High-speed aR fuse designed for semiconductor protection with a 630A rating, 1100VAC IEC and 1200VAC UL voltage ratings, featuring a ceramic body, striker indication system, and open slot blades for bolted mounting.
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Why Choose the Mersen R300625 High-Speed Semiconductor Fuse?
The Mersen R300625, catalogue reference PC72UD11C630EF, is a Protistor® Size 72 high-speed semiconductor fuse designed to protect sensitive power-conversion equipment against damaging fault currents. Rated at 630A, the fuse supports operating voltages up to 1100VAC under IEC standards and 1200VAC under UL standards.
Its ultra-fast aR operating characteristic makes the R300625 particularly suitable for protecting power semiconductors such as diodes, thyristors and insulated-gate bipolar transistors. Rapid interruption helps limit the thermal and electrical energy transferred to valuable semiconductor devices during short-circuit conditions.
The fuse features a robust square ceramic body, silver-plated open-slot blade contacts and an integrated striker for fault indication or operation of a compatible microswitch. Its bolted mounting arrangement provides a secure connection in industrial power systems, variable-speed drives, rectifiers, inverters and other high-power electronic equipment.
Key Advantages
Ultra-fast aR fuse characteristic for semiconductor protection.
High 630A current rating for demanding power applications.
Open-slot blade contacts support secure bolted installation.
Low I²t performance helps minimise damage to semiconductor devices.
Robust ceramic construction provides excellent thermal resistance.
Silver-plated contact surfaces support dependable electrical conductivity.
Key Features
Mersen Protistor® Size 72 fuse-link.
Manufacturer part number R300625.
Catalogue number PC72UD11C630EF.
Square-body high-speed semiconductor fuse.
aR partial-range protection characteristic.
Designed for AC electrical systems.
630A rated current.
1100VAC IEC rated voltage.
1200VAC UL rated voltage.
Integrated striker indication system.
Open-slot blade terminal design.
Bolted mounting configuration.
Non-magnetic mounting hardware.
Silver-plated electrical contact surfaces.
Technical Specifications
Manufacturer: Mersen
Product range: Protistor®
Manufacturer part number: R300625
Catalogue number: PC72UD11C630EF
Alternative reference: 11 URD 72 EF 0630
Product type: High-speed semiconductor fuse
Fuse body size: Size 72
Fuse characteristic: aR
Rated current: 630A
Rated voltage under IEC: 1100VAC
Rated voltage under UL: 1200VAC
Current type: AC
Terminal type: Open-slot blades
Mounting method: Bolted mounting
Indicator: Integrated striker
Body material: Ceramic
Contact finish: Silver plated
Power dissipation at rated current: 125W
Approximate product weight: 0.758kg
EAN: 3605340331189
Fast and Reliable Semiconductor Protection
Power semiconductors can be damaged extremely quickly when exposed to excessive current. The Mersen R300625 uses specially engineered fuse elements embedded in solidified sand to control internal arcing and interrupt severe fault currents rapidly. This construction helps deliver low let-through energy and a high interrupting capability.
The fuse is designed for partial-range short-circuit protection and should be coordinated with the equipment’s overload-protection system. Correct fuse selection requires consideration of operating voltage, continuous current, prospective fault current, thermal cycling, cooling conditions and the I²t withstand capability of the protected semiconductor.
Typical Applications
Variable-speed motor drives.
Industrial power converters.
Rectifiers and inverters.
Uninterruptible power supplies.
Battery energy-storage converters.
Industrial heating equipment.
Welding power supplies.
Protection of diodes and thyristors.
Protection of IGBT power modules.
High-power automation equipment.
