LA 125-P

## **Current Transducer LA 125-P** 

## **I = PN** 

## **125 A** 

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). 

## 2002/95/EC 16030 

## **Electrical data** 

**I** PN Primary nominal current rms 125 A **I** PM Primary current, measuring range 0 .. ± 200 A **R** M Measuring resistance @ **T** A = 70°C **T** A = 85°C **R R R R** M mini M maxi M mini M maxi with ± 12 V @ ± 125 A maxi 5 52 14 50 Ω @ ± 200 A maxi 5 20 14 18 Ω with ± 15 V @ ± 125 A maxi 25 74 40 72 Ω @ ± 200 A maxi 25 34 40[ 1)] 40[ 1)] Ω **I** SN Secondary nominal current rms 125 mA **K** N Conversion ratio 1 : 1000 **V** C Supply  voltage (± 5 %) ± 12 .. 15 V **I** C Current consumption 16 (@ ± 15 V) + **I** S mA 

## **Accuracy - Dynamic performance data** 

**X** Accuracy @ **I** PN , **T** A = 25°C @ ± 15 V (± 5 %) ± 0.60 % @ ± 12 .. 15 V (± 5 %) ± 0.80 % **ε** L Linearity error < 0.15 % Typ Maxi **I** O Offset current @ **I** P = 0, **T** A = 25°C ± 0.40 mA **I** OM Magnetic offset current[ 2) ] @ **I** P = 0 and specified **R** M, after an overload of 3 x **I** PN ± 0.50 mA **I** OT Temperature variation of **I** O 0°C .. + 70°C ± 0.15 ± 0.50 mA - 40°C .. + 85°C ± 0.30 ± 0.95 mA **t** ra Reaction time @ 10 % of **I** PN < 500 ns **t** r Response time[ 3) 4)] to 90 % of **I** PN step < 1 µs **di/dt** di/dt accurately followed[ 4)] > 200 A/µs **BW** Frequency bandwidth[ 4)] (- 1 dB) DC .. 100 kHz **General data T** A Ambient operating temperature - 40 .. + 85 °C **T** S Ambient storage temperature - 40 .. + 90 °C **R** S Secondary coil resistance @ **T** A = 70°C 32 Ω **T** A = 85°C 33.5 Ω _**m**_ Mass 40 g Standards EN 50178: 1997 

## **Features** 

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

- Printed circuit board mounting 

- Isolated 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** 

- 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 Domain** 

      - Industrial. 

- Notes: 1) Measuring range limited to ± 180 A maxi 

   - 2) The result of the coercive field of the magnetic circuit. 

   - 3) With a di/dt of 100 A/µs 

   - 4) The primary conductor is best filling the through-hole and/or the return of the primary conductor is above the top of the transducer. 

page 1/3 

070806/12 

www .lem.com 

LEM  reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice. 

## **Current Transducer LA 125-P** 

## CT **Isolation characteristics** 

|**V**d|Rms voltage for AC isolation test, 50/60 Hz, 1 min|3|kV|
|---|---|---|---|
|**V**w|Impulse withstand voltage 1.2/50 µs|7|kV|
|||Mini||
|**dCp**|Creepage distance|6.7|m m|
|**dCl**|Clearance distance|6.7|m m|
|**CTI**|Comparative Tracking Index  (Group IIIa)|175||



## **Application examples** 

**According to EN 50178 and IEC 61010-1 standards** and following conditions: 

- Over voltage category OV 3 

- Pollution degree PD2 

• Non-uniform field 

|• Over voltage category OV 3<br>• Pollution degree PD2<br>• Non-uniform field|Over voltage category OV 3<br>~~ee~~|~~ee~~|
|---|---|---|
||**EN 50178**<br>~~ee~~<br>~~es~~|**IEC 61010-1**<br>~~ee~~|
|dCp, dCI,<br>**VW**<br>~~ee~~|Rated isolation voltage<br>~~ee~~<br>~~ee~~<br>~~es~~|Nominal voltage<br>~~ee~~<br>~~ee~~|
|Single isolation|600 V<br>~~es~~<br>~~es~~|600 V|
|Reinforced isolation<br>~~ee~~|300 V<br>~~ee~~<br>~~es~~|300 V<br>~~ee~~|



## **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 built-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 

070806/12 

www .lem.com 

LEM  reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice. 

**==> picture [136 x 36] intentionally omitted <==**

**==> picture [33 x 33] intentionally omitted <==**

## **Dimensions  LA 125-P** (in mm. 1 mm = 0.0394 inch) 

**==> picture [511 x 387] intentionally omitted <==**

**----- Start of picture text -----**<br>
Bottom view Left view<br>Connection<br>Front view<br>**----- End of picture text -----**<br>


## **Mechanical characteristics** 

## **Remarks** 

- General tolerance 

   - ± 0.2 mm 17 x 11 mm 

- Primary through-hole 

- Fastening & connection of secondary 4 pins 0.63 x 0.56 mm Recommended PCB hole 0.9 mm 

- Supplementary fastening 2 holes ∅ 1.75 mm Recommended PCB hole 2.4 mm Recommended screws PT KA  22 x 6 Recommended fastening torque 0.5 Nm or .37 Lb. - Ft. 

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

- Temperature of the primary conductor should not exceed 90°C. 

- Dynamic performances (di/dt and response time) are best with a primary bar in low position in the through-hole. 

- In order to achieve the best magnetic coupling, the primary windings have to be wound over the top edge of the device. 

- This is a standard model. For different versions (supply voltages, turns ratios, unidirectional measurements...), please contact us. 

page 3/3 

070806/12 

www .lem.com 

LEM  reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice.