ResourcesElectrical schematic symbols
Logic and PLC diagrams: sample DWG files and electrical template
Two complete control drawings of the same pump station on ISO A3 sheets. The logic diagram shows the control function with gates, bistables, a monostable and a counter; the PLC wiring diagram shows how the field devices connect to the input, output and analogue modules and to the 24 V DC supply. Each drawing has a signal or I/O list, notes and a filled-in title block, and every symbol is a block with its attributes filled in.
Free to use and modify in your own projects, including commercial ones. The ZIP holds the sample drawing, a template, a plot style table and a README; no add-in needed. The data in the drawing is made up, so it is not for design or construction. Provided as is, without warranty.
Level control logic
Pump station level control: level latch, auto and manual start, overload inversion, run command, run feedback supervision with a 10 s delay, a latched alarm and a daily start counter.
PLC I/O wiring
Pump station PLC wiring: power supply and CPU, a digital input module with four field devices, a relay output module with four loads, an analogue input module with two transmitters, and the 24 V DC and 0 V rails.
This sample uses these resources
The symbols are blocks from our own libraries, with their attributes filled in. The sheet and its title block come from our ISO A3 title block template. Download them to draw your own diagrams.
Title block templates (ISO A3 and more)Sheet frame and title block of this sample
PLC ladder logic and I/O symbols12 of its symbols are used here
Logic gate symbols (IEC 60617)4 of its symbols are used here
Flip-flops, multiplexers, op amps (IEC 60617)2 of its symbols are used here
Multiplexers, adders, decoders, counters (IEC 60617)1 of its symbols are used here
What is in the ZIP
- Level-Control-Logic-Sample.dwg
Sample drawing (DWG, AutoCAD 2018 format) - PLC-IO-Wiring-Sample.dwg
Sample drawing (DWG, AutoCAD 2018 format) - Electrical-Template-ISO-A3.dwt
Template (DWT) that the drawing was made on - CADXChange-Monochrome.ctb
Plot style table (CTB) that prints every colour black - README.txt
README with the layer list and how to use the files
Every ZIP holds its own drawing together with the template, the plot style table and the README.
The template
The electrical template has 16 layers with colours, line weights and linetypes (power circuits, busbars, control, signal, protective earth, enclosure boundaries, text and more), the text styles ISO-2.5 to ISO-5, the dimension style ISO-25 and an ISO A3 layout with a title block and revision table. The layer names are a common convention, not a standard; rename them to match your company's rules.
Layers defined
Every layer in the template with its colour, line weight and linetype, and how many objects of this sample are on it. Layers the sample does not use are still defined, ready for your own drawing.
| Layer | Colour | Line weight | Linetype | Used for | Level control logic | PLC I/O wiring |
|---|---|---|---|---|---|---|
| Electrical layers | ||||||
| ELEC-POWER | 1 | 0.50 mm | Continuous | Main power circuits | not used here | 5 |
| ELEC-BUS | 1 | 0.70 mm | Continuous | Busbars and heavy lines | not used here | not used here |
| ELEC-CONTROL | 4 | 0.25 mm | Continuous | Control circuits | not used here | 9 |
| ELEC-SIGNAL | 3 | 0.18 mm | Continuous | Signal, instrumentation and communication circuits | 34 | 47 |
| ELEC-PE | 2 | 0.35 mm | Continuous | Protective earth and bonding | not used here | not used here |
| ELEC-CABLE | 30 | 0.25 mm | DASHED | Cable, conduit and tray routes | not used here | not used here |
| SYMBOL | 7 | 0.25 mm | Continuous | Symbols (the layer the symbol libraries use) | 9 | 15 |
| ELEC-TERMINAL | 7 | 0.25 mm | Continuous | Terminals and connection points | not used here | not used here |
| ELEC-BOUNDARY | 5 | 0.18 mm | DASHDOT | Enclosure, panel and device boundaries | not used here | not used here |
| ELEC-MECH-LINK | 8 | 0.18 mm | DASHED | Mechanical links, interlocks and measuring links | not used here | not used here |
| ELEC-REF | 7 | 0.18 mm | Continuous | Reference designations (-QF1, -K2) | not used here | not used here |
| ELEC-WIRE-NO | 7 | 0.18 mm | Continuous | Wire numbers and cable labels | not used here | not used here |
| ELEC-XREF | 9 | 0.13 mm | Continuous | Contact and cross reference texts | not used here | not used here |
| ELEC-TEXT | 7 | 0.18 mm | Continuous | General text | 56 | 69 |
| ELEC-NOTES | 7 | 0.18 mm | Continuous | Notes and legends | 5 | 4 |
| ELEC-DIM | 3 | 0.18 mm | Continuous | Dimensions | not used here | not used here |
| Sheet and symbol layers | ||||||
| 0 | 7 | default | Continuous | Default layer, keep it empty | not used here | not used here |
| FRAME | 7 | default | Continuous | Sheet border | 5 | 5 |
| TITLEBLOCK | 7 | default | Continuous | Title block and revision table | 1 | 1 |
| VIEWPORT | 8 | default | Continuous | Layout viewport frame (does not plot) | 2 | 2 |
| DRAWING-AREA | 8 | default | Continuous | Boundary of the model drawing area (does not plot) | 2 | 2 |
Styles defined
The text styles, the dimension style and the linetypes that the template defines, so you do not have to set them up in each new drawing.
