Direct answer: 630A is the continuous current rating of the relevant main circuit, while 25kA normally indicates the RMS short-time withstand current for a stated duration. They describe different duties and must be confirmed together with peak withstand current and fault duration.
Key Points
- 630A: continuous thermal current capability
- 25kA: short-circuit withstand capability, not normal load current
- Duration: commonly stated separately and must match the specification
- Peak withstand current: associated electrodynamic duty
- Actual feeder load and fault level must be calculated by the project engineer
Selection Guidance
Do not select an RMU only because its current rating exceeds the operating load. Confirm system study results, future expansion, ambient conditions, busbar rating, cable rating and protection clearing time.
Information Required for Engineering Review
Provide the nominal voltage, highest system voltage, rated current, short-circuit level and duration, frequency, application, SLD, BOQ, protection requirements, cable details, installation conditions and quantity. Qiangchi will confirm the project-specific configuration and document requirements.
Engineering Documents and FAT
Available project support may include configuration review, technical clarification, GA drawing, typical SLD coordination, component schedule, routine-test documentation, FAT planning and export packing. Final scope is confirmed according to the approved specification.
Frequently Asked Questions
Can the final selection be made from the voltage and current alone?
No. The SLD, fault level, functional units, protection, cables and service conditions must also be reviewed.
Are all configurations the same size?
No. Dimensions depend on voltage class, functional units, cable arrangement and optional devices. Use the approved GA drawing.
Can Qiangchi review an EPC specification?
Yes. Send the SLD, BOQ and specification for a project-specific technical review.
What is checked during FAT?
The FAT scope may include visual and mechanical checks, wiring verification, interlock checks, functional tests and routine electrical tests according to the agreed inspection plan.
Which standards apply?
The applicable IEC or project standard is confirmed during technical clarification. Project-specific requirements must be stated before design approval.
Where can I compare related products?
Review QCL-12 RMU, technical datasheets or use the Medium Voltage Product Finder.
Send Your SLD for Review
Qiangchi will evaluate the voltage, rated current, fault level, functional units, drawings, testing and delivery documentation.