Technical Specifications
Item number
R300625
Catalogue No
PC72UD11C630EF
Description
Square Body High-Speed Fuse Protistor® Size 72 aR 1100VAC IEC 1200VAC UL 630A With Striker Open Slot Blades
EAN/UPC Code
3605340331189
Rated voltage AC UL
1200 V
Rated voltage AC IEC
1100 V
Ampere Rating
630 A
AC or DC
AC
Speed/Characteristic
aR
Fuse Size
72
Mounting
Bolted
Clearing I2t At Rated Voltage
690 kA²s
Melting I2t
106.3 kA²s
AC Max I.R./Breaking Capacity
I1: 150 kA
Indication System
Yes
Indication System Type
Striker
Connection/Terminal Material
Silver-Plated Copper
Connection/Terminal Type
Open Slot Blades
Product Width
59 mm
Product Length
149.4 mm
Product Height
63 mm
Sell Pack Quantity
3 EA
Sell Pack Weight
2.274 kg
Sell Pack Width
157 mm
Sell Pack Length
205 mm
Sell Pack Height
80 mm
Product group
Semiconductor Protection Fuses
Body/Insulating Material
Ceramic
Product Weight
0.758 kg
Power Dissipation at Rated Current Value
125 W
HS Code
85351000
Frequently Asked Questions
What is the Mersen R300625?
The Mersen R300625 is a 630A Protistor® Size 72 square-body high-speed fuse designed for the short-circuit protection of power semiconductors. Its catalogue reference is PC72UD11C630EF.
What voltage is the Mersen R300625 rated for?
The R300625 is rated for 1100VAC under IEC specifications and 1200VAC under UL specifications.
What does the aR fuse classification mean?
An aR fuse is a partial-range high-speed fuse designed primarily to protect semiconductor devices against short-circuit currents. Separate overload protection may be required within the electrical system.
Which components can the R300625 protect?
The fuse is suitable for protecting power semiconductors including diodes, thyristors and IGBT modules used in drives, rectifiers, inverters and industrial power converters.
Does the R300625 include a fuse indicator?
Yes. The fuse incorporates a striker that provides mechanical indication when the fuse operates and may be used with a compatible microswitch for remote signalling.
How is the Mersen R300625 installed?
The R300625 uses open-slot blade terminals and a bolted mounting arrangement. Installation should be completed by qualified personnel using the specified tightening torque and appropriate electrical safety procedures.
Trusted High-Speed Fuse Technology
Mersen Protistor® fuses are engineered to provide fast, dependable protection for sensitive semiconductor devices used throughout modern industrial power-conversion systems.
Item number
R300625
Catalogue No
PC72UD11C630EF
Description
Square Body High-Speed Fuse Protistor® Size 72 aR 1100VAC IEC 1200VAC UL 630A With Striker Open Slot Blades
EAN/UPC Code
3605340331189
Rated voltage AC UL
1200 V
Rated voltage AC IEC
1100 V
Ampere Rating
630 A
AC or DC
AC
Speed/Characteristic
aR
Fuse Size
72
Mounting
Bolted
Clearing I2t At Rated Voltage
690 kA²s
Melting I2t
106.3 kA²s
AC Max I.R./Breaking Capacity
I1: 150 kA
Indication System
Yes
Indication System Type
Striker
Connection/Terminal Material
Silver-Plated Copper
Connection/Terminal Type
Open Slot Blades
Product Width
59 mm
Product Length
149.4 mm
Product Height
63 mm
Sell Pack Quantity
3 EA
Sell Pack Weight
2.274 kg
Sell Pack Width
157 mm
Sell Pack Length
205 mm
Sell Pack Height
80 mm
Product group
Semiconductor Protection Fuses
Body/Insulating Material
Ceramic
Product Weight
0.758 kg
Power Dissipation at Rated Current Value
125 W
HS Code
85351000
No documents available for this product.
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2025 has been a big year for LED Controls, and our blog has expanded accordingly. We've covered a wide range of topics across industrial control and factory automation this year. From core technology explainers and new product releases to panel building best practice...
2025 has been a big year for LED Controls, and our blog has expanded accordingly. We've covered a wide range of topics across industrial control and factory automation this year. From core technology explainers and new product releases to panel building best practice...