Disconnect switch selection selection starts with the circuit role, the project requirement, and selected-model documentation. Disconnect Switch Selection Questions for Panel Builders helps panel builders organize those checks before a device is specified or an RFQ is issued. Isolation duty is owned by the single-line diagram and the selected disconnect documentation, not by a catalog thumbnail.
Part 1. What isolation question is the disconnect switch answering?
A disconnect switch is reviewed when the design needs a documented means to isolate a circuit for service or switching under the project rules. The first task is to name the circuit, the isolation location, and the duty expected from the selected product documentation.
Part 2. Which circuit and location inputs belong on the drawing?
Record supply arrangement, load side boundary, number of poles, presence of neutral, enclosure location, operator access, and any interlocking with doors or upstream devices. These inputs prevent treating a miniature isolator as a universal substitute for another isolation method.
The following review table keeps assumptions out of the drawing and quotation stage:
| Check | Why the panel team needs it | Do not assume |
|—|—|—|
| Circuit role | Defines the protection or control question | A category image proves the installed duty |
| Selected-model documents | Confirm terminals, functions, and limits | A generic product family confirms every option |
| Project rules | Set the applicable design and acceptance context | One regional practice is a global default |
| Drawing revision | Keeps the panel and RFQ aligned | An earlier schematic still represents the build |
Part 3. How should utilization and switching duty be framed in the RFQ?
Ask for the utilization category, load type, and switching expectations to be confirmed against the selected model. Do not assume that every isolating switch is suitable for every make/break duty shown on a marketing page.
Important: A disconnect device must be selected for its documented isolation duty; catalogue photos do not prove padlocking, utilization category, or safe isolation for a specific circuit. (source — IEC switch-disconnector standards discovery)
Part 4. Where do locking and service procedures interact with selection?
If the project requires padlocking or lockout interfaces, state that requirement explicitly and verify it in the selected-model instructions. Procedure ownership stays with the site safety plan; the product only supplies the documented mechanical interface.
Part 5. What should buyers put in a disconnect-switch RFQ?
Include the single-line diagram, isolation point, pole arrangement, environmental context, requested documentation, branding needs, and the exact evidence the supplier must return for the proposed model.
A compact RFQ input list makes the supplier response easier to compare:
| Buyer should provide | Why it matters | Common mistake |
|---|---|---|
| Current drawing set | Defines the circuit boundary | Sending a product name without a diagram |
| Required functions | Makes the request reviewable | Treating unverified options as standard |
| Installation context | Identifies project conditions to confirm | Assuming category copy is a project approval |
| Documentation request | Connects the RFQ to exact evidence | Accepting generic claims instead of model data |
| Send with quote | Makes supplier comparison auditable | Quoting without the requested evidence pack |
For broader context, review the disconnect switch selection product family and the related product line page.
Part 6. Which CHAC product route is the right starting point?
The CQD2 miniature isolating switch product route supports early discussion for control-circuit isolation after inputs are listed, while the isolating-switch category provides family navigation. Neither page authorizes a project isolation scheme by itself.
Product recommendation
Use the published relevant CHAC product page as a documented product route starting point for a product discussion only after the RFQ inputs are complete. OEM labeling for isolating switches can be raised on the terminal-electrical customization page. A compact isolator silhouette does not prove padlocking, utilization category, or conductor scope for the isolation point.
Part 7. Where does disconnect-switch RFQ guidance stop?
Use this guide for RFQ preparation and early panel isolation scoping. It is not a lockout/tagout procedure, a DC PV isolator guide, or a claim that one CHAC model matches every feeder or motor circuit. Schedule a drawing review that marks the isolation boundary and any door interlocks before purchasing.
Fit Boundary: disconnect RFQ scoping stops short of lockout/tagout procedures and DC PV isolator decisions.
Related reading: a narrower, already-published CHAC article is linked for context, not as a replacement for this article’s decision scope.
Bring the isolation point and pole arrangement to contact CHAC Electric when you need an isolating-switch product route.
FAQs
Is every isolating switch suitable for load breaking?
No. Switching and isolation duties are model-specific and must be confirmed in the selected documentation.
What drawing defines the isolation point?
The approved single-line diagram and panel layout define where isolation is required and which conductors are included.
Can a miniature isolator replace a larger feeder disconnect by appearance?
No. Circuit role, ratings evidence, and project rules control the choice.
When should padlocking be listed in the RFQ?
List it whenever the project safety plan requires a lockable isolation interface, then verify the selected model supports that interface.
Which documents should a supplier return?
Return the proposed model identification plus the installation and performance documents requested in the RFQ.
How does this differ from a DC PV isolator review?
DC PV and battery isolation has different circuit and product-route questions; keep that review on its own project inputs.
