ZX18V derived series is applicable to the circuit with AC50HZ 1140 voltage and DC voltage 1000, mainly used as the resistor for the starting and braking of the variable frequency with high power and high current as well as the high voltage transformer neutral earth resistor. The resistor is shaped in bars from raw materials, with holes at both ends for assembly, and the insulation porcelain parts between the sheets within which the insulation sleeves are put for second time insulation, to reach the good insulation and avoid short circuit. The resistor component is connected by argon-arc weld. The electric contact is reliable and fine. The visual structure of products includes the open type, the indoor protection and the outdoor protection.