Equivalent & Substitute Parts for 5SF 800

Part Overview

The 5SF 800 is an 800 mA, 250 V AC/DC fast-blow glass cartridge fuse in 5mm x 20mm package format, manufactured by Bel Fuse Inc. This part is classified as obsolete. Due to its obsolete status, equivalent and parametrically compatible substitute parts from active manufacturers are necessary for ongoing system support and new designs. Substitute parts maintain the same electrical ratings, mechanical form factor, and functional performance while offering improved availability and compliance status.

Key Parameters

Parameter	Value
Current Rating	800 mA
Voltage Rating (AC)	250 V
Fuse Type	Cartridge, Glass
Response Time	Fast Blow
Package / Case	5mm x 20mm
Mounting Type	Requires Holder
Operating Temperature Range	-55°C ~ 125°C
Breaking Capacity @ Rated Voltage	35A (standard series)

Substitute Part Grouping Explanation

Substitution for the 5SF 800 is determined by strict equivalence across the following parameters: current rating (800 mA), voltage rating (250 V AC), fuse type (cartridge glass), response time (fast blow), and mechanical package (5mm x 20mm). All substitute parts listed maintain these core electrical and mechanical specifications, ensuring direct functional compatibility within existing fuse holders.

Substitute parts are grouped into two categories:

Direct Manufacturer Equivalents: Parts from Bel Fuse Inc. (5SF 800-R, 5MF 800-R) that maintain identical electrical performance with improved product status and compliance.

Cross-Manufacturer Equivalents: Parts from Littelfuse Inc., SCHURTER Inc., and Eaton Electronics that meet all core electrical and mechanical parameters while offering active product status and RoHS3 compliance.

Secondary parameters such as melting I²t, DC cold resistance, and breaking capacity may vary within acceptable ranges for the 5mm x 20mm fast-blow cartridge fuse category but do not affect substitutability for standard circuit protection applications.

Parameter Comparison

Part Number	Manufacturer	Current Rating (mA)	Voltage (V AC)	Response Time	Package	Breaking Capacity (A)	Melting I²t	Product Status	RoHS Status
5SF 800	Bel Fuse Inc.	800	250	Fast Blow	5mm x 20mm	35	1.01	Obsolete	Non-compliant
5SF 800-R	Bel Fuse Inc.	800	250	Fast Blow	5mm x 20mm	35	1.0	Active	RoHS3 Compliant
5MF 800-R	Bel Fuse Inc.	800	250	Fast Blow	5mm x 20mm	200	0.4	Active	RoHS3 Compliant
0034.1515	SCHURTER Inc.	800	250	Fast Blow	5mm x 20mm	35	0.508	Active	RoHS3 Compliant
0217.800MXBP	Littelfuse Inc.	800	250	Fast Blow	5mm x 20mm	35	0.85	Active	RoHS3 Compliant
0217.800MXP	Littelfuse Inc.	800	250	Fast Blow	5mm x 20mm	35	0.85	Active	RoHS3 Compliant
0217.800TXP	Littelfuse Inc.	800	250	Fast Blow	5mm x 20mm	35	0.85	Active	RoHS3 Compliant
0217.800VXP	Littelfuse Inc.	800	250	Fast Blow	5mm x 20mm	35	0.85	Active	RoHS3 Compliant
0217.800HXP	Littelfuse Inc.	800	250	Fast Blow	5mm x 20mm	35	0.85	Active	RoHS3 Compliant
0235.800HXP	Littelfuse Inc.	800	250	Fast Blow	5mm x 20mm	35	0.253	Active	RoHS3 Compliant
GDB-800MA	Eaton - Electronics Division	800	250	Fast Blow	5mm x 20mm	35	0.67	Active	RoHS3 Compliant

Engineering Selection Recommendations

Primary Recommendation: 5SF 800-R (Bel Fuse Inc.) is the direct successor to the obsolete 5SF 800. It maintains identical electrical specifications, mechanical form factor, and breaking capacity while offering active product status and RoHS3 compliance. This part provides the lowest risk substitution path for existing designs.

Alternative Selections: Littelfuse 0217.800MXP, 0217.800TXP, and 0217.800VXP are functionally equivalent cross-manufacturer alternatives with active status and comprehensive international certifications (CCC, CE, CSA, SEMKO, UL, VDE). These parts are suitable for new designs and offer broad regulatory approval.

High Breaking Capacity Option: 5MF 800-R (Bel Fuse Inc.) provides 200A breaking capacity compared to the standard 35A, offering enhanced protection margin in applications requiring higher fault current withstand. This part maintains all other electrical parameters and is RoHS3 compliant.

Regulatory Compliance: All recommended substitute parts carry RoHS3 compliance status. The original 5SF 800 is RoHS non-compliant. For applications subject to RoHS requirements, any listed substitute part satisfies compliance obligations.

Frequently Asked Questions (FAQ)

Q: Can I directly replace 5SF 800 with 5SF 800-R in existing equipment?

A: Yes. The 5SF 800-R is the direct active equivalent with identical current rating (800 mA), voltage rating (250 V AC), response time (fast blow), and mechanical package (5mm x 20mm). No circuit modifications are required.

Q: What is the difference between 5SF 800-R and 5MF 800-R?

A: Both maintain 800 mA current rating and 250 V AC voltage rating. The primary difference is breaking capacity: 5SF 800-R provides 35A breaking capacity, while 5MF 800-R provides 200A. The 5MF series is suitable for applications with higher fault current requirements. Melting I²t also differs (1.0 vs. 0.4), affecting response characteristics.

Q: Are Littelfuse 0217 series parts compatible with existing 5SF 800 fuse holders?

A: Yes. All listed substitute parts maintain the 5mm x 20mm mechanical package and cartridge glass form factor. They are mechanically and electrically compatible with standard 5x20mm fuse holders.

Q: What certifications do the substitute parts carry?

A: Littelfuse 0217.800MXP, 0217.800TXP, and 0217.800VXP carry CCC, CE, CSA, SEMKO, UL, and VDE certifications. SCHURTER 0034.1515 carries CCC, cURus, and VDE certifications. Eaton GDB-800MA carries VDE and UR certifications. All are RoHS3 compliant.

Q: Can I use 5MF 800-R as a direct replacement for 5SF 800?

A: Yes, for electrical and mechanical compatibility. However, the 5MF series has different melting I²t (0.4 vs. 1.01) and higher breaking capacity (200A vs. 35A). Verify that your circuit design accommodates these characteristics before substitution.

Q: Which substitute part offers the best availability?

A: 5MF 800-R (Bel Fuse Inc.) shows the highest inventory at 4515 pieces. 0235.800HXP (Littelfuse Inc.) shows 1395 pieces. Both are active products with strong stock levels.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message