| Kind | Name | Settings |
|---|---|---|
| Text style | ISO | isocp.shx, 15°, variable height |
| Text style | ISO-2.5 | isocp.shx, 15°, 2.5 mm high |
| Text style | ISO-3.5 | isocp.shx, 15°, 3.5 mm high |
| Text style | ISO-5 | isocp.shx, 15°, 5 mm high |
| Text style | TB-en | Arial, used by the title block |
| Dimension style | ISO-25 | Text 2.5 mm, arrows 2.5 mm, extension lines 1.25 mm beyond the dimension line and 0.625 mm from the object, dimension lines 3.75 mm apart, 0 decimals |
| Linetype | Continuous | Solid line |
| Linetype | DASHED | Dashed |
| Linetype | DASHDOT | Dash-dot |
| Linetype | CENTER | Centre line |
| Linetype | PHANTOM | Phantom line |
| Linetype | HIDDEN | Hidden line |
Sheet and drawing setup
How the sheet is set up, so your own drawings print the same way.
- Sheet
- ISO A3 landscape, 420 × 297 mm.
- Layout
- One layout named ISO-A3, plotted at 1:1 on full-bleed A3 media, so the sheet has no printer margin.
- Border
- 20 mm from the left edge (binding side) and 10 mm from the other edges; the drawing area inside is 390 × 277 mm.
- Model space
- Units are millimetres. The drawing area is shown at 1:1, so 1 mm in the drawing is 1 mm on paper.
- Title block
- 160 × 79 mm at the lower right, with a four-line revision table above the company, project, title and approval fields.
- Text size
- 2.5 mm for labels and notes, 3.5 mm and 5 mm for headings.
- Linetype scale
- 1, so dashes are sized for plotting at 1:1.
- Plot style
- None set. Pick the CTB from the ZIP in the page setup for black-and-white plots.
Level control logic
Title block fields
The attributes of the title block. Double-click it to fill them in, or write them for a whole set of drawings with BlockSync.
| Attribute | Field on the sheet | Value in this sample |
|---|---|---|
| COMPANY | COMPANY | CADXChange |
| PROJECT | PROJECT | Pump Station Control |
| AREA | AREA | Pump station |
| SYSTEM | SYSTEM | 24 V DC |
| CLIENT | CLIENT | Sample |
| TITLE | DRAWING TITLE | Level control logic diagram |
| DRAWING_NO | DRAWING NO. | E-401 |
| CONTRACT_NO | CONTRACT NO. | — |
| REV | REV | A |
| DRAWN | DRAWN | — |
| CHECKED | CHECKED | — |
| APPROVED | APPROVED | — |
| DATE | DATE | 2026-10-21 |
| SCALE | SCALE | NTS |
| SHEET | SHEET | 1 |
| SHEET_OF | OF | 1 |
Revision table: R1 to R4, each with REV, DATE, DESCRIPTION and BY (16 attributes, empty in this sample).
Blocks in the drawing
The equipment list of the drawing: block name, symbol and how many times it is placed. BlockSync exports the same list from your own drawings.
| Symbol | Block | Placed |
|---|---|---|
 RS bistable | LGC_S01659_RS_BISTABLE | 2 |
 AND element | LGB_S01567_AND_ELEMENT | 2 |
 OR element | LGB_S01566_OR_ELEMENT | 1 |
 Negator | LGB_S01576_NEGATOR | 1 |
 Exclusive-OR element | LGB_S01574_EXCLUSIVE_OR_ELEMENT | 1 |
 Monostable, non-retrigger | LGC_S01675_MONOSTABLE_NON_RETRIGGER | 1 |
 Counter, decade | LGD_S01703_COUNTER_DECADE | 1 |
Equipment schedule
One row per placed symbol, read from the attributes of the blocks in the drawing: what is shown on the sheet, and the schedule attributes that were filled in but are not shown. BlockSync exports these same attributes from your own drawings.
