Three phase earthing device for MV overhead lines – application from the ground

Three phase earthing device for MV overhead lines – application from the ground


Category:

   

Code: Msp – CAA – AS – 3xSp/lp – O/p  

 The three phase earthing device provided with automatic self-locking phase clamps (CAA) can be applied from the ground on MV overhead lines, up to 9 m height.

The main parts of the phase clamp are made by casting from aluminium alloy. This clamp (CAA) is provided with a special coupling system for setting up on conductor and a steel ring for removal from conductor. The new coupling system allows easy and safe mounting of the clamp on the applicator. This system avoid an accidental detachment of the clamp and assures a simultaneously detachment of the clamp from the applicator along with its fastening on conductor.

The operation should be performed from the ground using a long telescopic insulating stick (maximum length 9 meters, code: PTU-AS-400kV-6-C). Before the setting up of the CAA clamp, a special applicator must be fixed on the bayonet coupling system of the stick, then the phase clamp must be attached to this applicator. The fastening of the phase clamp on conductor is performed by hooking and pulling downward of the clamp. The removal of the phase clamp could be performed by hooking and pulling downward the steel ring of the phase clamp. At the removal operation, an insulating stick with removal hook should be used.

Attention! It is recommended that the cross-sections of the cables do not exceed 50 mm² (due to the heavy weight of the cables, the setting up procedure will be difficult to be performed).

Technical characteristics

Earthing cable section S(mm2)

16

25

35

50

70

Nominal short-circuiting current for t = 1 s Isc (kA)

4

6

8

12

16

Nominal peak currrent for t = 0,02 s Isd (kA)

10

15

20

30

40

Testing short-circuiting current for t = 1s Itest (kA)

4,6

6,9

9,2

13,8

18,4

Testing peak current for t = 0,02 s Ipeak (kA)

11,5

17,25

23

34,5

46

Peak factor (SR EN 61230)

2,5

Earthing cable length l(m)

max. 15

Conductor diameter on which the clamp can be applied (mm)

5÷32

6÷32

 This equipment contains the following components:
– Automatic self-locking phase clamps (CAA) – 3 pieces
– Earthing cables – 3 pieces
– Earthing clamp – 1 piece
– Earthing rod – 1 piece
– Clamp applicator – 1 piece
– Removal hook – 1 piece

This equipment is delivered in a carrying bag or a transport case.