Control and Protective Switching Device

Application: KB0 is mainly used to make, carry and break current under normal condition including specified overload condition as well as current under specified abnormal condition like short circuit for AC 50(60)Hz power system with rated voltage up to 690V and rated current from 0.25A to 125A. Functions: KB0 adopts modularized single structure and integrates main function of traditional circuit breaker ,fuse, contactor, overload (or over current, open phase) relay, starter and isolator, it owns remote automatic control and local direct manual control function as well panel indication and electrical signal alarm function, it also has coordinated time-current protection characteristic (three sections protection characteristics of inverse time delay, definite time delay and instantaneous), shown as fig. 4. Functional module and accessory can be selected and used to realize control and protection for general (infrequent start) motor load, motor load of infrequent start and distribution circuit load according to requirement. Application of Module And Accessory 1.Main body: it owns short circuit protection (similar to the short circuit protection function of MCCB and fuse), automatic control, local operation and indication function. 2.Thermomagnetic release: it owns overload and over current protection function etc, the setting current value includes overload inverse time delay and over current definite time delay, all of the setting current values are available. It can be classified into kinds of forms, types and specifications according to principle and application. 3.Auxiliary contact (Mechanical passive type F and L): coupled with contact of main circuit, it owns electric control and indication function, it can be classified into kinds of specifications according to contact couples. It can provide 8 couples of auxiliary contact at the same time. 4.Shunt release: it realizes remote tripping and circuit breaking function. 5.Remote recloser: it realizes remote reclose (reset) function. 6.Signal alarm contact (mechanical passive): coupled with operation mechanism when equipped with F type auxiliary contact, it owns work state and fault reason indication function. It owns 3 couples of signal alarm contact and can provide 2 couples of signal alarm contact at the same time. 7.Isolating auxiliary contact (mechanical passive): coupled with isolating type operation mechanism, it realizes isolation indication function of control circuit or (and) auxiliary circuit. It can provide 2 couples of auxiliary contact at the same time. 8.Acousto-optic alarm module: it realizes acousto-optic alarm under fault and short circuit condition. 9.Panel operation mechanism: mounted on panel of complete unit, the KB0 can be operated on the spot without starting, including making, breaking and reclose (reset). It owns different types and specifications at different installation directions. 10.Control circuit transfer module: it realizes control circuit AC/DC switching and low voltage control (e.g., PLC direct control) function. Main technical data: 1) Two outline dimensions (C and D frame size): 3-pole and 4-pole 2) Current ratings: C Frame: 12A, 16A, 18A, 32A, 45A; D Frame: 45A,63 A,100A,125A 3) setting current: 0.16A 125A 4) Short-circuit break capacity:a) 35kA for type C (economic) b) 50kA for type Y (standard) c) 80kA for type H (high capacity) 5) Opening time under prospective short-circuit current is 2 3ms, at current limiting of 0.2 and below Advantage of Product 1.Compared to system composed of separate element a. control and protection characteristic KB0 composed the function of circuit breaker (fuse), contactor, overload relay, auxiliary apparatus. It can perfectly solve the matching problem of protection and control between elements, which is insoluble or difficult to solve by separate element, so as to make the matching of protection and control characteristic more perfect and more reasonable (three sections protection characteristic of inverse time delay, definite time delay and instantaneous), the right single-structure product can be selected instead of various traditional apparatuses, including the one from power supply inlet terminal to load without derating, only according to load power or current, which has greatly reduced designer’s work load. b. operation reliability and continuity performance KB0 can be put into running without maintenance after breaking short circuit current, that means it owns operation continuity performance after breaking short circuit fault: after KB0 is processed by short circuit current breaking test, it still owns AC-44 electrical life not less than 1500times, which is unreachable for system composed of separate element like circuit breaker, this characteristic has greatly improved the operation reliability and continuity performance of system, meanwhile, the Ics denotes 80kA, ranking highest in China and at the top in the world. c. Energy saving and material saving The KB0 owns small volume, small installation area, non-contact of separate element, small circuit heating, energy saving and material saving and other advantages. 2.Compared to moulded case circuit breaker a. high breaking capacity and short arcing distance characteristic The KB0 reaches a rated short circuit breaking capacity Ics (o-co-co) of 80kA for high breaking type, 50kA for standard type and 35kA for economic type under 380V, the breaking time is only 2 3ms under 50 prospective short circuit current, with current limiting factor of 0.2 and below, it has reached the leading level of moulded case circuit breaker and current limiting level of fuse, greatly restricting the moving and thermal impact to system due to short circuit current. The arcing distance of KB0 is 20 30mm only. b. protection setting current with adjustable characteristic Both thermal tripping (inverse time delay) current and magnetic tripping (definite time delay) current of KB0 are adjustable on panel, it means that besides the regular thermal current can be set according to load power, the over current protection setting current can be set on panel (setting range of power distribution load is 3 6Ie, setting range of motor load is 6 12Ie). It overcomes the shortcoming that short circuit protection setting current of moulded case circuit breaker can’t be set after leaving factory, which makes the KB0 product still own excellent short circuit protection function even if it is mounted at the end of circuit and the short circuit current is low. 3.long service life and simple operation characteristic compared to contactor The mechanical life of KB0 reaches 5×106 1×107 times, and the AC-43 electrical life of it reaches 1×106 1.2×106 times, it’s available either for local manual operation or for remote automatic control. With advanced contact and electromagnetic system separation design, it has effectively restrained secondary bounce of contact and greatly enhanced the electrical life of product, it’s especially suitable for severe place of heavy load start.