LESR 15-NP KIT

Current Transducer LESR series IP N = 6, 15, 25, 50 A Ref: LESR 6-NP, LESR 15-NP, LESR 25-NP, LESR 50-NP For the electronic measurement of current: DC, AC, pulsed..., with galvanic separation between the primary and the secondary circuit. Features Applications ●● Closed loop multi-range current transducer ●● AC variable speed and servo motor drives ●● Voltage output ●● Static converters for DC motor drives ●● Unipolar supply voltage ●● Battery supplied applications ●● Compact design for PCB mounting. ●● Uninterruptible Power Supplies (UPS) Advantages ●● Very low offset drift ●● Very good dv/dt immunity ●● Switched Mode Power Supplies (SMPS) ●● Power supplies for welding applications ●● Solar inverters. ●● CASR footprint compatible Standards ●● Reference pin with two modes: Ref IN and Ref OUT ●● IEC 61800-1: 1997 ●● Extended measuring range for unipolar measurement. ●● IEC 61800-2: 2015 ●● IEC 61800-3: 2004 ●● IEC 61800-5-1: 2007 ●● IEC 62109-1: 2010 ●● IEC 62477-1: 2012 ●● UL 508:2013. Application Domain ●● Industrial. N°97.O8.09.000.0, N°97.O8.15.000.0, N°97.O8.19.000.0, N°97.O8.25.000.0 2August2017/Version 2 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice Page 1/20 www.lem.com LESR series Absolute maximum ratings Parameter Symbol Unit Value Maximum supply voltage UC max V 7 Maximum primary conductor temperature TB max °C 110 Maximum primary current IP max A 20 × IPN UESD max kV 4 Maximum electrostatic discharge voltage 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: 11 Standards ●● CSA C22.2 NO. 14-10 INDUSTRIAL CONTROL EQUIPMENT - Date 2011/08/01 ●● UL 508 STANDARD FOR INDUSTRIAL CONTROL EQUIPMENT - Date 2013 Ratings Parameter Symbol Primary involved potential Unit Value V AC/DC 600 Max surrounding air temperature TA °C 105 Primary current IP A According to series primary currents Secondary supply voltage UC V DC 7 Output voltage Vout 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. 2-T  he terminals have not been evaluated for field wiring. 3 - The LES, LESR, LKSR, LPSR, LXS and LXSR Series shall be used in a pollution degree 2 environment or better. 4-L  ow voltage circuits are intended to be powered by a circuit derived from an isolating source (such as a 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). 5-T  hese devices are intended to be mounted on the printed wiring board of the end-use equipment (with a minimum CTI of 100). 6-L  ES, LESR, LKSR and LPSR Series: based on results of temperature tests, in the end-use application, a maximum of 110°C cannot be exceeded on the primary jumper. 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. Page 2/20 2August2017/Version 2 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice www.lem.com LESR series Insulation coordination Parameter Symbol Unit Value RMS voltage for AC insulation test, 50 Hz, 1 min Ud kV 4.3 Impulse withstand voltage 1.2/50 μs ÛW kV 8 Insulation resistance RINS GΩ 18 Partial discharge RMS test voltage (qm < 10 pC) Ut kV 1.65 Clearance (pri. - sec.) dCI Creepage distance (pri. - sec.) dCp Case material - measured at 500 V DC See dimensions drawing on page 19 mm - CTI Comparative tracking index Comment V0 according to UL 94 600 Application example V 300 V CAT III, PD2 Reinforced insulation, non uniform field according to IEC 61800-5-1 Application example V 600 V CAT III, PD2 Basic insulation, non uniform field according to IEC 61800-5-1 Environmental and mechanical characteristics Parameter Symbol Unit Min Ambient operating temperature TA °C −40 105 Ambient storage temperature TS °C −55 125 Mass