描述
至于程序互换的问题，至少到目前为止尚是一个努力的方向。只有在每个PLC的供应厂商所提供的PLC产品都真正遵循IEC61131-3的标准，而且其编程系统的具体实现又切实符合IEC61131-8《编程语言的应用和实现导则》，并通过PLCopen这个国际组织对各种编程语言（LD、SFC、FBD、ST和IL）的一致性测试，还要解决不同PLC的存储地址资源的对应互换，才有可能实现名副其实的程序互换。
ELETTROMECCANICA 4219U2160 MARINE ELECTRIC PUMP
STI MINISAFE-B MS4312BX SAFETY CURTAIN 4268-70120 9708
1SET STI MINISAFE-B MS4316B SAFETY CURTAIN TRANSMITTER
OMEGA FMA-5606 GAS FLOW METER RANGE 0-500
OMEGA FMA-5603 GAS FLOW METER RANGE 0-50 FMA5603
OMEGA FMA-5605 GAS FLOW METER RANGE 0-200 FMA5605
2 1/2″ Hy-Grade Check Valve 101-2.5G-1AFI IT6660 150RF
2″ Powers Flowrite REGULATING ACTUATED Valve VEE 1E4 RA
1/2″ Burkert Air Actuated angle piston valve 49Z8 2509
Varian Electrical Raceway for Cable Tester
Foxboro E94-QXXL stcTemperature Transmitter PR-239
FLOTECT Flow Switch for Hazardous Locations MODEL V42U
POWERMAX II 1.8 STEP MOTOR P22NRXB-LNN-NS-00 PACIFIC SC
