SINOFUSE RS309-MM Series AC/DC 1000V Stud-Mounted High-Speed Fuse
The SINOFUSE RS309-MM Series is a stud-mounted high-speed fuse family designed for demanding AC and DC electrical protection applications. The series is rated at AC/DC 1000V and covers a broad current range from 5A to 800A.
According to the SINOFUSE manufacturer specification, RS309-MM fuses use the aR protection category and combine compact construction, low I²t characteristics, high breaking capacity, and strong resistance to vibration and demanding operating environments.
RS309-MM Series Technical Specifications
- Manufacturer: SINOFUSE
- Series: RS309-MM
- Product Type: Stud-mounted high-speed fuse
- Rated Voltage: AC/DC 1000V
- Rated Current Range: 5A to 800A
- Protection Category: aR
- AC Breaking Capacity: 100kA
- DC Breaking Capacity: 50kA
- DC Time Constant: ≤15ms
- Performance Standard: IEC 60269
- Safety / Environmental Reliability Reference: ISO 8820
- Certification: CE
- Environmental Compliance: RoHS
Key Features
- Compact stud-mounted construction
- Low I²t characteristics
- High breaking capacity
- Designed for demanding AC and DC applications
- Strong resistance to vibration
- Suitable for vehicle and industrial power environments
Typical Applications
According to the manufacturer datasheet, the RS309-MM Series can be used in applications including:
- Electric vehicle traction systems
- Power converters
- Energy storage systems
- Charging equipment
- Industrial power systems
- Short-circuit protection
- Overload protection
- Backup protection
RS309-MM Model Range
The RS309-MM family includes 28 rated-current options from 5A to 800A across multiple mechanical size groups.
| Size Code | Current Range | Available Ratings | Mounting Bolt | Recommended Torque |
|---|---|---|---|---|
| 2YA | 5A–30A | 5A, 10A, 15A, 20A, 25A, 30A | M6 | 6 ±1 N·m |
| 4RC | 35A–80A | 35A, 40A, 50A, 60A, 70A, 80A | M8 | 12 ±1 N·m |
| 5RB | 90A–175A | 90A, 100A, 125A, 150A, 175A | M8 | 12 ±1 N·m |
| 6RB | 200A–300A | 200A, 225A, 250A, 300A | M10 | 21 ±1 N·m |
| 7HA | 350A–600A | 350A, 400A, 450A, 500A, 600A | M10 | 21 ±1 N·m |
| 8HA | 700A–800A | 700A, 800A | M13 | 35 ±1 N·m |
Complete RS309-MM Current Ratings
Available RS309-MM ratings include:
5A, 10A, 15A, 20A, 25A, 30A, 35A, 40A, 50A, 60A, 70A, 80A, 90A, 100A, 125A, 150A, 175A, 200A, 225A, 250A, 300A, 350A, 400A, 450A, 500A, 600A, 700A and 800A.
Electrical Performance Data
The manufacturer provides pre-arcing I²t, total clearing I²t, and power-loss data for each RS309-MM current rating. These values vary by model and should be reviewed when selecting a fuse for power-electronic or high-current applications.
The manufacturer notes that the published test data were obtained under DC test conditions, with circuitry referenced to IEC 60269 / UL 248 test arrangements.
Continuous Current Recommendation
According to the manufacturer specification, the recommended long-term operating current is approximately 80% of the fuse rated current under normal operating conditions.
Applications outside the normal environmental conditions may require current correction or additional application evaluation.
Operating Conditions
- Normal Ambient Temperature: -5°C to 40°C
- Permitted Ambient Temperature: -40°C to 85°C
- Product Storage Temperature: -40°C to 120°C
- Normal Operating Altitude: Below 2000m
- Permitted Altitude: 2000m to 4500m with correction where required
- Pollution Class: Grade 3
High-Altitude Applications
The manufacturer notes that higher altitude affects thermal performance, air pressure, and insulation strength. In enclosed installations where internal temperature remains elevated, rated-current derating may be required.
For applicable enclosed installations, the datasheet indicates a current derating guideline of approximately 2% to 5% for every 1000m increase in altitude.
Vibration and Mechanical Resistance
The RS309-MM Series is designed for demanding vibration environments. The manufacturer references GB2423.10-2008 4.1.2.6 and QC/T 413-2002 for vibration performance.
The series is also specified as conforming to rail-transport vibration Grade II and suitable for vehicle operating conditions.
Installation Considerations
The manufacturer specifies that electrical contacts must be securely connected and that contact resistance should not adversely affect fuse operation.
RS309-MM fuses may be mounted in different orientations, provided that the mounting arrangement maintains reliable electrical contact and avoids adverse effects from gravity or vibration.
Browse RS309-MM Models
Apexon Supply provides the complete RS309-MM 5A–800A range through a single multi-variant product page:
View SINOFUSE RS309-MM AC/DC 1000V 5A–800A Fuse Options
Related SINOFUSE Resources
- SINOFUSE Fuse Solutions – Brand & Technical Overview
- SINOFUSE RS309-MD Series AC/DC 500V High-Speed Bolt-Connected Fuse
- SINOFUSE RS309-MF Series 700V/750V High-Speed Bolt-Mounted Fuse
Technical Sourcing Support
Apexon Supply supports industrial buyers with SINOFUSE product identification, specification review, model selection, technical cross-reference, and international sourcing coordination.
For RS309-MM availability, technical information, or quotation requests, please provide the required current rating, quantity, and available application details.