■An overview of the

Clearance outside the lightning arrester is a coastal city, industrial city, frequent fog, air humidity and large heavy air pollution area design and development of aerial power cable insulation lightning protection device.

■Principle and characteristics of

Penetrating clearance outside the arrester is suitable for the distribution of 10kv overhead insulated conductor, the adopted patent involve penetrating arc structure, can penetrate the material form the electrical connection in the wires; Arc head bottom as opposed to a lightning arrester in the arc at the top of the head, forming a span of 60 ~ 130 mm series outside the gap, the distance through the lower part of arrester relative movement of the two pieces of mounting plate to adjust. Under the normal condition, high resistance of arrester resistors and discharge gap action; Only in excess of the prescribed lightning overvoltage appeared first, breakdown, discharge gap can be formed short- -circuit channels, in place of the power frequency arc outer gap between combustion and overvoltage energy released, in order to protect the wires from being burned. Voltage is released, lighting arrester resistors to recover high resistance discharge gap to stop.

■Technical parameters and the selection table

■Lightning arrester consists of two parts

The first part:

1) aluminum alloy piercing power cable.

2) set in the aluminum alloy power cable puncture in vitro of the silicone rubber protective cover.

The second part:

1) high resistance arrester resistor + silica gel coat.

2) and the transverse connection accessories.

■Important notes

1) High resistance ac power frequency of lightning protection resistor (50hz) breakdown voltage value of 12kv-14kv, 10kv voltage the voltage and power cable. Increased high resistance lightning protection resistor, which guarantees the thunderstorm, under any weather conditions (including acid fog), power cable can be normal operation.

2) Under the adjustment of puncture ball head away from the high resistance of lightning protection resistor when the distance between the ball head, please

according to the local thunderstorm air resistance to breakdown voltage and cable voltage standard reasonably selected. Refer to use formula: mm clearance

number = (cable breakdown voltage resistance - arrester resistors)/ 0.2

Note: 0.2 number of mm resistance to breakdown voltage of air thunderstorm, unit (kV)/mm

Calculation example: mm gap== 90mm’

UCRH11

3) Air breakdown voltage resistance standard conditions recommended value for the 1kV/mm, when air humidity is big, air ionization in the rain, the influence of such factors as the air resistance to breakdown voltage is very low, even under low as a few hundred volts. We adopt is 0.2 kV/mm.

4) Resistance to breakdown voltage value of power cable, cable, please check your company shop instructions.

5) Due to the interference factors, accurately adjust air gap is more difficult recommended to choose 100 + 10 mm is more appropriate.

6) Conditions of use:

1# environment temperature for 40- +50C

2# is not more than 2000 m altitude

3# power frequency of 50- 60Hz

4# 35 m/s shall not exceed the maximum wind speed

5# The f0llowing region seismic intensity of 8 degrees.