| Q-1: According to the chart above, Bestact has a large switching capacity, doesn't it? A : That's right. As compared with conventional reed switches, Bestact has approximately hundred times larger switching capacity. But this is not all. Bestact also has the following advantageous features; * Low contact resistance and high stability * Little or no switching surge * Free from sticking even without contact protection circuits * Large DC breaking capacity available * Excellent resistance to vibration and shock Q-2: Why does the dual contact construction provide Bestact with such large capacity? A : Because the optimum materials and mechanism are used in both electrical circuit section and magnetic circuit section. And in design, we gave consideration to contact shape, contact pressure, breaking speed and over current capacity. Q-3: Why is the Bestact free from contact welding and sticking? A : In a word, it is because Bestact has a very large switching capacity. Conventional reed switches have a switching capacity of only around 50VA (resistive) at the most. Consequently they frequently suffer from contact welding - due to the electrostatic storage (capacitive) capacity of long cable runs or contact sticking the inrush current of inductive loads, which is due to insufficient repulsive force when the circuit is closed. That's why conventional reed switches normally need contact protection circuits to prevent these faults. In addition to the switching capacity of 240VAC 30A (7kVA), Bestact mechanically charges the return spring and imparts a hammering effect to open the contacts with a large separating force and at high speeds. Made of newly developed heat-resistant material, Bestact will not contact weld or stick, even without contact protection circuitry such as R/C snubbers and diodes, making it possible to use it like a normal contact. Q-4: What is hammering effect? A : It exhibits the function of a bow and arrow. When the armature loses pull force, the movable contact is instantaneously snapped away by the repulsive energy of the armature return spring and stationary contact (contact spring). This helps in breaking small molten contact bridges that often happen in DC circuits. |