference point for bipolar measurements; this internal reference is connected to the Ref pin of the transducer through a 680 Ohms resistor. it tolerates sink or source currents up to ±5 mA, but the 680 Ohms resistor prevents this current to exceed these limits. 

- ●In the Ref IN mode, an external reference voltage is connected to the Ref pin; this voltage is specified in the range 0 to 4 V and is directly used by the transducer as the reference point for measurements. The external reference voltage _V_ ref must be able: 

_Vref_ − 5.2 - either to source a typical current of 680 

, the maximum value will be 2.2 mA typ. when _V_ ref = 4 V. 

5.2 − _Vref_ 680 

- or to sink a typical current of , the maximum value will be 3.68 mA typ. when _V_ ref = 0 V. 

The following graphs show how the measuring range of each transducer version depends on the external reference voltage value _V_ ref. 

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**----- Start of picture text -----**<br>
50<br>40<br>30<br>20<br>10<br>0<br>-10<br>-20<br>-30<br>-40 CKSR 6<br>-50<br>0 1 2 3 4<br>V ref  (V)<br> (A)<br> I  P<br>**----- End of picture text -----**<br>


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**----- Start of picture text -----**<br>
100<br>80<br>60<br>40<br>20<br>0<br>-20<br>-40<br>-60<br>-80 CKSR 15<br>-100<br>0 1 2 3 4<br>V ref  (V)<br> (A)<br>P<br>I<br>**----- End of picture text -----**<br>


Upper limit: _I_ P = −9.6 * _V_ ref + 44.4 ( _V_ ref = 0 … 4 V) Lower limit: _I_ P = −9.6 * _V_ ref + 3.6 ( _V_ ref = 0 … 4 V) 

Upper limit: _I_ P = −24 * _V_ ref + 111 ( _V_ ref = 1.29 … 4 V) Upper limit: _I_ P = 80 ( _V_ ref = 0 … 1.29 V) Lower limit: _I_ P = −24 * _V_ ref + 9 ( _V_ ref = 0 … 3.7 V) Lower limit: _I_ P = −80 ( _V_ ref = 3.7 … 4 V) 

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21December2015/version 13 

**CKSR series** 

## **External reference voltage (continued)** 

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**----- Start of picture text -----**<br>
100<br>80<br>60<br>40<br>20<br>0<br>-20<br>-40<br>-60<br>-80 CKSR 25<br>-100<br>0 1 2 3 4<br>V ref  (V)<br> (A)<br>P<br>I<br>**----- End of picture text -----**<br>


Upper limit: _I_ P = −40 * _V_ ref + 185 ( _V_ ref = 2.5 … 4 V) Upper limit: _I_ P = 85 ( _V_ ref = 0 … 2.5 V) Lower limit: _I_ P = −40 * _V_ ref + 15 ( _V_ ref = 0 … 2.5 V) Lower limit: _I_ P = −85 ( _V_ ref = 2.5 … 4 V) 

**==> picture [218 x 169] intentionally omitted <==**

**----- Start of picture text -----**<br>
200<br>150<br>100<br>50<br>0<br>-50<br>-100<br>-150 CKSR 50<br>-200<br>0 1 2 3 4<br>V ref  (V)<br> (A)<br>P<br>I<br>**----- End of picture text -----**<br>


Upper limit: _I_ P = −80 * _V_ ref  + 370 ( _V_ ref = 2.75 … 4 V) Upper limit: _I_ P = 150 ( _V_ ref = 0 … 2.75 V) Lower limit: _I_ P = −80 * _V_ ref + 30 ( _V_ ref = 0 … 2.25 V) Lower limit: _I_ P = −150 ( _V_ ref = 2.25 … 4 V) 

Example with _V_ ref = 1.65 V: 

- ●The 6 A version has a measuring range from −12.24 A to +28.5 A 

- ●The 15 A version has a measuring range from −30.6 A to +71.4 A 

- ●The 25 A version has a measuring range from −51 A to +85 A 

- ●The 50 A version has a measuring range from −102 A to +150 A 

Example with Vref = 0 V: 

- ●The 6 A version has a measuring range from +3.6 A to +44.4 A 

- ●The 15 A version has a measuring range from +9 A to +80 A 

- ●The 25 A version has a measuring range from +15 A to +85 A 

- ●The 50 A version has a measuring range from +30 A to +150 A 

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**CKSR series** 

## **PCB footprint** 

**==> picture [206 x 205] intentionally omitted <==**

## **Assembly on PCB** 

- ●Recommended PCB hole diameter 1.3 mm for primary pin 

● 0.8 mm for secondary pin ●Maximum PCB thickness 2.4 mm ●Wave soldering profile maximum 260 ~~°~~ C for 10 s 

- No clean process o ~~n~~ ly. 

## **Safety** 

This transducer must be used ~~i~~ n limited-energy secondary circuits according to IEC 61010-1. 

This transducer must be used in electric/electronic equipment with respect to applicable standards and safety requirements in accordance with the manufacturer’s operating instructions. 

Caution, risk of electrical shock 

When operating the transducer, certain parts of the module can carry hazardous voltage (eg. primary busbar, power supply). Ignoring this warning can lead to injury and/or cause serious damage.This transducer is a build-in device, whose conducting parts must be inaccessible after installation. A protective housing or additional shield could be used. Main supply must be able to be disconnected. 

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**CKSR series** 

## **Dimensions** (in mm. General linear tolerance ±0.25 mm) 

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**----- Start of picture text -----**<br>
Connection ou t<br>680<br>a U C o 1h<br>10k<br>I R M i V GNO out 13<br>4 V ref<br>= 62<br>**----- End of picture text -----**<br>


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