Current Transducer LF 305-S For the electronic measurement of currents: DC, AC, pulsed..., with galvanic isolation between the primary circuit (high power) and the secondary circuit (electronic circuit). 16167 Features Electrical data IPN Primary nominal current rms IPM Primary current, measuring range R M Measuring resistance @ with ± 12 V @ ± 300 A max @ ± 500 A max with ± 15 V @ ± 300 A max @ ± 500 A max with ± 20 V @ ± 300 A max @ ± 500 A max ISN Secondary nominal current rms K N Conversion ratio VC Supply voltage (± 5 %) IC Current consumption 300 A 0 .. ± 500 A TA = 70°C TA = 85°C RM minRM max RM minRM max 0 37 0 35 Ω 0 10 0 8 Ω 0 56 0 54 Ω 0 21 0 19 Ω 0 88 0 86 Ω 0 40 0 38 Ω 150 mA 1 : 2000 ± 12 .. 20 V 26 (@± 20V)+ IS mA Overall accuracy @ IPN , TA = 25°C ± 0.5 Linearity error < 0.1 Typ Max Offset current @ IP = 0, TA = 25°C ± 0.2 Magnetic offset current 1) @ IP=0 and specified RM after an overload of 3 x IPN ± 0.2 Temperature variation of IO - 40°C .. + 85°C ± 0.2 ± 0.7 - 10°C .. + 70°C ± 0.1 ± 0.3 Reaction time to 10 % of IPN < 500 Response time 2) to 90 % of IPN step < 1 di/dt accurately followed > 100 Frequency bandwidth (- 1 dB) DC .. 100 % % mA mA mA mA ns µs A/µs kHz Advantages ●● ●● ●● ●● ●● ●● ●● Excellent accuracy Very good linearity Low temperature drift Optimized response time Wide frequency bandwidth No insertion losses High immunity to external interference ●● Current overload capability. ●● AC variable speed drives 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. Application domains ●● Industrial. General data TA TS RS m ●● Closed loop (compensated) current transducer using the Hall effect ●● Isolated plastic case recognized according to UL 94-V0. Applications Accuracy - Dynamic performance data XG εL IO IOM IOT tra tr di/dt BW IPN = 300 A Ambient operating temperature Ambient storage temperature Secondary coil resistance @ TA = 70°C TA = 85°C Mass Standards - 40 .. + 85 - 40 .. + 85 30 32 95 EN 50178:1997 °C °C Ω Ω g Notes:1) The result of the coercive field of the magnetic circuit 2) With a di/dt of 100 A/µs. 110210/11 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice. Page 1/3 www.lem.com Current Transducer LF 305-S Isolation characteristics Vd Vw dCp dCI CTI Rms voltage for AC isolation test, 50 Hz, 1 min Impulse withstand voltage 1.2/50 µs Creepage distance Clearance distance Comparative Tracking Index (group IIIa) 3.8 10 Min 11.9 11.5 175 kV kV mm mm Applications examples According to EN 50178 and IEC 61010-1 standards and following conditions: ●● Over voltage category OV 2 ●● Pollution degree PD2 ●● Non-uniform field dCp, dCI, Vw EN 50178 IEC 61010-1 Rated insulation voltage Nominal voltage Basic insulation 1000 V 1000 V Reinforced insulation 500 V 500 V Safety 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. Page 2/3 110210/11 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice. www.lem.com Dimensions LF 305-S (in mm.) Connection Mechanical characteristics Remarks ●● General tolerance ± 0.5 mm ●● Transducer fastening Vertical position 2 holes Ø 4.3 mm 2 M4 steel screws Recommended fastening torque 3.2 Nm or 4 holes Ø 1.9 mm, depth: 7 mm 4 PTKA 25 screws length: 6 mm Recommended fastening torque 0.7 Nm ●● Transducer fastening Horizontal position 4 holes Ø 4.3 mm 4 M4 steel screws Recommended fastening torque 3.2 Nm or 4 holes Ø 1.9 mm crossing 4 PTKA 25 screws, length: 10 mm Recommended fastening torque 0.75 Nm ●● Primary through-hole Ø 20.1 mm ●● Connection of secondary Molex 6410 3 Tin plated pins ●● IS is positive when IP flows in the direction of the arrow. ●● Temperature of the primary conductor should not exceed 100°C. ●● Dynamic performances (di/dt and response time) are best with a single bar completely filling the primary hole. ●● This is a standard model. For different versions (supply voltage, turns ratios, unidirectional measurements ...), please contact us. 110210/11 LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice. Page 3/3 www.lem.com