MERSEN FUSE 6,9 URD 31 D11 A 0800 6,9URD31D11A0800

High-speed Protistor® fuse for semiconductor protection with integrated striker indication and DIN 110 blades, rated for 800A at 690VAC IEC / 700VAC UL.

SKU: H300709Alt SKU: PC31UD69V800D1AMPN: H300709

List Price £207.21 ex VAT

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Why Choose the Mersen H300709 Protistor® High-Speed Fuse?

The Mersen H300709 (Catalogue No. PC31UD69V800D1A) is a Protistor® Size 31 aR square body high-speed semiconductor fuse designed to protect sensitive power electronic devices. Rated at 800A, 690VAC (IEC) and 700VAC (UL), it delivers ultra-fast fault interruption for demanding industrial power conversion applications.

Manufactured by Mersen, the H300709 features a ceramic square body, silver-plated DIN 110 blade terminals and an integrated striker indicator. Its low let-through energy (I²t) and high breaking capacity provide outstanding protection for IGBTs, thyristors, diodes and other semiconductor devices used in modern power electronics.

The Protistor® Size 31 range has been engineered for industrial drives, UPS systems, renewable energy converters, battery storage systems and other equipment requiring reliable semiconductor protection with minimal downtime.

Key Advantages

Genuine Mersen Protistor® semiconductor protection fuse.
Ultra-fast aR operating characteristic.
800A continuous current rating.
690VAC IEC / 700VAC UL voltage rating.
Integrated striker indicator for remote signalling.
DIN 110 silver-plated blade terminals.
High interrupting capacity for industrial applications.
Designed specifically for semiconductor protection.

Key Features

Manufacturer: Mersen
Series: Protistor® Size 31 aR
Manufacturer Part Number: H300709
Catalogue Number: PC31UD69V800D1A
Square body high-speed semiconductor fuse.
Ceramic body with solidified sand arc-quenching technology.
Silver-plated DIN 110 blade terminals.
Integrated striker indicator.
Designed for worldwide industrial power conversion equipment.

Optimised Protection for Semiconductor Equipment

The Mersen H300709 has been specifically engineered to minimise fault energy reaching expensive semiconductor devices. Its ultra-fast aR operating characteristic rapidly clears short-circuit faults while maintaining excellent protection for IGBTs, thyristors, diodes and other power semiconductor components used in industrial converters and drives.

Typical Applications

Variable speed drives.
Industrial inverters.
UPS systems.
Battery energy storage systems.
Solar and wind power converters.
Semiconductor protection circuits.
Industrial power conversion equipment.
DC and AC converter systems.

Technical Specifications

Item number	H300709
Catalogue No	PC31UD69V800D1A
Description	Square Body High-Speed Fuse Protistor® Size 31 aR 690VAC IEC 700VAC UL 800A With Striker DIN 110 Blades
EAN/UPC Code	3605340332513
Rated voltage AC UL	700 V
Rated voltage AC IEC	690 V
Ampere Rating	800 A
RoHS Compliant	Yes
AC or DC	AC
Speed/Characteristic	aR
Fuse Size	31
Mounting	Bolted
Clearing I2t At Rated Voltage	880000 A²s
Melting I2t	140000 A²s
AC Max I.R./Breaking Capacity	I1: 200 kA
Indication System	Yes
Indication System Type	Striker
Connection/Terminal Material	Silver-Plated Copper
Connection/Terminal Type	DIN 110 Blades
Product Width	51 mm
Product Length	134.6 mm
Product Height	56.5 mm
Sell Pack Quantity	3 EA
Sell Pack Weight	1.2429 kg
Sell Pack Width	142 mm
Sell Pack Length	166 mm
Sell Pack Height	62 mm
Product group	Semiconductor Protection Fuses
Body/Insulating Material	Ceramic
Product Weight	0.4143 kg
Power Dissipation at Rated Current Value	120 W
HS Code	85361090
Country of Manufacture	France
Fuse Type	Semiconductor
Fuse Class	aR
Voltage	690 V

Frequently Asked Questions

What is the Mersen H300709 used for?

The H300709 is a Protistor® high-speed semiconductor fuse designed to protect IGBTs, thyristors, diodes and other sensitive semiconductor devices used in industrial power conversion equipment.

What are the voltage ratings?

The fuse is rated at 690VAC according to IEC standards and 700VAC according to UL standards.

What is the current rating?

The Mersen H300709 has a continuous current rating of 800A.

Does the fuse include an indicator?

Yes. The H300709 includes an integrated striker indicator for remote fuse operation signalling.

What type of terminals does it use?

This model features DIN 110 silver-plated blade terminals for secure bolted installation.

Trusted by Power Electronics Professionals

Mersen Protistor® semiconductor fuses are trusted worldwide by equipment manufacturers, electrical engineers and maintenance professionals for protecting high-value power electronic equipment in demanding industrial applications.

Item number	H300709
Catalogue No	PC31UD69V800D1A
Description	Square Body High-Speed Fuse Protistor® Size 31 aR 690VAC IEC 700VAC UL 800A With Striker DIN 110 Blades
EAN/UPC Code	3605340332513
Rated voltage AC UL	700 V
Rated voltage AC IEC	690 V
Ampere Rating	800 A
RoHS Compliant	Yes
AC or DC	AC
Speed/Characteristic	aR
Fuse Size	31
Mounting	Bolted
Clearing I2t At Rated Voltage	880000 A²s
Melting I2t	140000 A²s
AC Max I.R./Breaking Capacity	I1: 200 kA
Indication System	Yes
Indication System Type	Striker
Connection/Terminal Material	Silver-Plated Copper
Connection/Terminal Type	DIN 110 Blades
Product Width	51 mm
Product Length	134.6 mm
Product Height	56.5 mm
Sell Pack Quantity	3 EA
Sell Pack Weight	1.2429 kg
Sell Pack Width	142 mm
Sell Pack Length	166 mm
Sell Pack Height	62 mm
Product group	Semiconductor Protection Fuses
Body/Insulating Material	Ceramic
Product Weight	0.4143 kg
Power Dissipation at Rated Current Value	120 W
HS Code	85361090
Country of Manufacture	France
Fuse Type	Semiconductor
Fuse Class	aR
Voltage	690 V

UK delivery

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