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IEC 61009-2-1:1991标准是针对剩余电流动作断路器（RCBO）的一般规则适用性进行规定的。这些RCBO独立于线路电压的功能，用于家庭和类似用途，并具有过电流保护功能。该标准主要包括以下内容：

1. 适用范围：该标准适用于额定电压不超过440V，额定电流不超过125A，频率不超过60Hz的剩余电流动作断路器（RCBO）。

2. 定义：该标准对RCBO的定义进行了详细说明，包括RCBO的构造、工作原理、额定参数等。

3. 一般规则适用性：该标准规定了一般规则适用于RCBO的要求，包括机械要求、电气要求、环境要求等。

4. 过电流保护：该标准对RCBO的过电流保护进行了规定，包括过载保护和短路保护。

5. 试验方法：该标准规定了RCBO的试验方法，包括机械试验、电气试验、环境试验等。

6. 标志和包装：该标准对RCBO的标志和包装进行了规定，包括产品标志、包装要求等。

IEC 61009-2-1:1991标准的制定，对于保障家庭和类似用途的电气安全具有重要意义。该标准规定了RCBO的一般规则适用性，确保了RCBO的安全可靠性和稳定性，为RCBO的生产和使用提供了技术支持和保障。

相关标准：
1. IEC 61009-1:1990 Residual current operated circuit-breakers without integral overcurrent protection for household and similar uses (RCCBs) - Part 1: General rules
2. IEC 61009-3:1996 Residual current operated circuit-breakers with integral overcurrent protection for household and similar uses (RCBO's) - Part 3: Applicability of the general rules to RCBO's functionally depent on line voltage
3. IEC 61008-1:1996 Residual current operated circuit-breakers without integral overcurrent protection for household and similar uses (RCCBs) - Part 1: General rules
4. IEC 61008-2-1:1996 Residual current operated circuit-breakers without integral overcurrent protection for household and similar uses (RCCBs) - Part 2-1: Applicability of the general rules to RCCBs functionally indepent of line voltage
5. IEC 61008-2-2:1996 Residual current operated circuit-breakers without integral overcurrent protection for household and similar uses (RCCBs) - Part 2-2: Applicability of the general rules to RCCBs functionally depent on line voltage