m g Typ Max Comment 10 Page 3/20 2August2017/Version 2 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice www.lem.com LESR series Electrical data LESR 6-NP At TA = 25 °C, UC = +5 V, NP = 1 turn, RL = 10 kΩ internal reference, unless otherwise noted (see Definition of typical, minimum and maximum values paragraph in page 18). Parameter Symbol Unit Primary nominal RMS current IP N A Primary current, measuring range IP M A Number of primary turns NP Supply voltage UC V Current consumption IC mA Reference voltage @ IP = 0 A Vref V 2.485 External reference voltage Vref V 0.5 Output voltage Vout V 0.25 Output voltage @ IP = 0 A Vout V Electrical offset voltage VO E mV −5 5 100 % tested Vout − Vref Electrical offset current referred to primary IO E mA −48 48 100 % tested Temperature coefficient of Vref @ IP = 0 A TCVref ppm/K ±70 Internal reference Temperature coefficient of Vout @ IP = 0 A TCVout ppm/K ±14 ppm/K of 2.5 V −40 °C … 105 °C Theoretical sensitivity Gth mV/A Sensitivity error εG % TCG ppm/K εL % of IP N −0.1 0.1 Magnetic offset current (10 × IP N) referred to primary IO M mA −25 25 Output RMS voltage noise spectral density 100 … 100 kHz referred to primary eno µV/Hz½ Output voltage noise DC … 10 kHz DC … 100 kHz DC … 1 MHz Vno mVpp Reaction time @ 10 % of IP N tra µs 0.3 RL = 1 kΩ, di/dt = 50 A/µs Step response time to 90 % of IP N tr µs 0.4 RL = 1 kΩ, di/dt = 50 A/µs Frequency bandwidth (±1 dB) BW kHz Overall accuracy XG % of IP N 1.25 Overall accuracy @ TA = 85 °C (105 °C) XG % of IP N 1.25 (1.5) Accuracy X % of IP N 0.5 Accuracy @ TA = 85 °C (105 °C) X % of IP N 0.75 (1) Temperature coefficient of G Linearity error Min Typ Max Comment Apply derating according to fig. 21 6 −20 20 1, 2, 3 4.75 5 17 + 5.25 I (mA) N P S 2.5 20 + I (mA) N P S 2.515 NS = 2000 turns Internal reference 2.75 4.75 with UC = +5 V Vref 104.2 −0.2 625 mVIP N 0.2 100 % tested ±40 −40 °C … 105 °C 7 10.5 13.4 13.6 300 RL = 1 kΩ Page 4/20 2August2017/Version 2 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice www.lem.com LESR series Electrical data LESR 15-NP At TA = 25 °C, UC = +5 V, NP = 1 turn, RL = 10 kΩ internal reference, unless otherwise noted (see Definition of typical, minimum and maximum values paragraph in page 18). Parameter Symbol Unit Min Primary nominal RMS current IP N A Primary current, measuring range IP M A Number of primary turns NP Supply voltage UC V Current consumption IC mA Reference voltage @ IP = 0 A Vref V 2.485 External reference voltage Vref V 0.5 2.75 Output voltage Vout V 0.25 4.75 with UC = +5 V 100 % tested Vout − Vref Typ Max Comment Apply derating according to fig. 22 15 −51 51 1, 2, 3 4.75 5 17 + 5.25 I (mA) N P S 2.5 20 + I (mA) N P S 2.515 NS = 2000 turns Internal reference Output voltage @ IP = 0 A Vout V Electrical offset voltage VO E mV −1.75 1.75 Electrical offset current referred to primary IO E mA −42 42 100 % tested Temperature coefficient of Vref @ IP = 0 A TCVref ppm/K ±70 Internal reference Temperature coefficient of Vout @ IP = 0 A TCVout ppm/K ±6 ppm/K of 2.5 V −40 °C … 105 °C Theoretical sensitivity Gth mV/A Sensitivity error εG % TCG ppm/K εL % of IP N Temperature coefficient of G Linearity error Vref 41.67 −0.2 625 mVIP N 0.2 100 % tested ±40 −40 °C … 105 °C −0.1 0.1 −45 45 Magnetic offset current (10 × IP N) referred to primary IO M Output RMS voltage noise spectral density 100 … 100 kHz referred to primary eno µV/Hz½ Output voltage noise DC … 10 kHz DC … 100 kHz DC … 1 MHz Vno mVpp Reaction time @ 10 % of IP N tra µs 0.3 RL = 1 kΩ, di/dt = 50 A/µs Step response time to 