CKSR 75-NP

Current Transducer CKSR 75-NP IP N = 75 A Ref: CKSR 75-NP For the electronic measurement of current: DC, AC, pulsed…, with galvanic separation between the primary and the secondary circuit. Features Applications ●● Closed loop (compensated) multi-range ●● AC variable speed and servo motor drives current transducer ●● Static converters for DC motor drives ●● Voltage output ●● Battery supplied applications ●● Single supply ●● Uninterruptible Power Supplies (UPS) ●● Compact design for PCB mounting. ●● Switched Mode Power Supplies (SMPS) ●● Power supplies for welding applications Special feature ●● Dedicated 5 primary conductors configuration. Advantages ●● Very low temperature coefficient of offset ●● Very good dv/dt immunity ●● Reduced height ●● Reference pin with two modes: Ref IN and Ref OUT ●● Extended measuring range for unipolar measurement. ●● Solar inverters. Standards ●● IEC 60950-1: 2006 ●● IEC 61010-1: 2010 ●● IEC 61326-1: 2012 ●● UL 508: 2010. Application Domain ●● Industrial. N°52.E7.30.000.0 5September2018/version 1 Page 1/12 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice LEM International SA Chemin des Aulx 8 1228 PLAN-LES-OUATES Switzerland www.lem.com  CKSR 75-NP 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 × IP N UESD max kV 4 Maximum ESD rating, Human Body Model (HBM) 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 ●● UL 508 STANDARD FOR INDUSTRIAL CONTROL EQUIPMENT - Edition 17 Ratings Parameter Symbol Primary involved potential Unit Value V AC/DC 1000 Max surrounding air temperature TA °C 105 Primary current IP A 75 Secondary supply voltage UC V DC 5 Output voltage Uout 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. Page 2/12 5September2018/version 1 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice LEM International SA Chemin des Aulx 8 1228 PLAN-LES-OUATES Switzerland www.lem.com  CKSR 75-NP Insulation coordination Parameter Symbol Unit Value RMS voltage for AC insulation test, 50 Hz, 1 min Ud kV 4.1 According to UL 94 Impulse withstand voltage 1.2/50 µs UNi kV 7.5 According to UL 94 Partial discharge extinction RMS voltage @ 10 pC Ue V 1000 According to UL 94 Clearance (pri. - sec.) dCI mm 7.5 Shortest internal distance through air 1) Creepage distance (pri. - sec.) dCp mm 7.5 Shortest internal path along device body 1) Clearance (pri. - sec.) dCI mm 6.1 When mounted on PCB with recommended layout Creepage distance (pri. - sec.) dCp mm 6.1 When mounted on PCB with recommended layout - - V0 According to UL 94 Case material Comment Comparative tracking index CTI 600 Application example RMS voltage line-to-neutral - V 300 Reinforced insulation, according to IEC 61010-1 CAT III PD2 Application example RMS voltage line-to-neutral - V 600 Basic insulation, according to IEC 61010-1 CAT III PD2 Symbol Unit Min Ambient operating temperature TA °C −40 105 Ambient storage temperature TS °C −55 105 Mass m g Note: 1) Inside device enclosure providing protection IP5x. Environmental and mechanical characteristics Parameter Note: 1) Typ Max Comment 1) 9 The working conditions have direct impact on the temperature of primary conductor. In any cases, the temperature of conductor must be below 110 °C according to absolute maximum ratings in page 2. Page 3/12 5September2018/version 1 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice LEM International SA Chemin des Aulx 8 1228 PLAN-LES-OUATES Switzerland www.lem.com  Electrical data CKSR 75-NP At TA = 25 °C, UC = +5 V, NP = 1 turn, RL = 10 kΩ, internal reference unless otherwise noted (see definition of typ, Min, Max. paragraph in page 8). Parameter Symbol Unit Primary nominal RMS current IP N A Primary current, measuring range IP M A Primary current, measuring range IP M Min Typ Max Comment Apply derating according to Figure 1. 75 −180 A −182 4.75 180 With UC = 4.75 V, TA = 85 °C, RL = 10 kΩ. For other conditions, see Figure 7. 