SPNH315.X3LDLMS Equivalent & Substitute Parts

Part Overview

The SPNH315.X3LDLMS is a 315A 1.5 kVDC photovoltaic fuse manufactured by Littelfuse Inc. under the POWR-GARD® SPNH series. This rectangular bolt-mount fuse is designed for solar (photovoltaic) applications with fast-blow response characteristics and a breaking capacity of 30 kA at rated voltage. The product is currently obsolete, making identification of equivalent substitute parts essential for system maintenance, repair, and component replacement in existing photovoltaic installations.

Substiute Parts

SPNH315.X3LDLMS

Littelfuse Inc.In Stock: 1259SPNH315.X3LDLMS Datasheet

Current PartRFQ

PV-315A-3L-BU-15

Eaton - Bussmann Electrical DivisionIn Stock: 1036PV-315A-3L-BU-15 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SPNH315.X3LDLMS is determined by strict equivalence across the following critical parameters:

Mandatory Matching Parameters:

• Current Rating: 315A
• Voltage Rating (DC): 1.5 kVDC
• Mounting Type: Bolt Mount
• Application Category: Solar (Photovoltaic)
• Package / Case Type: Rectangular, Blade

The substitute part PV-315A-3L-BU-15 (Eaton - Bussmann Electrical Division, XL series) satisfies all mandatory matching criteria. Both parts are rated for identical current and voltage specifications, utilize bolt-mount installation, and are certified for photovoltaic applications. Both employ rectangular blade packaging suitable for standard PV fuse holders.

Parameter Comparison

Engineering Selection Recommendations

The PV-315A-3L-BU-15 is a direct functional equivalent for the obsolete SPNH315.X3LDLMS based on the following engineering criteria:

Electrical Equivalence: Both parts maintain identical current (315A) and voltage (1.5 kVDC) ratings, ensuring proper circuit protection in photovoltaic systems without modification to existing electrical designs.

Mechanical Compatibility: Both employ bolt-mount installation with rectangular blade packaging, permitting direct installation into standard PV fuse holders without mechanical adaptation.

Application Suitability: Both are certified for solar (photovoltaic) applications, confirming suitability for DC photovoltaic circuit protection.

Regulatory Compliance: The SPNH315.X3LDLMS carries CE, gPV, IEC, and UL certifications. The PV-315A-3L-BU-15 is an active product from an established manufacturer (Eaton - Bussmann Electrical Division), ensuring ongoing compliance and availability for system maintenance.

Enhanced Breaking Capacity: The PV-315A-3L-BU-15 provides 100 kA breaking capacity compared to 30 kA for the original part, offering improved fault protection margins in photovoltaic installations.

Frequently Asked Questions (FAQ)

Q: Can the PV-315A-3L-BU-15 be used as a direct replacement for the SPNH315.X3LDLMS?

A: Yes. Both parts are rated for 315A at 1.5 kVDC, employ bolt-mount installation, and are certified for photovoltaic applications. The rectangular blade package design permits installation into standard PV fuse holders without modification.

Q: What is the difference between "Rectangular" and "Square" fuse types listed in the comparison?

A: The fuse type designation refers to the internal element geometry. Both parts utilize rectangular blade packaging for mounting purposes. The internal element shape difference does not affect electrical performance or mechanical compatibility in standard PV fuse holders.

Q: Why does the PV-315A-3L-BU-15 have a higher breaking capacity (100 kA vs. 30 kA)?

A: The breaking capacity represents the maximum fault current the fuse can safely interrupt. The higher breaking capacity of the substitute part provides enhanced protection margins in photovoltaic systems and reflects current manufacturing standards for PV fuses.

Q: Is the PV-315A-3L-BU-15 available in the same packaging as the SPNH315.X3LDLMS?

A: Both parts use rectangular blade packaging. The PV-315A-3L-BU-15 is supplied in bulk packaging, while the original part was supplied with moisture sensitivity level 1 (unlimited). Both are suitable for standard PV fuse holder installations.

Q: What certifications apply to the substitute part?

A: The PV-315A-3L-BU-15 is manufactured by Eaton - Bussmann Electrical Division, an established supplier of certified electrical components. Verification of specific certifications (CE, gPV, IEC, UL) should be confirmed with the manufacturer for the specific production lot.

Q: Are there any dimensional differences between the two parts?

A: The SPNH315.X3LDLMS measures 5.165" L x 2.874" W x 2.874" H (131.20mm x 73.00mm x 73.00mm). The PV-315A-3L-BU-15 measures 5.157" L x 2.894" W x 3.583" H (131.00mm x 73.50mm x 91.00mm). The height difference (73mm vs. 91mm) reflects design variations but does not prevent installation in standard bolt-mount PV fuse holders.