| Tag | Description | Shown on the sheet | Filled in, not shown |
|---|---|---|---|
| RS1 | RS bistableLGC_S01659_RS_BISTABLE | FUNCTION = Level latch: set at high level, reset at low levelSTD_CLAUSE = IEC 60617-12 12-42-01STD_REF = S01659 | |
| A1 | AND elementLGB_S01567_AND_ELEMENT | FUNCTION = Auto start requestSTD_CLAUSE = IEC 60617-12 12-27-02STD_REF = S01567 | |
| O1 | OR elementLGB_S01566_OR_ELEMENT | FUNCTION = Start request, auto or manualSTD_CLAUSE = IEC 60617-12 12-27-01STD_REF = S01566 | |
| N1 | NegatorLGB_S01576_NEGATOR | FUNCTION = Overload inverted, healthySTD_CLAUSE = IEC 60617-12 12-27-11STD_REF = S01576 | |
| A2 | AND elementLGB_S01567_AND_ELEMENT | FUNCTION = Run commandSTD_CLAUSE = IEC 60617-12 12-27-02STD_REF = S01567 | |
| X1 | Exclusive-OR elementLGB_S01574_EXCLUSIVE_OR_ELEMENT | FUNCTION = Command and feedback differSTD_CLAUSE = IEC 60617-12 12-27-09STD_REF = S01574 | |
| T1 | Monostable, non-retriggerLGC_S01675_MONOSTABLE_NON_RETRIGGER | FUNCTION = Mismatch longer than 10 sSTD_CLAUSE = IEC 60617-12 12-44-02STD_REF = S01675 | |
| RS2 | RS bistableLGC_S01659_RS_BISTABLE | FUNCTION = Alarm latch, reset by acknowledgeSTD_CLAUSE = IEC 60617-12 12-42-01STD_REF = S01659 | |
| C1 | Counter, decadeLGD_S01703_COUNTER_DECADE | FUNCTION = Pump starts per daySTD_CLAUSE = IEC 60617-12 12-49-16STD_REF = S01703 |
Manufacturer, model and remarks are left empty on every block, ready for your data. The values are examples.
PLC I/O wiring
Title block fields
The attributes of the title block. Double-click it to fill them in, or write them for a whole set of drawings with BlockSync.
| Attribute | Field on the sheet | Value in this sample |
|---|---|---|
| COMPANY | COMPANY | CADXChange |
| PROJECT | PROJECT | Pump Station Control |
| AREA | AREA | Pump station |
| SYSTEM | SYSTEM | 24 V DC |
| CLIENT | CLIENT | Sample |
| TITLE | DRAWING TITLE | PLC input and output wiring |
| DRAWING_NO | DRAWING NO. | E-402 |
| CONTRACT_NO | CONTRACT NO. | — |
| REV | REV | A |
| DRAWN | DRAWN | — |
| CHECKED | CHECKED | — |
| APPROVED | APPROVED | — |
| DATE | DATE | 2026-10-21 |
| SCALE | SCALE | NTS |
| SHEET | SHEET | 1 |
| SHEET_OF | OF | 1 |
Revision table: R1 to R4, each with REV, DATE, DESCRIPTION and BY (16 attributes, empty in this sample).
Blocks in the drawing
The equipment list of the drawing: block name, symbol and how many times it is placed. BlockSync exports the same list from your own drawings.
| Symbol | Block | Placed |
|---|---|---|
 Normally closed contact to input | PLC_FIELD_CONTACT_NC | 2 |
 Pilot lamp from output | PLC_FIELD_LAMP | 2 |
 Transmitter, 2-wire 4-20 mA loop to analog input | PLC_FIELD_4_20MA_2WIRE | 2 |
 Digital input module, 8 channels | PLC_MOD_DI8 | 1 |
 Emergency stop (normally closed) to input | PLC_FIELD_ESTOP | 1 |
 Pushbutton (normally open) to input | PLC_FIELD_PUSHBUTTON | 1 |
 Digital output module, 8 relay outputs | PLC_MOD_DO8_RELAY | 1 |
 Relay or contactor coil from output | PLC_FIELD_COIL | 1 |
 Solenoid valve from output | PLC_FIELD_SOLENOID | 1 |
 Analog input module, 4 channels (4-20 mA / 0-10 V) | PLC_MOD_AI4 | 1 |
 Power supply module, 24 VDC | PLC_MOD_PSU | 1 |
 CPU module | PLC_MOD_CPU | 1 |
Equipment schedule
One row per placed symbol, read from the attributes of the blocks in the drawing: what is shown on the sheet, and the schedule attributes that were filled in but are not shown. BlockSync exports these same attributes from your own drawings.
