代码 4503: [TO unit %1: ] H number %2 assigned more than once. H number linked again.
问题描述与安全警告
Siemens SINUMERIK 840D CNC 触发了严重的 [TO unit %1: ] H number %2 assigned more than once. H number linked again. 警报。需要由合格的操作员或维修技师立即处理，以防止在制造周期中对设备造成二次损坏或导致零件报废。在接触电气控制箱之前，请务必确保遵循标准安全和停机挂牌 (LOTO) 程序。
官方故障排除步骤
Parameters: %1 = TO unit %2 = H number Definitions: This error can only occur when MD10880 $MN_MM_EXTERN_CNC_SYSTEM= 1 or 2. The Power ON effective MD10890, $MN_EXTER N_TOOLPROG_MODE, bit 3 has been reset. On reconstructing data handling after Power ON, it has been found that different edges of the same TO unit have the same H number. They had been linked previ ously. They are linked again and MD10890 $MN_EXTERN_TOOLPROG_MODE, bit 3 is set again. Reaction: Alarm display. Remedy: H numbers must be assigned only onc e in a TO unit. Then, MD10890, $MN_EXTERN_TOOLPROG_MODE, bit 3 can be set = 0 and a restart can be performed. Program Continuation: Clear alarm with the Delete key or NC START.
Source: SINUMERIK 840D sl / 840Di sl / SINAMICS S120 Diagnostics Manual (DAsl, 03/2009)
Last reviewed: 2026-07-01 · Verified against the manufacturer’s official documentation.
关于 Siemens SINUMERIK 840D CNC 警报
由 Siemens 制造的工业控制器具有广泛的诊断系统，用于保护内部电路和机械连杆。当 SINUMERIK 840D CNC 出现类似 4503 的错误代码时，通常表示指令值与实际传感器反馈之间存在不匹配。
完整报警清单: 4014 Siemens SINUMERIK 840D CNC 代码s.
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