交流真空断路器ZN110/DZM-12kV
用途
ZN110/DZM-12kV户内高压交流真空断路器是三相交流50Hz额定电压12kV户内变配电装置，尤其适用于开断重要负载及频繁操作、免维护的场所。
结构及特点
该断路器采用新型双稳态磁力操动结构及电子控制系统，零部件数量少，操作更为简单、**、可靠。采用位置传感器作为切换开关，避免了机械式转换开关触点切换不可靠、使用寿命低的缺陷，无故障动作次数达10万次，实现免维护。完善的电子与机械防误操作联锁，避免故障的产生，并及时提供故障信号，可实现远程遥控操作。正常操作功耗仅为4W，对电源要求低，操作电源电压为AC/DC85-260v。
订货须知
订货时须注明产品型号、名称及订货数量；额定电压、额定电流及额定开断电流；额定操作电压；备品备件名称、数量；有无特殊要求。
OVP Overview
Requests for a compact, explosion-proof protection device led to the design of the Over Voltage Protector (OVP). With the input of potential users and Dairyland's existing base of clients, the OVP was designed and tested to meet the requirements for Class I, Division 1 & 2, Group B, C, D classified locations. Independent testing and product listing was performed by Underwriter’s Laboratories (UL), authorizing the use of the UL and C-UL (Canada) marks. The device has also been tested and approved by UL/Demko for compliance to the ATEX directive for Zone 2 applications, and carries the CE mark for Zone 2.
The OVP is unlike other "arrester" type products. Instead of a gapped design, the OVP uses solid-state switching components to conduct at very low voltages, providing the best over-voltage protection. Rated for AC fault current as well as high values of lightning surge current, the OVP can be applied to sites where a spark-gap arrester or metal oxide varistor would be inappropriate. The OVP is a totally unique product for the corrosion prevention industry.
Note: the OVP is not recommended where steady-state AC voltage exists between the connection points, typically induced AC voltage.
Features & Characteristics
The only fail-safe "arrester" on the market (i.e., fails shorted).
Solid-state design eliminates arcing.
Conduction at much lower voltages than gapped arresters.
Rated for AC fault current and lightning surge current.
Suitable for submersed or above-ground locations.
UL, C-UL listed explosion-proof design.
Corrosion resistant nickel finish.
Typical Applications
Insulated Joint Protection
Airport Fueling Systems Isolation / Bonding
Decoupling Equipment Grounds
OVP Overview
Requests for a compact, explosion-proof protection device led to the design of the Over Voltage Protector (OVP). With the input of potential users and Dairyland's existing base of clients, the OVP was designed and tested to meet the requirements for Class I, Division 1 & 2, Group B, C, D classified locations. Independent testing and product listing was performed by Underwriter’s Laboratories (UL), authorizing the use of the UL and C-UL (Canada) marks. The device has also been tested and approved by UL/Demko for compliance to the ATEX directive for Zone 2 applications, and carries the CE mark for Zone 2.
The OVP is unlike other "arrester" type products. Instead of a gapped design, the OVP uses solid-state switching components to conduct at very low voltages, providing the best over-voltage protection. Rated for AC fault current as well as high values of lightning surge current, the OVP can be applied to sites where a spark-gap arrester or metal oxide varistor would be inappropriate. The OVP is a totally unique product for the corrosion prevention industry.
Note: the OVP is not recommended where steady-state AC voltage exists between the connection points, typically induced AC voltage.
Features & Characteristics
The only fail-safe "arrester" on the market (i.e., fails shorted).
Solid-state design eliminates arcing.
Conduction at much lower voltages than gapped arresters.
Rated for AC fault current and lightning surge current.
Suitable for submersed or above-ground locations.
UL, C-UL listed explosion-proof design.
Corrosion resistant nickel finish.
Typical Applications
Insulated Joint Protection
Airport Fueling Systems Isolation / Bonding
Decoupling Equipment Grounds
Technical Comparisons
Comparison of Dairyland OVP to Gapped Arresters
Zinc grounding cells
These cells consist of two zinc rods, with insulation material to separate them, in a conductive backfill material, packaged in a bag. The insulation or separator leaves the zinc rods reasonably close together without touching. The backfill material, such as bentonite, promotes conduction and contact with the surrounding earth, as the package is buried near the points it is connected to. A wire lead attaches each rod to a point of interest, such as across an insulated flange, or between a pipeline and ground. The concept for protection is that the zinc rods will allow separation of the two structures, and minimize the DC cathodic protection current flow under normal conditions. Under over-voltage conditions, the small separation between the rods, and the conductive backfill will allow current to flow between them, draining the unwanted current.
There are several ways in which the zinc grounding cells will not perform very well for this application. First, the package must be buried. If the application is protection of insulated joints from over-voltage (lightning, for example), and the joint is above ground, the leads that connect to the joint will be at least several feet each. Under lightning surge conditions, this affords little or no over-voltage protection to the insulated joint, as leads have inductance, which lightning sees as a high impedance, and therefore creates a large voltage drop in the leads. Lightning protection for insulated joints is best done by locating a device directly across the joint, which cannot be done with zinc grounding cells, as compared to the Dairyland OVP.
Another electrical problem comes from AC power system fault current. Zinc grounding cells are generally not sized for handling any significant fault current.