90 % of IP N tr µs 0.4 RL = 1 kΩ, di/dt = 50 A/µs Frequency bandwidth (±3 dB) BW kHz Overall accuracy XG % of IP N 0.75 Overall accuracy @ TA = 85 °C (105 °C) XG % of IP N 0.75 (1) Accuracy X % of IP N 0.5 Accuracy @ TA = 85 °C (105 °C) X % of IP N 0.65 (0.75) 3.5 4.5 5.7 6.3 300 RL = 1 kΩ Page 5/20 2August2017/Version 2 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice www.lem.com LESR series Electrical data LESR 25-NP At TA = 25 °C, UC = +5 V, NP = 1 turn, RL = 10 kΩ internal reference, unless otherwise noted (see Definition of typical, minimum and maximum values paragraph in page 18). Parameter Symbol Unit Min Primary nominal RMS current IP N A Primary current, measuring range IP M A Number of primary turns NP Supply voltage UC V Current consumption IC mA Reference voltage @ IP = 0 A Vref V 2.485 External reference voltage Vref V 0.5 2.75 Output voltage Vout V 0.25 4.75 Typ Max Comment Apply derating according to fig. 23 25 −85 85 1, 2, 3 4.75 5 17 + 5.25 I (mA) N P S 2.5 20 + I (mA) N P S 2.515 NS = 2000 turns Internal reference with UC = +5 V Output voltage @ IP = 0 A Vout V Electrical offset voltage VO E mV −1 1 100 % tested Vout − Vref Electrical offset current referred to primary IO E mA −40 40 100 % tested Temperature coefficient of Vref @ IP = 0 A TCVref ppm/K ±70 Internal reference Temperature coefficient of Vout @ IP = 0 A TCVout ppm/K ±4 ppm/K of 2.5 V −40 °C … 105 °C Theoretical sensitivity Gth mV/A Sensitivity error εG % TCG ppm/K Temperature coefficient of G Linearity error Vref 25 −0.2 625 mVIP N 0.2 100 % tested ±40 −40 °C … 105 °C εL % of IP N −0.1 0.1 Magnetic offset current (10 × IP N) referred to primary IO M mA −60 60 Output RMS voltage noise spectral density 100 … 100 kHz referred to primary eno µV/Hz½ Output voltage noise DC … 10 kHz DC … 100 kHz DC … 1 MHz Vno mVpp Reaction time @ 10 % of IP N tra µs 0.3 RL = 1 kΩ, di/dt = 50 A/µs Step response time to 90 % of IP N tr µs 0.4 RL = 1 kΩ, di/dt = 50 A/µs Frequency bandwidth (±3 dB) BW kHz Overall accuracy XG % of IP N 0.8 Overall accuracy @ TA = 85 °C (105 °C) XG % of IP N 0.85 (0.9) Accuracy X % of IP N 0.5 Accuracy @ TA = 85 °C (105 °C) X % of IP N 0.65 (0.75) 1.8 2.6 3.9 5.1 300 RL = 1 kΩ Page 6/20 2August2017/Version 2 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice www.lem.com LESR series Electrical data LESR 50-NP At TA = 25 °C, UC = +5 V, NP = 1 turn, RL = 10 kΩ internal reference, unless otherwise noted (see Definition of typical, minimum and maximum values paragraph in page 18). Parameter Symbol Unit Primary nominal RMS current IP N A Primary current, measuring range IP M A Number of primary turns NP Supply voltage UC V Current consumption IC mA Reference voltage @ IP = 0 A Vref V 2.485 External reference voltage Vref V 0.5 Output voltage Vout V 0.25 Output voltage @ IP = 0 A Vout V Electrical offset voltage VO E mV Electrical offset current referred to primary IO E mA Temperature coefficient of Vref @ IP = 0 A TCVref Temperature coefficient of Vout @ IP = 0 A Theoretical sensitivity Sensitivity error Min Typ Max Comment Apply derating according to fig. 24 50 −150 150 1, 2, 3 4.75 5 17 + 5.25 I (mA) N P S 2.5 20 + I (mA) N P S 2.515 NS = 1600 turns Internal reference 2.75 4.75 with UC = +5 V −0.7 0.7 100 % tested Vout − Vref −56 56 100 % tested ppm/K ±70 Internal reference TCVout ppm/K ±3 ppm/K of 2.5 V −40 °C … 105 °C Gth mV/A εG % Vref 12.5 −0.2 625 mVIP N 0.2 100 % tested ±40 −40 °C … 105 °C TCG ppm/K εL % of IP N −0.1 0.1 Magnetic offset current (10 × IP N) referred to primary IO M mA −60 60 Output RMS voltage