Sourcing Guide
What Information Do I Need to Source Medium-Voltage Switchgear?
You do not need a complete engineering package to begin sourcing medium-voltage switchgear.
Send what you already have. The most useful starting inputs are company and contact, what the project is, when you need it, where it ships, whether this is a new project or an existing / replacement / expansion situation, a one-line diagram, nameplate photos, overall equipment photos, and any ratings you already know. Incomplete information is normal. GridGear can begin from a partial package and fill gaps as the search progresses.
On the switchgear quote form, contact and project basics are required, and type is required on the form. Technical ratings help when you have them; blank ratings do not block the request.
New project vs existing gear
How the search runs depends on whether you are specifying new gear or matching what is already there. Greenfield searches can often start broader. Replacement and expansion searches usually need tighter matching earlier.
If this is a new or greenfield project
Send:
- Equipment type if known — or say you are not sure. See What Are the Different Types of Switchgear? and GridGear’s switchgear page.
- System voltage and/or voltage class
- Main bus or continuous-current rating
- Interrupting or short-circuit rating if known (use the wording on a nameplate or drawing; do not guess a single “kA” figure)
- Indoor vs outdoor / enclosure preference
- When it is needed and where it ships
- Acceptable condition — for example new surplus / unused, remanufactured, used, or any condition that fits
- Known configuration preferences (main + feeders, main-tie-main, manufacturer family) if you have them
Quantity, outage windows, crane limits, and a hard ship-by date also shape the search. If schedule is the binding constraint, say so. Partial technical information plus a hard date is often more actionable than a perfect spec with no timing.
If this is existing, replacement, or expansion work
The goal is often matching and physical fit, not only a similar ampere rating. Identifying what is already there usually matters as much as the ratings themselves. A one-line is often the single most useful document for these inquiries, alongside nameplates and photos. Existing manufacturer, family, drawings, and cubicle or section identity are often as useful as the electrical numbers.
Prioritize, in roughly this order:
- One-line diagram — actual system voltage, main/tie/feeder arrangement, adjacent transformer or generator sources
- Assembly / lineup nameplate
- Overall lineup photos (full front, section labels, cable entry if safely visible)
- Breaker or primary switching-device nameplate
- Shop drawings or lineup / as-built drawings
- Existing manufacturer, family, and model
- Known ratings and must-match constraints (enclosure, indoor/outdoor construction, bus material, control power, cable entry, arc-resistant class)
For metal-clad lineups, breaker family and model usually matter. Metal-enclosed gear often uses a different primary switching-device family — load-interrupter, vacuum interrupter, or similar — so do not treat those as the same device list as metal-clad breakers.
Replacement-breaker requests also need cubicle / cell identity and racking clues. Electrical ratings alone rarely prove physical compatibility.
Expansions into an existing lineup need drawings and manufacturer/family identity early. Adjacent-section geometry, bus rating and transitions, and section dimensions matter as much as nameplate ratings.
If you have existing gear and need help reading nameplates, one-lines, and drawings, see How to Identify Existing Switchgear: Nameplates, One-Lines, and Drawings.
Documents and photos
If ratings are incomplete or unknown, upload what you have: one-line, nameplates, photos, shop or lineup drawings, an old quote, or existing manufacturer / model / family / serial or project numbers. You do not need every document. A readable one-line, nameplate, or drawing may be enough to begin a useful sourcing conversation, depending on the requirement. Do not guess missing values — send the photo or drawing instead. More complete packages make matching faster and reduce false starts later, especially for replacement or expansion work.
| What you send | What it usually helps with |
|---|---|
| One-line diagram | Actual system voltage, main/tie/feeder arrangement, adjacent sources, transfer context |
| Assembly / lineup nameplate | Manufacturer, voltage class, bus / continuous current, short-circuit rating, construction clues, serial / project identity |
| Overall equipment photos | Metal-clad vs metal-enclosed clues, indoor/outdoor, section layout, modifications, physical constraints |
| Breaker or device nameplate | Breaker or switch model, continuous and interrupting ratings, control / coil voltage clues, technology family |
| Shop / lineup drawings | Section widths, bus transitions, cable entry, throat interfaces, cubicle arrangement, expansion fit |
| Old quote or spec sheet | Original ratings language, preferred options, must-match constraints |
| Existing manufacturer / model / family | Historical drawings, design family, matching or expansion comparison |
| Cubicle / racking / cell info (breakers) | Physical compatibility beyond electrical ratings |
Buyers often start with a one-line and a needed-by date, a nameplate photo without a typed interrupting rating, photos of an existing lineup without drawings, or a replacement-breaker request with the cubicle manufacturer but incomplete coil voltages. Those packages can be enough to begin.
Technical details that help when known
Technical ratings improve match quality, but they are not a mandatory checklist.
Voltage class is not always the same as actual operating voltage. A lineup may be 15 kV class while operating on 12.47 kV, 13.2 kV, or 13.8 kV. Capture both when known. BIL or other insulation-withstand information can also matter when it is shown on the plate or drawing.
Interrupting / short-circuit detail, lineup configuration, drawings, and manufacturer/family identity often matter more for replacement or expansion work than for an early greenfield search. GridGear can often begin without them if they are unknown.
For medium-voltage gear specifically:
- Metal-clad: lineup shape, section count, and breaker identity (drawout breaker family / ratings)
- Metal-enclosed: primary switching-device family (for example fused load-interrupter vs vacuum interrupter) — a different taxonomy than metal-clad breakers
- Pad-mounted: number of ways, insulation medium, and radial vs loop configuration
- Replacement breakers: cubicle / cell fit, racking style, and whether you need an OEM spare, retrofit, or retrofill path
Later diligence — relay/metering packages, control-power and coil voltages, cable-entry direction, bus material, arc-resistant class, feeder schedules, and detailed cubicle-fit dimensions — strengthens evaluation as options appear. It is not required to open an RFQ.
For broader switchgear categories, see What Are the Different Types of Switchgear?.
Need help sourcing medium-voltage switchgear?
Send what you have. A one-line, nameplate photos, lineup drawings, equipment photos, an old quote, or a short list of known ratings is often enough for GridGear to narrow the search.
GridGear helps project teams source medium-voltage switchgear and related power-distribution equipment across new surplus, unused, remanufactured, and used equipment markets when factory lead times, obsolete gear, or matching constraints stall the project.
Technical References
This resource is GridGear-authored educational content informed by industry standards such as IEEE C37.20.2, C37.20.3, C37.74, and C37.04. Standards define equipment and rating structures more precisely than this sourcing guide. Formal engineering, protection, installation, compatibility, and procurement decisions should use the applicable project specifications, drawings, standards, manufacturer data, and qualified technical review.