西门子单相电源模块6EP1331-2BA00

有源现场分配器 AFD8

有源现场分配器 (AFD) 可以在 Division 2, Zone 2 或 Zone 22 环境中运行。它具有以下型号：

因此，一个 AFD4、AFD4 RAILMOUNT 和 AFD4 FM 可以连接Zui多 4 个现场设备，一个 AFD8 可以连接Zui多 8 个符合标准的 PROFIBUS PA 现场设备，它们通过防短路分支总线接口连接到具有自动总线端接功能的 PA 现场总线网段（总线型/环型）。

可通过 PA 路由器将此现场总线网段连接到一个单一或冗余 PROFIBUS DP，因此，可将其无缝集成到 SIMATIC PCS 7 过程控制系统中。

每个现场总线网段可运行Zui多 8 个有源现场分配器 AFD，总共可连接 31 个现场设备。现场设备的数量受到现场设备电流消耗的限制。对于现场设备，每条分支总线的Zui大电流为 60 mA，每个总线段的Zui大电流为 1 A。

可在运行期间更换环网网段中的 AFD 而不会使该网段出现故障。

为了达到 IP66 防护等级的要求，必须使用接头对未使用分支线路接口进行保护。

Machine manufacturers and manufacturing plants must ensure that their machines or plants cannot cause danger due to malfunctions in addition to the general risks of electric shock, heat or radiation.

In Europe, for example, compliance with the Machinery Directive 2006/42/EC is legally stipulated by the EU work safety directive. In order to ensure compliance with this directive, it is recommended that the corresponding harmonized European standards are applied. This triggers the "assumption of conformity" and gives manufacturers and operators the legal security in terms of compliance with both national regulations and EU directives. The machine manufacturer uses the CE marking to document the compliance with all relevant directives and regulations in the free movement of goods.

Functional safety is specified in various standards. For example, EN ISO 12100 specifies standards pertaining to machine safety (risk assessment and risk reduction). IEC 61508 specifies basic requirements for electronic and programmable safety-related systems. EN 62061 (only applicable for electrical and electronic control systems) and EN ISO 13849‑1, which has replaced EN 954‑1, define the functional and safety-related requirements of safety-oriented control systems.

The above-mentioned standards define different safety requirements that the machine has to satisfy in accordance with the risk, frequency of a dangerous situation, probability of occurrence and the opportunities for recognizing impending danger.