1756-OV16E/AB智能制造
过程映像输入/输出（I/Q）、变量存储器V、内部存储器位M、定时器T、计数器C等属于全局变量。S7-200的程序组织单元(ProgramOrganizationalUnit，简称为POU)包括主程序、子程序和中断程序。每个POU均有
自己的64字节局部变量，局部变量只能在它所在的POU中使用。与此相反，全局变量可以在各POU中使用。
下面是子程序可以使用的局部变量：
1)TEMP(临时变量)是暂时保存在局部数据区中的变量。只有在执行该POU时，定义的临时变量才被使用，POU执行完后，不再保存临时变量的数值。
2)IN是由调用它的POU提供的输入参数。
3)OUT是返回给调用它的POU的输出参数(子程序的执行结果)。
4)IN_OUT是输入_输出参数，其初始值由调用它的POU传送给子程序，并用同一变量将子程序的执行结果返回给调用它的POU。
1756-OV16E/AB智能制造
1756-OA16 74-265 VAC OUTPUT 16PTS
1756-OA16I 74-265 VAC ISOLATED OUTPUT 16PTS
1756-OA8 74-265 VAC 2 AMP OUTPUT 8PTS
1756-OA8D 74-132 VAC DIAGNOSTIC OUTPUT 8PTS
1756-OA8E 74-132 VAC ELEC FUSED 2A OUTPUT 8PTS
1756-OB16D 19-30 VDC DIAGNOSTIC OUTPUT 16PTS
1756-OB16E VDC ELEC FUSED OUTPUT 16PTS
1756-OB16I VDC ISOLATED OUTPUT 16PTS
1756-OB32 VDC OUTPUT 32PTS
1756-OB8 VDC 2 AMP OUTPUT 8PTS
1756-OB8EI VDC ISOLATED ELEC FUSED OUTPUT 8PTS
1756-OC8 VDC 2 AMP OUTPUT 8PTS
1756-OF4 ANALOG OUTPUT
1756-OF6CI ISOLATED ANALOG INPUT-CURRENT/VOLTAGE 6PTS
1756-OF6VI ISOLATED ANALOG INPUT-CURRENT/VOLTAGE 6PTS
1756-OF8 ISOLATED ANALOG INPUT-CURRENT/VOLTAGE 8PTS
1756-OH8I VDC ISOLATED 2 AMP OUTPUT 8PTS
1756-ON8 VAC 2 AMP OUTPUT 8 PTS
1756-OV16E VDC ELEC FUSED SINKING OUTPUT 16PT
1756-OW16I N.O. ISOLATED RELAY OUTPUT 16PTS
1756-OX8I N.O./N.C. ISOLATED RELAY OUTPUT 6PTS
1756-PA72 VAC POWER SUPPLY
1756-PA75 VAC POWER SUPPLY
1756-PB72 VDC POWER SUPPLY
1756-PB75 VDC POWER SUPPLY
1756-PLS PROGRAMMABLE LIMIT SWITCH MODULE
1756-TBCH 36 PIN SCREW CLAMP BLOCK W/STANDING HOUSING
1756-TBE EXTENDED DEPTH TERMINAL BLOCK HOUSING
1756-TBNH 20 POSITION NEMA SCREW CLAMP BLOCK
1756-TBS6H SPRING CLAMP BLOCK
1756-TBSH SPRING CLAMP BLOCK
1756-TCO2 INTERFACE TRANSCEIVER CABLE
1756-TC15 INTERFACE TRANSCEIVER CABLE