noise spectral density 100 … 100 kHz referred to primary eno µV/Hz½ Output voltage noise DC … 10 kHz DC … 100 kHz DC … 1 MHz Vno mVpp Reaction time @ 10 % of IP N tra µs 0.3 RL = 1 kΩ, di/dt = 50 A/µs Step response time to 90 % of IP N tr µs 0.4 RL = 1 kΩ, di/dt = 50 A/µs Frequency bandwidth (±3 dB) BW kHz Overall accuracy XG % of IP N 0.7 Overall accuracy @ TA = 85 °C (105 °C) XG % of IP N 0.7 (0.8) Accuracy X % of IP N 0.5 Accuracy @ TA = 85 °C (105 °C) X % of IP N 0.65 (0.75) Temperature coefficient of G Linearity error 1.7 2.4 3.2 4.8 300 RL = 1 kΩ Page 7/20 2August2017/Version 2 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice www.lem.com LESR series Typical performance characteristics LESR 6-NP 0.1 4 Rel. Sensitivity 20 Phase 2 10 0 0 0 −0.05 −0.1 −6 −2 −10 −4 −20 −6 −30 −8 −40 −10 1 10 6 I [A] Phase [°] Relative Sensitivity [dB] Linearity Error [ % IP N ] 0.05 2 3 10 P Figure 1: Linearity error 4 −50 6 10 5 10 10 Frequency [Hz] 10 Figure 2: Frequency response 6 0.625 0.417 Vout−Vref (V) 4 IP (A) IP Vout−Vref 2 0.208 0 0 100 200 300 t (µs) 400 500 Figure 3: Step response 10000 3.5 3.4 600 1000 3.3 100 10 3.1 400 VP Vout Vref 200 3.0 2.9 Vout (V) Primary Voltage VP (V) eno (µVRMS/ Hz1/2 ) 3.2 2.8 2.7 2.6 1 2.5 1 10 2 10 3 10 4 10 fc (Hz) 5 10 Figure 4: Output noise voltage spectral density 6 10 7 10 2.4 20 kV/µs 0 0 1 2 3 t (µs) 4 5 6 2.3 7 2.2 8 Figure 5: dv/dt Page 8/20 2August2017/Version 2 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice www.lem.com LESR series Typical performance characteristics LESR 15-NP 0.1 0 −0.05 −0.1 −15 2 10 0 0 −2 −10 −4 −20 −6 −30 −8 −40 −10 1 10 15 I [A] Rel. Sensitivity 20 Phase Phase [°] Relative Sensitivity [dB] Linearity Error [ % IP N ] 0.05 4 2 3 10 Figure 6: Linearity error 4 −50 6 10 5 10 10 Frequency [Hz] P 10 Figure 7: Frequency response 15 0.625 0.417 Vout−Vref (V) 10 IP (A) IP Vout−Vref 5 0.208 0 0 100 200 300 t (µs) 400 500 Figure 8: Step response 3.5 10000 3.4 600 3.3 3.2 100 10 3.1 400 VP Vout Vref 200 3.0 2.9 Vout (V) Primary Voltage VP (V) eno (µVRMS/ Hz1/2 ) 1000 2.8 2.7 2.6 2.5 1 1 10 2 10 3 10 4 fc (Hz) 10 Figure 9: Output noise voltage spectral density 5 10 6 10 2.4 20 kV/µs 0 0 1 2 3 t (µs) 4 5 6 2.3 7 2.2 8 Figure 10: dv/dt Page 9/20 2August2017/Version 2 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice www.lem.com LESR series Typical performance characteristics LESR 25-NP 0.1 4 Rel. Sensitivity 20 Phase 2 10 0 0 0 −0.05 −0.1 −25 −2 −10 −4 −20 −6 −30 −8 −40 −10 1 10 25 IP [A] Phase [°] Relative Sensitivity [dB] Figure 11: Linearity error 2 3 10 4 −50 6 10 5 10 10 Frequency [Hz] 10 Figure 12: Frequency response 30 0.750 25 0.625 20 0.500 15 0.375 Vout−Vref (V) Linearity Error [ % IP N ] 0.05 IP (A) IP Vout−Vref 10 0.250 5 0.125 0 0 100 200 300 t (µs) 400 500 600 Figure 13: Step response 3.5 10000 3.4 600 3.3 3.2 100 10 3.1 400 VP Vout Vref 200 3.0 2.9 Vout (V) Primary Voltage VP (V) eno (µVRMS/ Hz1/2 ) 1000 2.8 2.7 2.6 2.5 1 1 10 2 10 3 10 4 fc (Hz) 10 5 10 Figure 14: Output noise voltage spectral density 6 10 2.4 20 kV/µs 0 0 1 2 3 t (µs) 4 5 6 2.3 7 2.2 8 Figure 15: dv/dt Page 10/20 2August2017/Version 2 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice www.lem.com LESR series Typical performance characteristics LESR 50-NP 0.1 4 Rel. Sensitivity 20 Phase 2 10 0 0 0 −0.05 −0.1 −50 −2 −10 −4 −20 −6 −30 −8 −40 −10 1 10 50 IP [A] Phase [°] Relative Sensitivity [dB] Figure 16: Linearity error 2 3 10 4 −50 6 10 5 10 10 Frequency [Hz] 10 Figure 17: Frequency response 30 0.750 25 0.625 20 0.500 15 0.375 IP (A) IP Vout−Vref 10 Vout−Vref (V) Linearity Error [ % IP N ] 0.05 0.250 5 0.125 0 0 100 200 300 t (µs) 400 500 Figure 18: Step response 3.5 10000 3.4 600 3.3 3.2 100 10 3.1 400 3.0 VP Vout Vref 200 2.9 Vout (V) Primary Voltage VP (V) eno (µVRMS/ Hz1/2 ) 1000 2.8 2.7 2.6 2.5 1 1 10 2 10 3 10 4 fc (Hz) 10 Figure 19: Output noise voltage spectral density 5 10 6 10 2.4 20 kV/µs 0 0 1 2 3 t (µs) 4 5 6 2.3 7 2.2 8 Figure 20: dv/dt Page 11/20 2August2017/Version 2 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice www.lem.com LESR series Maximum continuous DC primary current 40 100 35 90 30 80 70 60 20 IP (A) IP (A) 25 15 50 40 30 10 20 5 0 10 0 20 40 60 80 TA (°C) 100 120 0 140 100 40 60 80 TA (°C) 100 120 140 100 120 140 160 90 140 80 120 70 100 IP (A) 60 IP (A) 20 Figure 22: IP vs TA for LESR 15-NP Figure 21: IP vs TA for LESR 6-NP 50 40 80 60 30 40 20 20 10 0 0 0 20 40 60 80 TA (°C) 100 120 0 140 Figure 23: IP vs TA for LESR 25-NP 0 20 40 60 80 TA (°C) Figure 24: IP vs TA for LESR 50-NP The maximum continuous DC primary current plot shows the boundary of the area for which all the following conditions are true: -- IP < IP M -- Junction temperature TJ < 125 °C -- Primary conductor temperature < 110 °C -- Max power dissipation of internal resistors < 0.5 × resistors nominal power Frequency derating Ip AC derating max AC rms current / max DC rms current 1.33 1 0.66 0.33 0 10 100 1k fc (Hz) 10k 100k 1M Figure 25: Maximum RMS AC primary current / maximum DC primary current vs frequency Page 12/20 2August2017/Version 2 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice www.lem.com LESR series Performance parameters definition Ampere-turns and amperes Magnetic offset The transducer is sensitive to the primary current linkage ΘP (also called ampere-turns). The magnetic offset current IO M is the consequence of a current on the primary side (“memory effect” of the transducer’s ferromagnetic parts). It is measured using the following primary current cycle. IO M depends on the current value IP1 (IP1 > IP M). ΘP = NP⋅IP (At) Where NP is 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 (NP = 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 TA is: IS = G⋅ΘP + ε In which ε = IO E + IO T (TA) + εG ⋅ΘP⋅G + εL (ΘP max)⋅ΘP max⋅G + TCG⋅(TA−25)⋅ΘP⋅G With: ΘP = NP⋅IP ΘP max IS TA IO E IO T (TA) G TCG εG εL(ΘP max) : primary current linkage (At) : max primary current linkage applied to the transducer : secondary current (A) : ambient operating temperature (°C) : electrical offset current (A) : temperature variation of IO at temperature TA (°C) : sensitivity of the transducer (V/At) : temperature coefficient of G IO M = Vout(t1) − Vout(t2) 1 · 2 Gth IP (DC) IP N 0A −IP1 t t2 t1 Ip(3) Ip(t 3) Figure 26: C  urrent cycle used to measure magnetic and electrical offset (transducer supplied) : sensitivity error : linearity error for ΘP max This model is valid for primary ampere-turns ΘP between −ΘP max and +ΘP max only. Sensitivity and linearity To measure sensitivity and linearity, the primary current (DC) is cycled from 0 to IP, then to −IP and back to 0 (equally spaced IP/10 steps). The sensitivity G is defined as the slope of the linear regression line for a cycle between ±IP N. The linearity error εL is the maximum positive or negative difference between the measured points and the linear regression line, expressed in % of IP N. Page 13/20 2August2017/Version 2 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice www.lem.com LESR series Performance parameters definition Electrical offset Overall accuracy The electrical offset voltage VO E can