PLC drawings in DesignSpark Electrical
When you have PLCs, Digital controls circuits, Safety controllers, Drives, Inputs and Outputs, you may need special symbols to represent your design. First for the topology you can use the different front views to illustrate the configuration of the PLC modules. This will show how they are to be laid out and where in the cabinet.
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For detailed schematic design of these devices within DesignSpark Electrical you have many possibilities. You could either insert a dynamically sized black box symbol, a fixed length complete PLC card symbol or a specific I/O symbol for each channel of the PLC, to illustrate the different functions served by the control device.
Here is how:
- Black-box symbols: From the schematics ribbon, use the Insert Black box symbol and assign a part to it. The size of this black-box can be increased or reduced. As you draw wires from that black box symbol, to show the connections to that device, you can update connections to that black box symbol. In the circuit types, if you see a black box circuit type in red, then you can grab it and then drag and drop it on the corresponding circuit where it has only one terminal. TIP: if it is a single circuit, which has two terminals, for example, those of an NO contact, then draw the wire, let us say, as going up into the black box symbol and then bend right and then another right to come down and out of that black box symbol, showing a circuit so that the entry and exit points become the terminals, of that NO contact circuit.
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- Complete PLC card symbols: From the symbols Library menu in the Library Ribbon, you can add a new symbol, and draw the shape of the card, keeping in mind the different spacing between the inputs/outputs, the Power and COM terminals. There are several ready-made symbols that are available which can be copied and pasted as new symbols to speed up the process of drawing these new symbols. The details like terminal numbers, mnemonics or channel addresses of the PLC, can be inserted onto this card symbol as text using multilingual text in the Draw ribbon.
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- Individual I/O symbols: From the insert symbol menu, you can use the individual I/O symbols and add any description to that I/O so that it will be clearly seen on the drawing.
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You can complete these control designs quickly by having frequently used modules and sub-systems saved in the macros library.
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For example, a sensor output can already have all the circuitry drawn, some cables assigned and all the BoM parts for terminals and the sensor already assigned. Once this is prepared, all you need to do is to drag and drop that macro circuit on to the drawing, to go with the PLC symbol, in one of the forms, as discussed above.
Comments
2 comments
Please can you post a "Howto"? The management of PLCs and their i/o connections is causing difficulty and a more detailed explanation would be useful. It's difficult to see the details in the pictures above.
The problem is tha PLCs often need to interact with elements on other sheets in the drawing. I.E. a voltage input may come from the output of a VSD where the voltage represents the current flow in the load...another example is where a volt free relay contact is switching a contactor coil.
I notice that several features related to PLC's give either error messages or the command appears to have no effect.
Thanks for any assistance.
Agreed with previous comment, there is much need for an illustrated How-to write-up or video. PLC's need specific info such as a slot, channel address, + or COM, etc. Also, wire numbering should have the option to match the slot/channel number. Not evident..
Personally I am confused as to how you create a new PLC symbol from "insert symbol" menu, that matches up with specific PLC manufacturer layouts. Does this have to be a two step process or can a specific manufacturer PLC card directly be inserted and show all it's terminals?
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