Document
Current Transducer LF 305-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
=
300 A
Preliminary
Electrical data
IPN IP RM Primary nominal r.m.s. current Primary current, measuring range Measuring resistance with ± 12 V with ± 15 V with ± 20 V ISN KN VC IC Vd @ ± 300 A max @ ± 500 A max @ ± 300 A max @ ± 500 A max @ ± 300 A max @ ± 500 A max 300 0 .. ± 500 RM min RM max 0 0 0 0 15 15 39 12 58 22 93 45 A A Ω Ω Ω Ω Ω Ω
Features
• Closed loop (compensated) current • Insulated plastic case recognized
according to UL 94-V0. transducer using the Hall effect
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.
Secondary nominal r.m.s. current Conversion ratio Supply voltage (± 5 %) Current consumption R.m.s. voltage for AC isolation test, 50 Hz, 1 mn
150 mA 1 : 2000 ± 12 .. 20 V 16 (@ ± 20 V) + IS mA 3 kV
Accuracy - Dynamic performance data
XG
ε
L
Overall accuracy @ IPN , TA = 25°C Linearity Offset current @ IP = 0, TA = 25°C Residual current 1) @ IP = 0, after an overload of 3 x IPN Thermal drift of IO - 10°C .. + 70°C Reaction time @ 10 % of IPN Response time 2) @ 90 % of IPN di/dt accurately followed Frequency bandwidth (- 1 dB)
± 0.4 < 0.1 Max ± 0.20 ± 0.08 ± 0.1 ± 0.30 < 500 <1 > 100 DC .. 100 Typ
% % mA mA mA ns µs A/µs kHz
Applications
• AC variable speed drives and servo • Static converters for DC motor drives • Battery supplied applications • Uninterruptible Power Supplies • Switched Mode Power Supplies • Power supplies for welding
(SMPS) applications. (UPS) motor drives
IO IOM IOT tra tr di/dt f
General data
TA TS RS m Ambient operating temperature Ambient storage temperature Secondary coil resistance @ TA = 70°C Mass Standards 3) - 10 .. + 70 - 25 .. + 85 28 95 EN 50178 °C °C Ω g
Notes :
1) 2) 3)
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 991125/1
LEM Components
w w w .lem.com
Dimensions LF 305-S
Bottom view
(in mm. 1 mm = 0.0394 inch)
Secondary terminals
Pin + : supply voltage + 12 .. 20 V Pin M : measure Pin - : supply voltage - 12 .. 20 V
Right view
Back view Connection
Top view
Mechanical characteristics
• • • •
General tolerance Fastening Primary through-hole Connection of secondary ± 0.5 mm see drawing ∅ 20 mm Molex 5045-03/AG
Remarks
• IS is positive when IP flows in the direction of the arrow. • Temperature of the primary conductor should not exceed • Dynamic performances (di/dt and response time) are best • This is a standard model. For different versions (supply
voltages, turns ratios, unidirectional measurements...), please contact us. with a single bar completely filling the primary hole. 100°C.
LEM reserves the right to carry out modifications on its transducers, in order to improve them, without previous notice.
.