Direct answer: SF6 RMUs use sulfur hexafluoride as the insulation and/or switching medium, while SF6-free RMUs use alternatives such as dry air, nitrogen-based gas, vacuum switching or solid insulation. The correct choice depends on project specification, environmental policy, availability, voltage class, footprint and lifecycle requirements.
Technical Comparison
| Factor | Option / Requirement A | Option / Requirement B |
|---|---|---|
| Technology maturity | Widely established in MV distribution | Growing range of alternative platforms |
| Environmental consideration | Requires controlled gas handling | Designed to reduce or avoid SF6 use |
| Project acceptance | Common in many existing specifications | Often driven by utility or sustainability requirements |
| Final choice | Confirm local rules and project standard | Confirm approved technology and service support |
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
- Receive SLD, BOQ and specification.
- Review ratings, functional units and interfaces.
- Issue technical proposal and clarification list.
- Prepare project-specific GA and supporting documents.
- Confirm inspection, routine tests and FAT scope.
- 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
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