Selection Guide LLPD


The value of MPFC depends on the distance to the power transformer, which feeds the fault point. Let’s consider an example

6cfff40c463713d463114caf9747df96.png

For this standard case prospective, the fault current is lower than 5 kA  (max LLPD short circuit breaking capability) at 89,7% of the over- headline. It is possible to install the first LLPD 4 km away from the substation.


12dcd8aa02c659b77526a07559e16b40.png

Protection from DLS*

  

Highest voltage for equipment, kV*

12

17.5

24

40.5

52

72.5

MPFC, kA***

<5

<5

<5

<5

<5

<5

LLPD dC10z / dS10z

+

LLPD dC20z

+

+

+

LLPD d24z

+

+

+

LLPD dM35z

+

LLPD d45z

+

LLPD d69z

+


 Protection from IOV*


Highest voltage for equipment, kV*

12

17.5

24

MPFC, kA***

<1.5

<5

<1.5

<5

<1.5

<5

LLPD i20z

+

+

+

LLPD dC10z / dS10z

+

+

LLPD dC20z

+

+

+

+

+

+

LLPD d24z

+

+

+

+

+

+


Note: The above data corresponds to altitude up to 1000 meters

* Basic indications for use LLPD d-series: open areas without natural shielding; hilly, mountainous areas; rivers crossings; sections subjected to frequent lightning strikes; areas with poor accessibility

** According to IEC 60038

*** At the place of LLPD installation. In the case of MPFC is more 5 kA, please check the information below

**** In case the overhead line is located at an altitude of 1000 m  or higher, please check page №13


Please, fill in the form