S7-300的模块机架（起物理支撑作用，无背板总线），西门子提供五种规格的导轨。
电源模块（PS）
将市电电压（AC120/230V）转换为DC24V，为CPU和24V直流负载电路（信号模块、传感器、执行器等）提供直流电源。输出电流有2A、5A、10A三种
正常：绿色LED灯亮
过载：绿色LED灯闪
短路：绿色LED灯暗（电压跌落，短路消失后自动恢复）

3SB39021AA
3SB39031AA
3SB39051AA
3SB39061AA
3SB39210AA
3SB39210AB
3SB39210AC
3SB39210AD
3SB39210AH
3SB39210AJ
3SB39210AK
3SB39210AX
3SB39220AV
3SB39230AV
3SB39250AV
3SB39300CA2
3SB39300CA3
3SB39300CA4
3SB39300CA5
3SB39300CA6
3SB39300CA7
3SB39300EA1
3SB39300EA2
3SB39300EA5
3SB39300EA6
3SB39300EA7
3SB39300GA2
3SB39300GA3
3SB39300GA4
3SB39300GA6
3SB39300GA7
3SB39306CA7
3SB39310AA
3SB39310AC
3SB39420AX
3SE21000E
3SE21001B
3SE21001C
3SE21001D
3SE21001DV000AH3

6ES71532BA020XB4
6ES71532BA020XB5
6ES71532BA810XB0
6ES71532BA820XB0
6ES71532BB000XB0
6ES71533AA000XB0
6ES71533AA010XB0
6ES71534AA000XB0
6ES71534AA010XB0
6ES71541AA000AB0
6ES71541AA010AB0
6ES71542AA000AB0
6ES71542AA010AB0
6ES71544AB000AB0
6ES71544AB100AB0
6ES71546AB000AB0
6ES71548AB000AB0
6ES71560AA010XA0
6ES71570AA810XA0
6ES71570AA820XA0
6ES71570AC000XA0
6ES71570AC800XA0
6ES71570AC810XA0
6ES71570AC820XA0
6ES71570AC830XA0
6ES71570AD800XA0
6ES71570AD810XA0
6ES71570AD820XA0
6ES71570AF810XA0
6ES71570AF820XA0
6ES71570AF830XA0
6ES71580AA010XA0
6ES71580AD000XA0
6ES71580AD010XA0
6ES71583AD000XA0
6ES71583AD010XA0
6ES71740AA100AA0
6ES71784BH000AE0

3RV10111GA20
3RV10111HA10
3RV10111HA15
3RV10111HA20
3RV10111JA10
3RV10111JA15
3RV10111JA20
3RV10111KA10
3RV10111KA15
3RV10111KA20
3RV10210AA10
3RV10210AA15
3RV10210BA10
3RV10210CA10
3RV10210CA15
3RV10210DA10
3RV10210DA15
3RV10210EA10
3RV10210EA15
3RV10210FA10
3RV10210FA15
3RV10210GA10
3RV10210GA15
3RV10210HA10
3RV10210HA15
3RV10210JA10
3RV10210JA15
3RV10210KA10
3RV10210KA15
3RV10211AA10
3RV10211AA15
3RV10211BA10
3RV10211BA15
3RV10211CA10