Switchboard Drafting Input & Output Specification
Shan Electrical Engineering Ltd — Version 1.0
1. Company Overview
Shan Electrical Engineering Ltd provides professional Switchboard Drafting services for electrical contractors, panel builders, and consulting engineers.
Our responsibility is to convert an engineer's Design Intent into a complete set of manufacturing drawings that can be used by the switchboard manufacturer and installation electricians.
The workflow is:
Design Intent
↓
Drafting
↓
Manufacturing Drawings
↓
Switchboard Manufacturing
↓
Installation
2. Input Document List
The following documents are normally provided by the client before drafting begins.
2.1 Design Specification
Purpose — Defines the engineering requirements of the project.
Typical Format
Project:
Small Retail Shop
Supply:
400V 3 Phase 50Hz
Main Switch:
63A 4 Pole MCCB
Board Type:
Wall Mounted
IP Rating:
IP42
Cable Entry:
Top Entry
Typical Contents
- Project Name
- Supply Voltage
- Frequency
- Main Protection
- Board Type
- Environmental Rating
- Applicable Standards
2.2 Single Line Diagram (SLD)
Purpose — Describes the electrical logic of the switchboard.
Example
Incoming Supply
|
63A MCCB
|
-----------------------
| | |
20A 32A 25A
Light Power HVAC
Typical Contents
- Incoming Supply
- Main Switch
- Busbar
- Circuit Breakers
- Loads
2.3 Equipment Schedule
Purpose — Lists all electrical equipment to be used.
Example
| Item | Manufacturer | Model |
|---|---|---|
| Main MCCB | Schneider | EZC100 |
| MCB | Schneider | Acti9 |
| RCBO | Schneider | Acti9 RCBO |
Typical Contents
- Manufacturer
- Part Number
- Rating
- Quantity
2.4 Load Schedule
Purpose — Lists all outgoing circuits.
Example
| Circuit | Load | Protection |
|---|---|---|
| Lighting | LED Lighting | 20A MCB |
| General Power | Socket Outlets | 32A RCBO |
| HVAC | Air Conditioner | 25A MCB |
2.5 Site Information
Purpose — Defines installation constraints.
Example
Location:
Retail Shop
Mounting:
Wall Mounted
Cable Entry:
Top
Maximum Board Width:
800 mm
Maximum Height:
1200 mm
2.6 Applicable Standards
Purpose — Specifies which electrical standards shall be followed.
Example
AS/NZS 3000
AS/NZS 61439
Customer Specification
3. Output Document List
After drafting is completed, Shan Electrical Engineering Ltd delivers the following documents.
3.1 Single Line Diagram
Purpose — Shows the electrical functional relationship.
Typical Output
Incoming
|
63A MCCB
|
Busbar
|
-----------------------
| | |
20A 32A 25A
3.2 General Arrangement Drawing (GA)
Purpose — Shows the external dimensions and cabinet layout.
Typical Contents
- Cabinet Width
- Cabinet Height
- Cabinet Depth
- Door Layout
- Panel Sections
3.3 Internal Layout Drawing
Purpose — Shows the location of all internal components.
Typical Contents
- MCCB Position
- MCB Position
- DIN Rails
- Busbars
- Terminal Blocks
3.4 Manufacturing Drawing
Purpose — Provides detailed fabrication information.
Typical Contents
- Door Cut-outs
- Mounting Hole Locations
- Busbar Dimensions
- Cable Entry Plate
- DIN Rail Dimensions
3.5 Wiring Diagram
Purpose — Defines all internal wiring connections.
Typical Contents
- Terminal Numbers
- Wire Numbers
- Wire Destination
- Device Connections
3.6 Bill of Materials (BOM)
Purpose — Lists every component required to build the switchboard.
Example
| Qty | Description | Model |
|---|---|---|
| 1 | 63A MCCB | Schneider EZC100 |
| 2 | 20A MCB | Acti9 |
| 1 | 32A RCBO | Acti9 |
3.7 Cable Schedule
Purpose — Defines incoming and outgoing cable information.
Typical Contents
- Cable Number
- Size
- From
- To
- Remarks
4. Deliverables
The complete project package normally contains:
01_Single_Line_Diagram.pdf
02_General_Arrangement.pdf
03_Internal_Layout.pdf
04_Manufacturing_Drawing.pdf
05_Wiring_Diagram.pdf
06_BOM.xlsx
07_Cable_Schedule.xlsx
Next: Case Study: A Small Retail Shop applies this specification to a complete project.