用户定义故障由服务请求21(Service Request 21)来创建，这个服务请求在第九章描述。注意:户定义故障显示在PLC故障表中时，数值-32768(8000 16进制)会加到错误代码上去。例如，错误代码5将会显示为-32763上电时，PLC内的所有故障定位变量清0。有故障时，PLC将受影响的变量进行状态转换。在下列动作之一发生之前，故障变量保持故障状态:通过编程软件清除故障表或者清除整个存储器时，PLC故障表和I/O故障表清空。

() Annual Service Kit for MTV A1R for Serial Numbers

Westinghouse Electrical Frequency Meter – P/N KR – 241

Semiconductor Rectifier Device – P/N 11467821 80 Volt

NonMetallic Wire QQ-C-576B NSN 9525005424532 Cop tinned

Gear Box Assembly Honeywell 1282511-1 NSN 5845007907

Wiring Harness, Branched M-C365-20001 NSN 59950108309

Wiring Harness Copper Core Conductor 364052-1 Appear

STANDING WAVE RATIO INDICATOR CALIBRATOR, P/N 2562A

ROTARY MOTION SENSOR MODEL CI-6538

Retaining Arm B2988-1 54184 Appears Un!

Panasonic VHS Video Cassette Recorder – AG-DS850

MBA-2400 Lamp replacement for the Maxa Beam Searchlight

Bosch 1/3″ Monochrome Camera