Two medium-voltage switchgear inquiries can have the same voltage requirement and still need different equipment arrangements. A clear inquiry describes the electrical duties, the operating arrangement and the installation interfaces together.
Define the function of each panel
Use a single-line diagram and a panel schedule to show incoming feeders, outgoing feeders, transformer circuits, metering and any bus-section arrangement. Identify the purpose of each panel rather than relying on a general request for a set of switchgear.
CANGO’s catalog includes several medium-voltage equipment families. The appropriate family depends on the project requirements; a model name alone does not define every panel’s components and functions.
Keep the ratings separate
Rated voltage, normal current and short-circuit duties describe different requirements. Record the values required by the project engineer or utility, including the relevant duration where a short-time withstand rating is specified. Do not use a normal-current value as a substitute for fault-duty information. Manufacturer switchgear comparisons list these as separate characteristics; see ABB’s air-insulated switchgear overview for general background.
Confirm control and protection interfaces
State the required auxiliary supply, metering, protection and communication interfaces. If specific relays or components are required, include the project specification. Identify which settings, studies and site interfaces are supplied by the project team and which documents are expected from the equipment supplier.
Include physical constraints
- Indoor or outdoor installation and the available equipment-room layout.
- Cable entry direction and the available termination space.
- Operating and maintenance access requirements.
- Existing equipment interfaces for an extension or replacement.
- Environmental and enclosure requirements stated in the project specification.
For a retrofit, photographs are useful alongside dimensions, existing drawings and nameplate information. They help explain the installation, but should not replace verified technical data.
Agree what the quotation includes
Ask for a defined panel list, equipment configuration, document list and stated exclusions. Any provisional item should be visible in the quotation. This makes it easier to compare offers and resolve differences before production planning.
Browse CANGO medium-voltage switchgear and our retrofit and expansion guide. For a real installation reference, see the Tianjin Chengxi distribution renovation project.
