SINOFUSE RSZ307-3-RAZ 1500VDC High-Speed Fuse Series, 100A–630A

The SINOFUSE RSZ307-3-RAZ series is a Size 3, bolt-connected high-speed fuse family designed for 1500VDC electrical protection, with rated currents from 100A to 630A.

The series combines a 250kA rated breaking capacity, strong current-limiting characteristics, and multiple current ratings for high-power DC protection requirements.

Apexon Supply provides independent B2B sourcing support for RSZ307-3-RAZ fuses, including model identification, technical specification review, quotation, bulk procurement, and international delivery coordination.

RSZ307-3-RAZ Series Overview

Parameter Specification
Brand SINOFUSE
Series RSZ307-3-RAZ
Product Type High-Speed Square-Body Fuse
Protection Type Partial-Range High-Speed Protection
Rated Voltage 1500VDC
Rated Current Range 100A–630A
Rated Breaking Capacity 250kA
Time Constant ≤5 ms
Size Code 3
Connection Bolt Connected
Recommended Installation Screw fixing with spring washer
Recommended Tightening Torque 11 ± 1 N·m
Performance Reference IEC 60269-4 / UL 248-13
Certifications / Compliance UL, TÜV, RoHS

Model Selection Table

The RSZ307-3-RAZ series includes twelve current ratings from 100A to 630A.

Model Rated Current Rated Voltage Pre-Arcing I²t Total I²t @ 1500VDC Power Loss
RSZ307-3-RAZ-100A1500V 100A 1500VDC 1,090 A²s 5,000 A²s 55W
RSZ307-3-RAZ-125A1500V 125A 1500VDC 1,940 A²s 8,500 A²s 65W
RSZ307-3-RAZ-160A1500V 160A 1500VDC 3,650 A²s 15,800 A²s 83W
RSZ307-3-RAZ-200A1500V 200A 1500VDC 5,900 A²s 25,500 A²s 100W
RSZ307-3-RAZ-250A1500V 250A 1500VDC 10,900 A²s 47,000 A²s 115W
RSZ307-3-RAZ-315A1500V 315A 1500VDC 20,500 A²s 88,000 A²s 133W
RSZ307-3-RAZ-350A1500V 350A 1500VDC 27,380 A²s 120,000 A²s 142W
RSZ307-3-RAZ-400A1500V 400A 1500VDC 39,400 A²s 168,000 A²s 155W
RSZ307-3-RAZ-450A1500V 450A 1500VDC 58,900 A²s 277,500 A²s 160W
RSZ307-3-RAZ-500A1500V 500A 1500VDC 79,100 A²s 373,000 A²s 180W
RSZ307-3-RAZ-550A1500V 550A 1500VDC 105,800 A²s 500,000 A²s 187W
RSZ307-3-RAZ-630A1500V 630A 1500VDC 158,000 A²s 745,000 A²s 214W

The I²t and power-loss values vary significantly across the series. Engineers should therefore verify the exact model rather than treating fuses with similar current ratings as interchangeable.

Understanding I²t Characteristics

High-speed fuse selection involves more than rated voltage and current.

Pre-arcing I²t represents the energy required before the fuse element begins interruption.

Total clearing I²t represents the energy passed through the fuse during the complete interruption process.

These parameters are important when coordinating fuse protection with downstream power-electronic equipment.

As the rated current increases across the RSZ307-3-RAZ family, both pre-arcing I²t and total clearing I²t increase substantially.

For this reason, replacement selection should be based on the complete electrical characteristics of the original fuse and the requirements of the protected system.

High Breaking Capacity for 1500VDC Systems

The RSZ307-3-RAZ series is specified with a 250kA rated breaking capacity at 1500VDC.

High breaking capacity is particularly important in systems capable of producing very high prospective fault currents.

The fuse must interrupt the fault safely while limiting the energy transferred to downstream electrical components.

Square-Body Bolt-Connected Construction

The RSZ307-3-RAZ family uses a Size 3 square-body construction with bolted terminals.

The manufacturer recommends screw fixing with spring washers and a tightening torque of:

11 ± 1 N·m

Correct installation helps maintain reliable electrical contact and reduces unnecessary thermal or mechanical stress at the connection points.

For replacement projects, verify the terminal arrangement and equipment mounting dimensions before installation.

Typical High-Voltage DC Sourcing Applications

Apexon Supply currently supports RSZ307-3-RAZ sourcing for high-power DC protection requirements associated with industrial power electronics.

Typical procurement enquiries include applications involving:

  • High-voltage DC power conversion

  • Energy storage systems

  • Battery power systems

  • DC bus protection

  • Power semiconductor protection

  • High-power inverter systems

  • Charging and power-conversion equipment

  • Industrial DC electrical systems

Final fuse selection should always be based on the electrical design and protection requirements of the specific equipment.

Available RSZ307-3-RAZ Models

Apexon Supply currently supports sourcing for multiple models within the RSZ307-3-RAZ series, including:

RSZ307-3-RAZ-160A1500V
160A, 1500VDC high-speed square-body fuse.

RSZ307-3-RAZ-315A1500V
315A, 1500VDC high-speed square-body fuse.

RSZ307-3-RAZ-350A1500V
350A, 1500VDC high-speed square-body fuse.

RSZ307-3-RAZ-400A1500V
400A, 1500VDC high-speed square-body fuse.

RSZ307-3-RAZ-450A1500V
450A, 1500VDC high-speed square-body fuse.

RSZ307-3-RAZ-500A1500V
500A, 1500VDC high-speed square-body fuse.

RSZ307-3-RAZ-550A1500V
550A, 1500VDC high-speed square-body fuse.

RSZ307-3-RAZ-630A1500V
630A, 1500VDC high-speed square-body fuse.

Additional 100A, 125A, 200A and 250A variants are also included in the manufacturer series specification.

Technical Datasheet

The manufacturer technical documentation provides:

  • Full RSZ307-3-RAZ model-selection table

  • Rated current information

  • Pre-arcing I²t

  • Total clearing I²t

  • Power-loss values

  • Mechanical dimensions

  • Installation configuration

  • Certification and compliance information

Use the technical datasheet together with the complete fuse model number when verifying a replacement.

How to Request an RSZ307-3-RAZ Quote

For faster quotation and technical confirmation, please provide:

  • Complete SINOFUSE part number

  • Required quantity

  • Product label or photo, if available

  • Equipment/application information when replacement verification is required

  • Delivery country

Apexon Supply supports exact-MPN sourcing, datasheet review, technical verification, bulk RFQ, proforma invoicing, and international delivery coordination.