LA255-S

Current Transducer LA 255-S For the electronic measurement of currents : DC, AC, pulsed..., with a galvanic isolation between the primary circuit (high power) and the secondary circuit (electronic circuit). IPN = 250 A Electrical data IPN IP ÎP max RM Primary nominal r.m.s. current Primary current, measuring range Measuring overload 1) Measuring resistance @ with ± 12 V with ± 15 V with ± 18 V ISN KN VC IC Vb @ ± 250 A max @ ± 500 A max @ ± 250 A max @ ± 500 A max @ ± 250 A max @ ± 500 A max 250 0 .. ± 500 600 TA = 70°C TA = 85°C RM min RM max RM min RM max 0 0 5 5 25 25 49 7 70 17 93 29 0 0 5 5 25 25 47 5 68 15 91 27 A A A Features •Closed loop (compensated) current transducer using the Hall effect •Insulated plastic case recognized Ω Ω Ω Ω Ω Ω according to UL 94-V0. Advantages •Excellent accuracy •Very good linearity •Low temperature drift •Optimized response time •Wide frequency bandwidth •No insertion losses •High immunity to external interference Secondary nominal r.m.s. current Conversion ratio Supply voltage (± 5 %) Current consumption R.m.s. rated voltage 2), safe separation basic isolation 125 mA 1 : 2000 ± 12 .. 18 V 20 (@ ± 15 V) + IS mA 1625 V 3250 V •Current overload capability. Accuracy - Dynamic performance data XG ε L Overall accuracy @ IPN , TA = 25°C Linearity Offset current @ IP = 0, TA = 25°C Residual current 3) @ IP = 0, after an overload of 3 x IPN Thermal drift of IO - 10°C .. + 85°C Reaction time @ 10 % of IP max Response time 4) @ 90 % of IP max di/dt accurately followed Frequency bandwidth (- 3 dB) Ambient operating temperature Ambient storage temperature Secondary coil resistance @ Mass Standards 1) 2) ± 0.8 < 0.1 Max ± 0.15 ± 0.50 ± 0.15 ± 0.30 < 500 100 DC .. 100 - 10 .. + 85 - 40 .. + 90 35 37 110 EN 50178 Typ % % mA mA mA ns µs A/µs kHz °C °C Ω Ω g Applications •AC variable speed drives and servo motor drives IO IOM IOT tra tr di/dt f TA TS RS m Notes : •Static converters for DC motor drives •Battery supplied applications •Uninterruptible Power Supplies (UPS) •Switched Mode Power Supplies (SMPS) •Power supplies for welding applications. General data TA = 70°C TA = 85°C 5) 3) 4) 5) 3 mn/hour @ VC = ± 15 V, R M = 5 Ω Pollution class 2. With a non insulated primary bar which fills the through-hole The result of the coercive field of the magnetic circuit With a di/dt of 100 A/µs A list of corresponding tests is available 980707/3 LEM Components w w w .lem.com Dimensions LA 255-S Front view (in mm. 1 mm = 0.0394 inch) Left view Secondary terminals Terminal + : supply voltage + 12 .. 18 V Terminal M : measure Terminal - : supply voltage - 12 .. 18 V Connection Top view Mechanical characteristics •General tolerance •Fastening •Primary through-hole •Connection of secondary ± 0.5 mm 2 holes ∅ 5.5 mm 23 x 18 mm Faston 6.3 x 0.8 mm Remarks •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 voltages, turns ratios, unidirectional measurements...), please contact us. LEM reserves the right to carry out modifications on its transducers, in order to improve them, without previous notice.