182 Number of primary turns NP Supply voltage UC V Current consumption IC mA Reference voltage @ IP = 0 A Uref V 2.495 External reference voltage UE ref V 0 4 Output voltage Uout V Uref−1.125 Uref+1.125 Output voltage @ IP = 0 A Uout V Electrical offset voltage UO E mV −0.725 0.725 100 % tested Uout − Uref Electrical offset current referred to primary IO E mA −116 116 100 % tested Temperature coefficient of Uref TCUref ppm/K ±50 Internal reference Temperature coefficient of Uout @ IP = 0 A TCUout ppm/K ±4 ppm/K of 2.5 V −40 °C … 105 °C (at ±6 Sigma) Nominal sensitivity SN mV/A Sensitivity error εS % −0.7 0.7 100 % tested TCS ppm/K −40 40 −40 °C … 105 °C εL % of IP N −0.1 0.1 Magnetic offset current (10 × IP N) referred to primary IO M A −0.1 0.1 RMS noise current (spectral density) 100 Hz … 100 kHz referred to primary Ino µA/Hz½ - mV 10 RL = 1 kΩ Delay time @ 10 % of IP N tD 10 µs 0.3 RL = 1 kΩ, di/dt = 68 A/ µs Delay time to 90 % of IP N tD 90 µs 0.3 RL = 1 kΩ, di/dt = 68 A/ µs Frequency bandwidth (±1 dB) BW kHz 200 RL = 1 kΩ Frequency bandwidth (±3 dB) BW kHz 300 RL = 1 kΩ Total error εtot % of IP N 1.2 εtot % of IP N 1.6 Error ε % of IP N 1 Error @ TA = 105 °C ε % of IP N 1.4 Temperature coefficient of S Linearity error Peak-peak output ripple at oscillator frequency f = 450 kHz (typ.) Total error @ TA = 105 °C 5September2018/version 1 1,2,3,4,5 5 15 + 5.25 I (mA) IP (mA) 20 + P NS = 966 turns NS NS 2.5 2.505 Internal reference @ IP M Uref ±5 6.25 468.5 mV/IP N 20 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice RL = 1 kΩ Page 4/12 LEM International SA Chemin des Aulx 8 1228 PLAN-LES-OUATES Switzerland www.lem.com  CKSR 75-NP Maximum continuous DC primary current 160 140 120 Ip(A) 100 80 60 40 20 0 0 20 40 60 80 100 120 TA (℃) Figure 1: IP vs TA for CKSR 75-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 ●● Resistor power dissipation < 0.5 × rated power Frequency derating AC Derating max RMS AC current / max DC current 1.25 1 0.75 0.5 0.25 0 10 100 1k 10k 100k 1M f (Hz) Figure 2: Maximum RMS AC primary current / maximum DC primary current vs frequency Page 5/12 5September2018/version 1 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice LEM International SA Chemin des Aulx 8 1228 PLAN-LES-OUATES Switzerland www.lem.com  CKSR 75-NP Terms and definitions Ampere-turns and amperes The transducer is sensitive to the primary current linkage ΘP (also called ampere-turns). ΘP = NP ⋅ IP 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 (A) unit is used to emphasis that current linkages are intended and applicable. 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 S 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. Simplified transducer model The static model of the transducer with current output at temperature TA is: Is = S ⋅ ΘP ⋅ (1 + ε) In which (referred to primary): ε ⋅ ΘP = IO E + IO T + εS⋅ ΘP + εS T ⋅ ΘP + εL(ΘP max) ⋅ ΘP max + IO M With: ΘP = NP ⋅ IP : primary current linage (A) ΘP max : maximum primary current linkage applied to the transduer IS : secondary current (A) S : sensitivity of the transducer TA : ambient operating temperature (°C) IO E : electrical offset current (A) IO M : magnetic offset current (A) IO T : temperature variation of IO E (A) εS : sensitivity error at 25 °C εS t : thermal drift of S εL(ΘP max) : linearity error for ΘP max This model is valid for primary ampere-turns ΘP between −ΘP max and +ΘP max only. This is the absolute maximum error. As all errors are independent, a more realistic way to calculate the error would be to use the following formula: ε= N ∑εi 2 i=1 Page 6/12 5September2018/version 1 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice LEM International SA Chemin des Aulx 8 1228 PLAN-LES-OUATES Switzerland www.lem.com  Performance parameters definition CKSR 75-NP Magnetic offset referred to primary Delay times 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 IP ≥ IP N. The delay time tD 10 @ 10 % and the delay time tD 90 @ 90 % with respect to the primary are shown in the next figure. Both slightly depend on the primary current di/dt. They are measured at nominal current. I Primary current cycle 100 % with KOL = 1 .. 