免责声明
Littelfuse产品并非为以下用途而设计，也不应被用于这些用途：包括但不限于汽车、航空航天、医疗、救生、维生、核设施、高可靠性应用、用于手术植入体内的装置，或者在产品故障或运行无法达到理想状态的情况下会造成人身伤害、死亡或财产损失的任何其他应用。除非在适用的Littelfuse产品文档中已有明确说明。 如果将产品用于相关Littelfuse文件中未明确说明的任何其他用途，则产品不享受Littelfuse质保。 如果将产品用于相关Littelfuse文件中未明确说明的其他用途，则Littelfuse不会为因此造成的任何索赔或损失承担责任。 除非经Littelfuse另行许可，否则Littelfuse产品的销售和使用应遵守Littelfuse销售条款与条件。 "Littelfuse"包括Littelfuse, Inc.及其所有附属实体。
The THD7 Series utilizes only two terminals connected in series with the load. Interval timing mode is achieved by using a small portion of the AC sine wave allowing sufficient voltage for circuit operation. The THD7 Series can be used for interval or delay-on break timing. It is designed to operate large loads directly, such as motors, heater elements, and motor starters.
Operation (Interval)
Upon application of input voltage, the output energizes and the time delay begins. The output remains energized throughout the time delay. At the end of the time delay the output de-energizes and remains de-energized until power is removed. 重置: Removing input voltage resets the time delay and
the output.
工作（断开延迟）
Upon closure of SW1, the load energizes and the timer is reset (zero voltage across its input terminals). Opening SW1 re-applies input voltage to the timer, the load remains energized and the time delay begins. At the end of the time delay the output de-energizes. If SW1 is open when power is applied, the load will energize for the time delay then de-energize. 重置: Re-closing SW1 resets the timer.