MERSEN FUSE 12,5 URD 73 TT F 0350 12,5URD73TTF0350
High-speed aR fuse rated at 350A for semiconductor protection with flush striker ends and metric thread terminals, suitable for industrial power applications up to 1300VAC.
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Why Choose the Mersen K300504 High-Speed Semiconductor Fuse?
The Mersen K300504 is an industrial high-speed semiconductor fuse intended to protect sensitive power electronic components against damaging short-circuit currents. It is suitable for consideration in systems containing devices such as IGBTs, thyristors and power diodes, where rapid fault interruption and low let-through energy are essential.
High-speed semiconductor fuses operate more rapidly than conventional industrial fuses. When correctly selected, they limit peak fault current and the I²t energy transferred to connected components, helping reduce thermal stress, prevent extensive equipment damage and minimise unplanned production downtime.
The K300504 may be used in industrial drives, converters, rectifiers, uninterruptible power supplies and other power electronic equipment. Publicly accessible manufacturer information for this exact reference could not be reliably verified, so its current rating, voltage rating, operating class, breaking capacity, terminal arrangement and dimensions must be confirmed against the product label or official Mersen documentation before specification or installation.
Key Advantages
High-speed fault protection for sensitive semiconductor components.
Rapid operation helps limit damaging peak current and let-through energy.
Suitable for industrial power-conversion and motor-control equipment.
Helps reduce thermal and electrical stress during short circuits.
Designed for coordination with power semiconductor modules.
Can help minimise equipment damage and costly downtime.
Key Features
Mersen manufacturer reference K300504.
Designed for semiconductor and power electronic protection.
Fast response to high short-circuit currents.
Low energy let-through characteristics.
Industrial fuse construction for demanding installations.
Suitable for use in an appropriately rated mounting arrangement.
Intended for coordinated protection in power-conversion equipment.
Electrical and mechanical ratings must be verified before installation.
Technical Specifications
Manufacturer: Mersen
Model: K300504
Product category: High-speed semiconductor fuse
Protection application: Industrial power electronic equipment
Typical protected components: IGBTs, thyristors and power diodes
Installation environment: Industrial electrical systems
Rated current: Confirm against official Mersen documentation
Rated voltage: Confirm against official Mersen documentation
Operating class: Confirm against official Mersen documentation
Breaking capacity: Confirm against official Mersen documentation
Pre-arcing I²t: Confirm against the official datasheet
Total clearing I²t: Confirm against the official datasheet
Terminal configuration: Confirm against the official product drawing
Dimensions: Confirm against the official product drawing
Selection requirement: Match all electrical and mechanical specifications to the original fuse
Reliable Protection for Industrial Power Electronics
Power semiconductor devices can be permanently damaged by fault energy before a standard circuit-protection device has time to operate. High-speed semiconductor fuses are engineered to interrupt short-circuit currents rapidly, limiting both peak current and the total energy experienced by the protected components.
Correct fuse selection must consider system voltage, continuous and cyclic current, prospective short-circuit current, ambient temperature, cooling conditions, terminal arrangement and the withstand characteristics of the semiconductor module. A replacement fuse should never be selected solely because it has similar physical dimensions.
Typical Applications
Variable-speed and variable-frequency drives.
Industrial AC and DC power converters.
IGBT inverter systems.
Thyristor and diode rectifiers.
Uninterruptible power supplies.
Renewable energy conversion equipment.
Motor control systems.
Industrial automation equipment.
Technical Specifications
Item number
K300504
Catalogue No
PC73UD13C350TF
Description
Square Body High-Speed Fuse Protistor® Size 73 aR 1250VAC IEC 1300VAC UL 350A With Striker Flush ends metric threads
EAN/UPC Code
3605340329445
Rated voltage AC UL
1300 V
Rated voltage AC IEC
1250 V
Ampere Rating
350 A
AC or DC
AC
Speed/Characteristic
aR
Fuse Size
73
Mounting
Bolted
Clearing I2t At Rated Voltage
140 kA²s
Melting I2t
17 kA²s
AC Max I.R./Breaking Capacity
I1: 126 kA
Indication System
Yes
Indication System Type
Striker
Connection/Terminal Material
Silver-Plated Brass
Connection/Terminal Type
Flush ends
Product Width
73 mm
Product Length
74 mm
Product Height
78.5 mm
Sell Pack Quantity
1 EA
Sell Pack Weight
1.22 kg
Sell Pack Width
110 mm
Sell Pack Length
125 mm
Sell Pack Height
75 mm
Product group
Semiconductor Protection Fuses
Body/Insulating Material
Ceramic
Product Weight
1.22 kg
Power Dissipation at Rated Current Value
86 W
HS Code
85351000
Frequently Asked Questions
What is the Mersen K300504 used for?
The Mersen K300504 is intended to provide high-speed fault protection for sensitive semiconductor components used in industrial power electronic equipment.
Which components can a high-speed fuse protect?
A correctly selected high-speed fuse can protect components such as IGBT modules, thyristors and power diodes against damaging short-circuit energy.
What is the current rating of the Mersen K300504?
The current rating for this exact reference could not be reliably verified from publicly accessible manufacturer information. Check the fuse label or official Mersen datasheet before specifying a replacement.
Can the K300504 replace another fuse with the same dimensions?
Not necessarily. The voltage rating, current rating, operating class, breaking capacity, I²t characteristics and terminal arrangement must all meet the equipment requirements.
How should the correct replacement fuse be selected?
Compare the complete manufacturer reference and all electrical and mechanical specifications with the original fuse and the equipment manufacturer's protection requirements.
Trusted Protection for Industrial Power Systems
Mersen high-speed fuses are used in industrial power electronic systems where rapid fault interruption and effective coordination with sensitive semiconductor components are essential.
Item number
K300504
Catalogue No
PC73UD13C350TF
Description
Square Body High-Speed Fuse Protistor® Size 73 aR 1250VAC IEC 1300VAC UL 350A With Striker Flush ends metric threads
EAN/UPC Code
3605340329445
Rated voltage AC UL
1300 V
Rated voltage AC IEC
1250 V
Ampere Rating
350 A
AC or DC
AC
Speed/Characteristic
aR
Fuse Size
73
Mounting
Bolted
Clearing I2t At Rated Voltage
140 kA²s
Melting I2t
17 kA²s
AC Max I.R./Breaking Capacity
I1: 126 kA
Indication System
Yes
Indication System Type
Striker
Connection/Terminal Material
Silver-Plated Brass
Connection/Terminal Type
Flush ends
Product Width
73 mm
Product Length
74 mm
Product Height
78.5 mm
Sell Pack Quantity
1 EA
Sell Pack Weight
1.22 kg
Sell Pack Width
110 mm
Sell Pack Length
125 mm
Sell Pack Height
75 mm
Product group
Semiconductor Protection Fuses
Body/Insulating Material
Ceramic
Product Weight
1.22 kg
Power Dissipation at Rated Current Value
86 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...