LTC 350-SF

## **Current Transducer LTC 350-SF** 

## _I_ **= 350 A** P N 

For the electronic measurement of currents: DC, AC, pulsed..., with galvanic separation between the primary circuit and the secondary circuit. 

## ~~**Electrical data**~~ 

||~~**Electrical data**~~|||||
|---|---|---|---|---|---|
|_I_P N|Primary nominal RMS current||350||A|
|_I_P M|Primary current, measuring range|@ ±24 V|0 ... ±1200||A|
|_R_M|Measuring resistance||_R_M min|_R_M max||
||with ±15 V<br>@ ±500|Amax|0|30|Ω|
||@ ±900|Amax|0|8|Ω|
||with ±24 V<br>@ ±500|Amax|10|60|Ω|
||@ ±1200 Amax||10|17|Ω|
|_I_S N|Secondary nominal RMS current||175||mA|
|_N_P/_N_STurns ratio|||1 : 2000|||
|_U_C|Supply voltage (±5 %)||±15 ...|24|V|
|_I_C|Current consumption||< 35(@ ±24 V)+_I_S||mA|
||~~**Accuracy - Dynamic performance data**~~|||||
|_ε_tot|Total error @_I_P N,_T_A= 25 °C||< ±0.5||%|
|_ε_L|Linearity error||< 0.1||%|
||||Max|||
|_I_O|Ofset current @_I_P= 0,_T_A= 25 °C||±0.5||mA|
|_I_O_T_|Temperature variation of_I_O|−40 °C ... +85 °C|±0.8||mA|
|_t_D 90|Delay time to 90 % of the fnal output value for_I_P Nstep||1)< 1||µs|
|_BW_|Frequency bandwidth (−1 dB)||DC ... 100||kHz|
||~~**General data**~~|||||
|_T_A|Ambient operating temperature||−40 ...|+85|°C|
|_T_A st|Ambient storage temperature||−45 ...|+90|°C|
|_R_S|Resistance of secondary winding @_T_A= 85 °C||15||Ω|
|_m_|Mass||400||g|
||Standards||EN 50155: 2021||2)|
||||EN 50121-3-2: 2016|||



## **Features** 

- ●Closed loop (compensated) current transducer using the Hall effect 

- ●Insulating plastic case recognized 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 

- ●Current overload capability. 

## **Applications** 

- ●Single or three phase inverters 

- ●Propulsion and braking choppers 

- ●Propulsion converters 

- ●Auxiliary converters 

- ●Battery chargers. 

## **Application Domain** 

- ●Railway (fixed installations and onboard). 

Notes:[1)] For a d _i_ /d _t_ = 100 A/µs 

- 2) Additional information available on request. 

N° 97.A2.47.000.0 

Page 1/3 LEM International SA Route du Nant-d’Avril, 152 1217 Meyrin www.lem.com 

LEM reserves the right to carry out modifications on its transducers, in order to improve them. 

15July2024/Version 7 

## **Current Transducer LTC 350-SF** 

## ~~**Insulation coordination**~~ 

**==> picture [333 x 111] intentionally omitted <==**

**----- Start of picture text -----**<br>
U d RMS voltage for AC insulation test, 50 Hz, 1 min  12  [1)] kV<br>1.5  [2)] kV<br>Min<br>d Cp Creepage distance  50  mm<br>d CI Clearance  44  mm<br>CTI Comparative tracking index (group I)  600<br>Notes: [1)]  Between primary and secondary + shield<br>2) Between secondary and shield.<br>**----- End of picture text -----**<br>


## **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 (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 LEM International SA Route du Nant-d’Avril, 152 1217 Meyrin www.lem.com 

LEM reserves the right to carry out modifications on its transducers, in order to improve them. 

15July2024/Version 7 

## **Dimensions LTC 350-SF** (in mm) 

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**----- Start of picture text -----**<br>
Connection<br>I<br>I P S R M<br>U C<br>U C<br>d cl d cp<br>**----- End of picture text -----**<br>


## **Mechanical characteristics** 

- ●General tolerance 

- ●Transducer fastening 

- ●Primary through-hole 

- ●Connection of secondary 

±1 mm 

4 slots ⌀ 5.5 mm 

4 M5 steel screws 

⌀ 27.5 mm 

4 M5 threaded studs 

- Faston 6.3 × 0.8 mm 

## **Remarks** 

- _I_ S is positive when _I_ P flows in the direction of the arrow. 

- ●Temperature of the primary conductor should not exceed 100 °C. 

- ●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: **https://www.lem.com/en/file/3137/download/.** 

- ●Dynamic performances ( d _i_ /d _t_ and delay 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. 

Page 3/3 LEM International SA Route du Nant-d’Avril, 152 1217 Meyrin www.lem.com 

LEM reserves the right to carry out modifications on its transducers, in order to improve them. 

15July2024/Version 7