The Siemens S7-300 is a PLC for mid- to high-performance applications. It features a modular and fanless design, robustness, easy expansion and extensive communication capabilities, easy implementation of distributed architectures, and a user-friendly interface.
1. Install and assemble the guide rails
Prepare a 2-meter-long assembly rail for installation. The specific steps are as follows:
(1) Cut the 2-meter-long assembly guide rail to the required length.
(2) Mark the four holes for installing the fixing screws and the one hole for protecting the conductor bolt.
(3) If the guide rail is longer than 830mm, additional holes must be provided to secure it with more screws. Mark these holes along the groove in the middle of the guide rail (as shown in Figure 1), with a spacing of approximately 500mm.
① Holes for grounding wire bolts; ② Grooves for drilling additional holes for mounting screws; ③ Holes for mounting screws;
④ Additional holes for mounting screws; ⑤ Holes for mounting screws
Figure 1 Guide rail installation
(4) Drill these marked holes. The diameter of the M6 screw hole is 6.5 + 0.2 mm.
(5) Install an M6 bolt to secure the grounding wire.
(6) Confirm the PLC clearance after the guide rail is installed (as shown in Figure 2).
Figure 2. PLC gap after installation
2. Install the module on the assembly guide rail.
Starting from the left side of the rack, mount the modules onto the rails in the following order: power module first, then CPU, and finally SM/FM/CP/IM modules. The specific steps are as follows:
(1) As shown in Figure 3, insert the bus connectors into the CPU and SM/FM/CP/IM. Each module, except the CPU, has a bus connector. When inserting the bus connectors, you must start with the CPU. Disconnect the bus connector from the "last" module in the assembly, as the "last" module does not accept bus connectors.
Figure 3 Bus connector insertion method
(2) As shown in Figure 4, hang all the modules on the guide rail in the specified order ①, slide to the module closest to the left ②, and then rotate downwards ③.
Figure 4 Module Installation Method
(3) Tighten the module with screws, as shown in Figure 5.
3. Tagging Module
(1) Assign slot numbers. Each installed module should be assigned a slot number, which will make it easier to assign modules in the STEP7 configuration table.
(2) Attach the slot number to the module. First, take the corresponding slot number to the front of the relevant module, then place the latch into the opening of module ①, and finally press the slot number into module ②. The slot number will then disconnect from the wheel. Figure 6 illustrates this process.
