Isolator
Disconnector
A switching device providing an electrical isolation function.
SLD / Schematic
Functional block · DMII
Disconnector motor-control isolation interface
Functional block · Switchyards
An independently authored application reference. The drawing shows the named function or circuit relationship; use the project legend and selected equipment documentation for its drafting form and connections.
Browse this installation focusIn plain English
What this block does
Marks the assigned separation of the electric drive control supply.
A simple example
In a switchyard bay, a bus selector can use a different physical construction from a line disconnector. Each device still needs an identified operating mechanism, position indication and interlocking interface. For this reference, the drawing identifies “Drive supply isolation device” at the input and “Motor-control isolation boundary” at the output. Control isolation does not establish primary isolation.
What the drawings help you do
Start at the named input: Drive supply isolation device. Identify its source device or document and the state represented on the drawing. Follow the named output: Motor-control isolation boundary. Cross-reference its destination and separate the command from confirmation that the equipment responded.
- Input
- Drive supply isolation device
- Output
- Motor-control isolation boundary
- Application reference
- An explanation of a named drawing function or circuit relationship; the project documents define the equipment and its connections.
Read the source: Disconnectors and earthing switches
Schematic · DMII
What it represents
Marks the assigned separation of the electric drive control supply. Disconnector and earthing references identify different mechanical constructions and connection duties within a yard. The primary diagram shows which conductors are joined or earthed; the equipment drawing explains how its contacts and supports move.
In a switchyard bay, a bus selector can use a different physical construction from a line disconnector. Each device still needs an identified operating mechanism, position indication and interlocking interface. For this reference, the drawing identifies “Drive supply isolation device” at the input and “Motor-control isolation boundary” at the output. Control isolation does not establish primary isolation.
The construction name does not establish load-breaking capability, short-circuit making duty or operating permission. Verify these properties in the selected equipment data and the station interlocking scheme. The functional block is an independent explanation of this named application. Equipment-specific ratings, terminal connections and operating conditions must be established in the project documentation.
How to read it
- Start at the named input: Drive supply isolation device. Identify its source device or document and the state represented on the drawing.
- Follow the named output: Motor-control isolation boundary. Cross-reference its destination and separate the command from confirmation that the equipment responded.
- Control isolation does not establish primary isolation.
- The construction name does not establish load-breaking capability, short-circuit making duty or operating permission. Verify these properties in the selected equipment data and the station interlocking scheme.
Information to show or reference
- Label the source and connection reference for drive supply isolation device.
- Identify the destination and defined state of motor-control isolation boundary.
- Record the equipment or control-document revision supporting this functional block.
- Check this application limit in the project design: Control isolation does not establish primary isolation.
A distinction that matters
Control isolation does not establish primary isolation. This reference describes the named application; it does not establish a new IEC graphical symbol, an ANSI device-function number or an exact manufacturer connection diagram.
Sources you can follow
These public references support the explanation and provide further detail. Their graphics and downloadable files remain with their publishers.
Disconnectors and earthing switches
Public technical context for disconnector and earthing applications. Disconnector construction, earthing switches and operating mechanisms. The application text and educational graphic are independently authored; the publisher does not certify this representation.
About this graphic
This illustration was authored independently by Elora Grid to explain the concept. It is not reproduced from a customer drawing, an official standard graphic or a manufacturer CAD file. Its correspondence to an exact IEC or IEEE symbol identifier has not been certified.
SVG and DXF downloads contain this original artwork. Original artwork is available under CC BY 4.0. Third-party references retain their own terms.
Explore related references
Put the reference into a drawing workflow.
Elora Grid helps electrical teams work with drawings, specifications and equipment information. Explore the drafting workflow or join the early-access waitlist.