描述
根据统计资料表明：在PLC控制系统的故障中，CPU占5%，I/O接口占15%，输入设备占45%，输出设备占30%，线路占5%。前二项共20%故障属于PLC的内部故障，它可通过PLC本身的软、硬件实现检测、处理；而其余80%的故障属于PLC的外部故障。因此，PLC生产厂家都致力于研制、发展用于检测外部故障的专用智能模块，进一步提高系统的可靠性。
UFM GDN-1-5-G-S-O UNIVERSAL FLOW MONITOR B-H NO 1
Asco TriPoint SC11D Pressure and Temperature control
HONEYWELL BURNER CONTROL RM7896 D 1027 RM7896D1027
MITSUBISHI MELSEC A J65FBTA2-16T-S1 AJ65FBTA2-16T-S1 CC
Fairchild 24XFS-10840002 M/P Converter EB-1828
MAHR ZENTIMESS 0-1″ MARAMETER GAGE 0-25 .0005″ D.B.P
FLEX-KLEEN T16063 SMART TIMER MODULE
1 1/4″ CASH VALVE UNITED BRASS WORK PRESSURE REGULATOR
2″ BURLING BD2.0-4BB6130 pressure reducing Valve 700wog
Parker Schrader BELLOWS Pneumatic M05825245 MAN VALVE
