Air-Insulated RMU vs Gas-Insulated RMU

Direct answer: An air-insulated RMU uses air clearance for the primary insulation system, while a gas-insulated RMU encloses the primary circuit in a sealed insulation chamber. Gas-insulated designs are generally more compact and less exposed to the external environment; air-insulated designs offer familiar access and may suit projects with sufficient room.

Technical Comparison

FactorOption / Requirement AOption / Requirement B
FootprintGenerally largerGenerally compact
Primary circuitMore exposed to room conditionsEnclosed in sealed insulation chamber
Maintenance accessDirect access may be simplerPrimary circuit access is more controlled
Typical selectionClean rooms and cost-sensitive projectsRestricted space, humidity, dust and project standard requirements

Selection Checklist

  • Confirm the nominal and highest system voltage.
  • Confirm rated current, short-time withstand current, peak withstand current and fault duration.
  • Map every feeder and functional unit from the SLD.
  • Review protection, metering, auxiliary supply and remote-control requirements.
  • Check altitude, temperature, humidity, pollution, corrosion and installation conditions.
  • Define GA, SLD, wiring, datasheet, FAT and handover-document requirements.

Qiangchi Product Options

Qiangchi supplies project-configured medium-voltage equipment including QCL-12 RMU, QCL-24 GIS, QCL-40.5 GIS, XGN15 air-insulated RMU and YB compact substation. Rated current options include 630A, 1250A, 2500A and 3150A where applicable to the selected product and approved configuration.

Engineering Workflow

  1. Receive SLD, BOQ and specification.
  2. Review ratings, functional units and interfaces.
  3. Issue technical proposal and clarification list.
  4. Prepare project-specific GA and supporting documents.
  5. Confirm inspection, routine tests and FAT scope.
  6. Complete export packing and shipment documentation.

Frequently Asked Questions

Can I request a budgetary proposal without a final SLD?

Yes. A preliminary proposal can be prepared from available project information, with open items clearly marked for confirmation.

Can the configuration be customized?

Configuration can be evaluated according to the SLD, protection philosophy and actual product capability.

Are dimensions standard?

Dimensions depend on voltage, functional units, cable interfaces and options. Use the project GA drawing.

What service conditions must be stated?

State temperature, altitude, humidity, pollution, corrosion, indoor/outdoor installation and any seismic requirement.

Can Qiangchi support FAT?

Yes. The agreed FAT and witness scope is confirmed before inspection.

What prevents quotation delays?

A clear SLD, system data, quantity, application, destination and document list allow faster technical review.

Request a Project-Specific Proposal

Upload SLD / Specification   Use Product Finder   WhatsApp Engineer

Compare Air-Insulated and Gas-Insulated RMU

AIS and GIS choices should be based on installation space, environment, maintenance strategy, lifecycle expectations, voltage, current and project specification.

RMU & GIS Products · MV Switchgear · Selection Guides · Downloads · Request a Quote · WhatsApp Engineering Team

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