| Tag | Description | Shown on the sheet | Filled in, not shown |
|---|---|---|---|
| 1 | Digital input module, 8 channelsPLC_MOD_DI8 | MODULE_TYPE = Digital inputADDRESS_START = I0.0CHANNELS = 8SIGNAL = 24 V DC | |
| SB1 | Emergency stop (normally closed) to inputPLC_FIELD_ESTOP | ADDRESS = I0.0 | DESCRIPTION = Emergency stop, normally closedCABLE = 2x0.75 mm2 |
| SB2 | Normally closed contact to inputPLC_FIELD_CONTACT_NC | ADDRESS = I0.1 | DESCRIPTION = Stop, normally closedCABLE = 2x0.75 mm2 |
| SB3 | Pushbutton (normally open) to inputPLC_FIELD_PUSHBUTTON | ADDRESS = I0.2 | DESCRIPTION = Start, normally openCABLE = 2x0.75 mm2 |
| FR1 | Normally closed contact to inputPLC_FIELD_CONTACT_NC | ADDRESS = I0.3 | DESCRIPTION = Pump overload, normally closedCABLE = 2x0.75 mm2 |
| 2 | Digital output module, 8 relay outputsPLC_MOD_DO8_RELAY | MODULE_TYPE = Digital output, relayADDRESS_START = Q0.0CHANNELS = 8SIGNAL = 24 V DC, 2 A | |
| KM1 | Relay or contactor coil from outputPLC_FIELD_COIL | ADDRESS = Q0.4 | DESCRIPTION = Pump contactor coilCABLE = 2x0.75 mm2 |
| HL1 | Pilot lamp from outputPLC_FIELD_LAMP | ADDRESS = Q0.5 | DESCRIPTION = Run lamp, greenCABLE = 2x0.75 mm2 |
| HL2 | Pilot lamp from outputPLC_FIELD_LAMP | ADDRESS = Q0.6 | DESCRIPTION = Alarm lamp, redCABLE = 2x0.75 mm2 |
| YV1 | Solenoid valve from outputPLC_FIELD_SOLENOID | ADDRESS = Q0.7 | DESCRIPTION = Inlet valve solenoidCABLE = 2x0.75 mm2 |
| 3 | Analog input module, 4 channels (4-20 mA / 0-10 V)PLC_MOD_AI4 | MODULE_TYPE = Analogue inputADDRESS_START = IW0CHANNELS = 4SIGNAL = 4-20 mA | |
| PT101 | Transmitter, 2-wire 4-20 mA loop to analog inputPLC_FIELD_4_20MA_2WIRE | ADDRESS = IW0 | DESCRIPTION = Discharge pressure transmitterCABLE = 2x0.75 mm2, shielded |
| LT101 | Transmitter, 2-wire 4-20 mA loop to analog inputPLC_FIELD_4_20MA_2WIRE | ADDRESS = IW1 | DESCRIPTION = Wet well level transmitterCABLE = 2x0.75 mm2, shielded |
| PS | Power supply module, 24 VDCPLC_MOD_PSU | INPUT = 230 V ACOUTPUT = 24 V DC, 10 A | |
| 0 | CPU modulePLC_MOD_CPU | MODULE_TYPE = CPU |
Manufacturer, model and remarks are left empty on every block, ready for your data. The values are examples.
How to use it
- Open the sample drawing to see how layers, text and the title block are used, or open it in the browser first, nothing to install.
- Start your own drawing from the template (NEW, then pick the DWT file). Copy the CTB file to your plot styles folder if you want black-and-white plots.
- Insert blocks from the symbol library into your drawing. The blocks in the sample are copies; they do not change when a library changes.
- Double-click the title block to fill it in, then export the equipment list with BlockSync.
Frequently asked questions
- Can I use the drawing for a real project?
- As a starting point for layout and layers, yes. The ratings, settings and cable sizes are made up, so the diagram has to be checked and changed for your project before it is used for design or construction.
- Why are the layers coloured?
- Colours and line weights follow the layers: power circuits are red and heavy, control is cyan, signal is green. The plot style table in the ZIP prints everything black and keeps the line weights, so you can plot in black and white as well.
- Which CAD programs open it?
- The drawing and the template are in AutoCAD 2018 format, which AutoCAD 2018 and later open, and so do other CAD programs that read this format. The browser viewer needs nothing installed.