10 IP / (KOL · IP N) 1 90 % IS IP tD 90 0 -1 10 % t tD 10 1 2 3 4 5 Step KOL: Overload factor Figure 3: Current cycle used to measure magnetic and electrical offset (transducer supplied) IP (3) − IP (5) IO M = 2 Figure 5: tD 10 (delay time @ 10 %) and tD 90 (delay time @ 90 %). Total error referred to primary The total error εtot is the error at ±IP N, relative to the rated value IP N. It includes all errors mentioned above ●● the electrical offset IO E Electrical offset referred to primary ●● the magnetic offset IO M Using the current cycle shown in figure 3, the electrical offset current IO E is the residual output referred to primary when the input current is zero. ●● the linearity error εL (to IP N). IP (3) + IP (5) 0.12 2 0.10 The temperature variation IO T of the electrical offset current IO E is the variation of the electrical offset from 25 °C to the considered temperature. I O T (T ) = I O E (T ) − I O E ( 25 °C ) Note: the transducer has to be demagnetized prior to the application of the current cycle (for example with a demagnetization tunnel). UC RM Total error ℇtot at UC = ... V and TA = 25 °C aver. + 3σ 0.08 ℇtot (% IP N) IO E = ●● the sensitivity error εS IO M (max) / IP N 0.06 = 0.04 IO E (max) / IP N 0.02 0.00 -0.02 -1 -0.5 0 0.5 IP / (KOL · IP N) with KOL = 1 ... 10 1 Figure 6: Total error εtot Uout Uref Figure 4: Test connection Page 7/12 5September2018/version 1 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice LEM International SA Chemin des Aulx 8 1228 PLAN-LES-OUATES Switzerland www.lem.com  CKSR 75-NP Performance parameters definition (continued) 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 8/12 5September2018/version 1 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice LEM International SA Chemin des Aulx 8 1228 PLAN-LES-OUATES Switzerland www.lem.com  CKSR 75-NP Application information Filtering and decoupling Reference Uref Supply voltage UC The fluxgate oscillator draws current pulses of up to 30 mA at a rate of ca. 900 kHz. Significant 900 kHz voltage ripple on UC 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 Uout and reference Uref. 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). 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. Output Uout The output Uout 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 Uout is 1 kOhm. 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 of primary turns Primary resistance RP [mΩ] 1 0.144 2 5 Recommended connections 10 9 8 7 6 out in 1 10 2 9 3 8 4 7 5 6 out in 1 10 2 9 3 8 4 7 5 6 in 1 2 3 4 5 0.6 out 3.6 Measurement range 250 Max current(A) 230 210 With Uc=4.75V 190 With Uc=5V With Uc=5.25V 170 -40 -20 150 0 20 40 60 80 100 120 Ambient Temperature(℃) Figure 7: The measurement range vs. temperature Page 9/12 5September2018/version 1 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice LEM International SA Chemin des Aulx 8 1228 PLAN-LES-OUATES Switzerland www.lem.com  CKSR 75-NP 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 Uref”. 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 Uref must be able: - either to source a typical current of - or to sink a typical current of U ref − 2.5 , the maximum value will be 2.2 mA typ. when Uref = 4 V. 680 2.5 − U ref , the maximum value will be 3.68 mA typ. when Uref = 0 V. 680 Page 10/12 5September2018/version 1 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice LEM International SA Chemin des Aulx 8 1228 PLAN-LES-OUATES Switzerland www.lem.com  CKSR 75-NP PCB footprint R Assembly on PCB ●● Recommended PCB hole diameter ●● Maximum PCB thickness ●● Wave soldering profile 1.3 mm for primary pin 0.8 mm for secondary pin 2.4 mm maximum 260 °C for 10 s No clean process only Safety This transducer must be used in limited-energy secondary circuits according to IEC 61010-1. d d 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. Cl Cp 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. Page 11/12 5September2018/version 1 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice LEM International SA Chemin des Aulx 8 1228 PLAN-LES-OUATES Switzerland www.lem.com  CKSR 75-NP Dimensions (in mm, general linear tolerance ±0.25 mm) Connection UC RM Uout Uref dCl RM dCp dCp dCl dCp Page 12/12 5September2018/version 1 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice LEM International SA Chemin des Aulx 8 1228 PLAN-LES-OUATES Switzerland www.lem.com