LA 55-P/SP1

## **Current Transducer LA 55-P/SP1** 

## **I = 50 A** PN 

For the electronic measurement of currents: DC, AC, pulsed..., with galvanic isolation between the primary circuit (high power) and the secondary circuit (electronic circuit). 

16024 

## **Electrical data** 

|**I**PN|Primary nominal current rms|Primary nominal current rms||50|||A|
|---|---|---|---|---|---|---|---|
|**I**PM|Primary current, measuring range|||0 .. ± 100|||A|
|**R**M|Measuring resistance|Measuring resistance|**T**A= 70°C|= 70°C|**T**A= 85°C|||
||||**R**M min **R**M max||**R**M min|**R**M max||
||with ± 12 V|@ ±   50 Amax|0|215|0|210|Ω|
|||@ ± 100 Amax|0|35|0|30|Ω|
||with ± 15 V|@ ±   50 Amax|0|335|30|330|Ω|
|||@ ± 100 Amax|0|95|30|90|Ω|
|**I**SN|Secondary nominal current rms|||25|||mA|
|**K**N|Conversion ratio|||1 : 2000||||
|**V**C|Supply  voltage (± 5 %)|||± 12 .. 15|||V|
|**I**C|Current consumption|||10(@ ± 15 V) + I||(@ ± 15 V) + ISmA|mA|



## **Accuracy - Dynamic performance data** 

## **Features** 

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

- Printed circuit board mounting 

- Insulated plastic case recognized according to UL 94-V0. 

## **Special features** 

- **I** PM = 0 .. ± 100 A 

- ● **K** N = 1 : 2000. 

## **Advantages** 

- Excellent accuracy 

|**X**|Accuracy @**I**PN,**T**A= 25°C|@ ± 15 V (± 5 %)|@ ± 15 V (± 5 %)|@ ± 15 V (± 5 %)|± 0.65|± 0.65|%|
|---|---|---|---|---|---|---|---|
||@ ± 12 .. 15 V (± 5 %)|@ ± 12 .. 15 V (± 5 %)||@ ± 12 .. 15 V (± 5 %)|± 0.90|± 0.90|%|
|εL|Linearity error||||< 0.15|< 0.15|%|
||||||Typ|Max||
|**I**O<br>**I**OM|Offset current @**I**P= 0,**T**A= 25°C<br>Magnetic offset current1)@**I**P= 0 and specified||= 25°C<br>= 0 and specified**R**M,|||± 0.10|mA|
||after an overload of 3 x**I**PN|||||± 0.15|mA|
|**I**OT|Temperature variation of**I**O|- 25°C .. + 85°C|||± 0.05 ± 0.30|± 0.05 ± 0.30|mA|
||||- 40°C .. - 25°C||± 0.10 ± 0.50|± 0.10 ± 0.50|mA|
|**t**ra|Reaction time to 10 % of**I**PNstep||||< 500|< 500|ns|
|**t**r|Response time2)to 90 % of**I**PNstep|||step|< 1||µs|
|**di/dt**|di/dt accurately followed||||> 200|> 200|A/µs|
|**BW**|Frequency bandwidth (- 1 dB)||||DC .. 200||kHz|
|**General data**||||||||
|**T**A|Ambient operating temperature|Ambient operating temperature|||- 40 .. + 85||°C|
|**T**S|Ambient storage temperature||||- 40 .. + 90||°C|
|**R**S|Secondary coil resistance|||@**T**A= 70°C|145||Ω|
|||||@**T**A= 85°C|150||Ω|
|**_m_**|Mass||||18||g|
||Standards||||EN 50178: 1997|||



- 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** 

Notes:[1)] Result of the coercive field of the magnetic circuit 2)  With a di/dt of 100 A/µs. 

- Industrial. 

Page 1/3 

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

090519/13 

www.lem.com 

**Current Transducer LA 55-P/SP1** 

## **Isolation characteristics** 

|**V**d|Rms voltage for AC isolation test, 50 Hz, 1 min|2.5|kV|
|---|---|---|---|
|**V**w|Impulse withstand voltage 1.2/50 µs|4.5|kV|
|||Min||
|**dCp**|Creepage distance|3.8|mm|
|**dCI**|Clearance distance|3.8|mm|
|**CTI**|Comparative Tracking Index (group IIIa)|175||



## **Applications examples** 

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

- Over voltage category OV 3 

- Pollution degree PD2 

- 

- Non-uniform field 

|Pollution degree PD2<br>Non-uniform feld|||
|---|---|---|
||**EN 50178**|**IEC 61010-1**|
|**dCp**,**dCI**,<br>**V**w|Rated isolation voltage|Nominal voltage|
|Single isolation|300 V|300 V|
|Reinforced isolation|150 V|150 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 

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

090519/13 

www.lem.com 

## **Dimensions LA 55-P/SP1** (in mm. 1 mm = 0.0394 inch) 

**==> picture [492 x 328] intentionally omitted <==**

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


## **Mechanical characteristics** 

- General tolerance ± 0.2 mm 

- ● Primary through-hole 12.7 x 7 mm ● Fastening & connection of secondary 3 pins 0.63 x 0.56 mm 

- ● Recommended PCB hole 0.9 mm 

## **Remarks** 

- **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 single bar completely filling the primary hole. 

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

Page 3/3 

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

090519/13 

www.lem.com