LHQ 35kV Large Cross-Section Power Lightning Arrester

Overview

35kV large cross-section power cables, as well as power cables with voltage grades of 66kV, 110kV, and above, are typically single-core cables. One end of the cable's metal sheath is interconnected and grounded, while the other end remains ungrounded. When lightning or internal overvoltage waves travel along the cable core, a high impulse overvoltage may occur at the ungrounded end of the cable's metal sheath. Alternatively, when a system short-circuit current passes through the cable core, a high power frequency induced overvoltage can also occur at the ungrounded end of the sheath. Such overvoltages can damage the insulation of the cable's outer protective layer, leading to multiple grounding faults in the metal protective layer. This can severely affect the normal operation of the power cable and potentially reduce its service life. As a result, the power industry standard DL/T401-1991 "Guidelines for the Selection of High-Voltage Power Cables" mandates the use of a cable sheath protector to limit the induced voltage and fault overvoltage on the metal shielding layer (or metal sheath) of the power cable.

Product Features

The silicone rubber cable sheath protector designed by our company for cable lines with one end grounded and cross-connected offers the following advantages:

• Utilizes high-quality ZnO chips with large capacity and low residual voltage, ensuring a high current capacity and superior protection ratio.

• Effectively limits and reduces power frequency induced overvoltage and impulse overvoltage in the metal sheath of the cable.

• The silicone rubber jacket is integrally molded, providing excellent sealing, strong anti-fouling capabilities, lightweight, compact size, anti-collision properties, and resistance to heat, cold, aging, and maintenance-free operation.

• When a discharge counter or monitor is installed, it can automatically and accurately record the number of operations and the operating quality of the protector under various overvoltages.

LHQ 35kV Large Cross-Section Power Lightning Arrester

Electrical parameters of cable sheath protector

model	Rated voltage of the system (kV)	Power frequency withstand voltage/time kV/s	Residual voltage ≤ kVp under 10kA lightning impulse current	DC U1mA reference voltage ≥ kV	2ms square wave current capacity A	Leakage current at 0.75UimA ≤ μ A	Models of similar products currently circulating in the market that have not been labeled according to national standards
LHQ-6	10	1.9/4	4.6	2.1	400	50	BHO、BYL、 FBY、SHO、 BYLS、TBP-D
LHQ-10	35	3.6/4	8.7	4.0	400	50
LHQ-35	110	5/4	12	5.5	400	50
LHQ-110(1)	110	6/4	15	6.5	400	50
LHQ-110(II)	220	10/4	25	11.0	400	50
LHQ-220(1)	220	6/4	12	5.8	400	50
LHQ-220(II)	500	13.6/4	31	15.0	400	50
LHQ-500	10	7.5/4	8*	8.3	400	50

*Note: Residual voltage under lightning impulse current of 16k

Cable sheath insulation withstand voltage value (DL/T401-1991) "Guidelines for the selection of high-voltage power cables"

Cable rated voltage/system rated voltage Ue/U	1-minute power frequency withstand voltage kV	Lightning impulse withstand voltage kVp
37/63、48/63、64/100	24	37.5
127/220	24	47.5
190/330	24	62.5
290/500	24	72.5