either be measured when The overall accuracy at 25 °C XG is the error in the −IP N … +IP N the ferro-magnetic parts of the transducer are: range, relative to the rated value IP N. It includes: ●● Completely demagnetized, which is difficult to realize, ●● the electrical offset VO E ●● or in a known magnetization state, like in the current cycle shown in figure 26. ●● the sensitivity error εG Using the current cycle shown in figure 26, the electrical offset ●● the linearity error εL (to IP N) is: VO E = Vout (t1) + Vout (t2) Response and reaction times 2 VO T (T) = VO E (T) − VO E (25° C) The response time tr and the reaction time tra are shown in figure The temperature variation VO T of the electrical offset voltage 28. VO E is the variation of the t1) + Vout (t2) offset from 25 °C to the Both depend on the primary current di/dt. They are measured at Vout (electrical VO E = considered temperature: 2 nominal ampere-turns. VO T (T) = VO E (T) − VO E (25° C) I Note: the transducer has to be demagnetized prior to the application of the current cycle (for example with a demagnetization tunnel). 100 % 90 % Vout Ip tr +UC 10 % Vout RM Vref RL tra t Figure 28: Response time tr and reaction time tra Figure 27: Test connection +UC RM Vout Vref Page 14/20 2August2017/Version 2 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice www.lem.com LESR series Application information Filtering and decoupling Reference Vref Like the output Vout, the Vref has a very low output impedance of typically 1 Ohm; it can drive capacitive loads nF +U of up to 100 directly. Adding series resistance Rf of several tenths of Ohms V R allows much larger capacitive loads Cf (higher than 1 µF). R V Empirical evaluation may be necessary to obtain optimum results. The minimum load resistance on Vref is 10 kOhms. Supply voltage UC C The transducer has internal decoupling capacitors, but in the case of a power supply with high impedance, it is highly recommended to provide local decoupling (100 nF or more, located close to the transducer) as it may reduce disturbance on transducer output Vout and reference Vref due to high varying primary current. The transducer power supply rejection ratio is low at high frequency. M out ref L +UC Output Vout RM The output Vout has a very low output impedance of typically 1 Ohm; it can drive capacitive loads of up to 100 nF directly. Adding series resistance Rf of several tenths of Ohms allows much larger capacitive loads Cf (higher than 1 µF). Empirical evaluation may be necessary to obtain optimum results. The minimum load resistance on Vout is 1 kOhm. Vout Vref Figure 29: filtered Vout connection 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. Number Primary Output of Nominal voltage primary RMS Vout turns current Primary resistance RP [mΩ] ±IP N 0.24 Recommended connections 10 1 2 3 ±IP N/2 ±IP N/3 Vref ±0.625 Vref ±0.625 1.08 Vref ±0.625 2.16 9 8 OUT IN 1 2 3 10 9 8 OUT IN 1 10 2 9 3 8 OUT IN 1 2 3 Page 15/20 2August2017/Version 2 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice www.lem.com LESR series External reference voltage The REF pin can be used either as a reference voltage output or as a reference voltage input. When used in reference voltage output, the internal reference voltage Vref is used by the transducer as the reference point for bipolar measurements. The internal reference voltage output accuracy is defined in the electrical parameter data. When used in reference voltage input, an external reference voltage is connected to the REF pin. In this case, the maximun allowable reference