| 摘要 |
PURPOSE:To reduce the power loss and to increase the reliability, by taking the contact switching time until the common contact opens from a normally closed contact and contacts a normally open contact, a half cycle or more of AC power input applied to the control terminal of a switching circuit. CONSTITUTION:When a control signal Ec is applied to a relay RL, the common contact (c) is driven and it opens from a normally closed contact (a), and AC power input AC is applied to control terminals 1, 2 of a switching circuit ZS via a load L and a resistance R1, tri-terminal thyristor T is conductive near the zero cross point of the power input AC, and the load current flows through the thyristor T. When the contact (c) is in contact with the normally open contact (b) to short- circuit the both ends of the thyristor T, the load current flowing to the thyristor T flows through the contacts (c) and (b). In this case, the contact switching time until the contact (c) is disconnected from the contact (a) and is brought into contact with the contact (b), is taken as a half cycle or more of the power input AC applied to the control terminal of the switching circuit, allowing to reduce the power loss and to increase the reliability. |