voltage range is 0.5 V - 2.75 V. The REF pin must be able to source or sink an input current of 1.5 mA maximum. If the reference voltage is not used, the REF pin should be left unconnected. The following graphs shows the Vref pin current versus forced external Vref. 50 120 40 100 30 80 60 20 40 0 ¦ 2.75 V −10 20 0 ¦ 2.75 V −20 −40 −20 −60 −30 −80 −40 −50 0.5 IPM (A) IPM (A) 10 −100 1 1.5 2 Vref (V) 2.5 3 −120 0.5 1 1.5 2 Vref (V) 2.5 3 Figure 30: Measuring range versus external Vref LESR 6-NP Figure 31: Measuring range versus external Vref LESR 15-NP Upper limit: IP = −9.6 * Vref + 45.6 (Vref = 0.5 … 2.75 V) Lower limit: IP = −9.6 * Vref + 2.4 (Vref = 0.5 … 2.75 V) Upper limit: IP = −24 * Vref + 114 (Vref = 0.5 … 2.75 V) Lower limit: IP = −24 * Vref + 6 (Vref = 0 … 2.75 V) Page 16/20 2August2017/Version 2 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice www.lem.com LESR series External reference voltage 130 200 110 150 90 70 100 50 50 10 ¦ −10 2.75 V IPM (A) IPM (A) 30 −30 2.75 V ¦ 0 −50 −50 −100 −70 −90 −150 −110 −130 0.5 1 1.5 2 Vref (V) 2.5 −200 0.5 3 1 1.5 2 Vref (V) 2.5 3 Figure 32: Measuring range versus external Vref LESR 25-NP Figure 33: Measuring range versus external Vref LESR 50-NP Upper limit: IP = −40 *Vref + 190 (Vref = 1.85 … 2.75 V) Upper limit: IP = 113 (Vref = 0 …1.85 V) Lower limit: IP = −40 * Vref + 10 (Vref = 0 … 2.75 V) Upper limit: IP = 150 (Vref = 0 … 2.75 V) Lower limit: IP = −80 * Vref + 20 (Vref = 0 … 2.125 V) (Vref = 2.125 … 2.75 V) Lower limit: IP = −150 Example with Vref = 1.65 V: ●● The 6 A version has a measuring range from −13.44 A to +29.76 A ●● The 15 A version has a measuring range from −33.6 A to +74.4 A ●● The 25 A version has a measuring range from −56 A to +113 A ●● The 50 A version has a measuring range from −112 A to +150 A Example with Vref = 0.5 V: ●● The 6 A version has a measuring range from −2.4 A to +40.8 A ●● The 15 A version has a measuring range from −6 A to +102 A ●● The 25 A version has a measuring range from −10 A to +113 A ●● The 50 A version has a measuring range from −20 A to +150 A Page 17/20 2August2017/Version 2 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice www.lem.com LESR series PCB footprint 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 No clean process only maximum 260 °C for 10 s Safety This transducer must be used in 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 (e.g. 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. Remark Installation of the transducer must be done unless otherwise specified on the datasheet, according to LEM Transducer Generic Mounting Rules. Please refer to LEM document N°ANE120504 available on our Web site: Products/Product Documentation. Definition of typical, minimum and maximum values 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, maximal and minimal values are determined during the initial characterization of the product. Page 18/20 2August2017/Version 2 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice www.lem.com LESR series Dimensions (in mm) Connection +UC Vout Vref Page 19/20 2August2017/Version 2 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice www.lem.com LESR series Packaging information Standard delivery in cardboard: L × W × H: 315 × 200 × 120 mm Each carboard contains 200 parts, placed into 4 Polystyrene-made trays of 50 parts each one. Both trays and carboard are ESD-compliant. The typical weight of the cardboard is 2.5 Kg. 50 transducers per tray Page 20/20 2August2017/Version 2 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice www.lem.com