FBMOV115M Equivalent & Substitute Parts

Part Overview

The FBMOV115M is a 180 V varistor manufactured by Littelfuse Inc., designed for transient voltage suppression in single-circuit applications. This component features a 40 kA surge current rating, axial cylindrical packaging, and screw mount configuration. The product is classified as obsolete, making identification of functionally equivalent alternatives necessary for ongoing system maintenance and new design implementations where similar protection characteristics are required.

Substiute Parts

FBMOV115M

Littelfuse Inc.In Stock: 1231FBMOV115M Datasheet

Current PartRFQ

LST1505VL2NT1

Littelfuse Inc.In Stock: 911LST1505VL2NT1 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the FBMOV115M is based on the following critical parameters that define functional equivalence:

• Voltage Protection Rating: The varistor voltage (180 V typical) and maximum continuous operating voltage (150 V DC) establish the protection threshold. Substitute parts must maintain voltage protection within the same operational band.
• Surge Current Capacity: The 40 kA surge rating defines the component's ability to handle transient events. Equivalent parts must meet or exceed this specification.
• Single-Circuit Configuration: The FBMOV115M protects one circuit. Substitutes must maintain single-pole or single-circuit topology.
• Thermal Protection: Both the main part and substitute feature thermally protected designs, a critical safety characteristic.
• Compliance Standards: RoHS3 compliance and regulatory certifications (ECCN, HTSUS codes) must be maintained.

The LST1505VL2NT1 qualifies as a manufacturer-recommended substitute based on these parameters, despite differences in packaging and mounting configuration.

Parameter Comparison

Engineering Selection Recommendations

The LST1505VL2NT1 is the manufacturer-recommended substitute for the obsolete FBMOV115M. Both components are manufactured by Littelfuse Inc. and maintain ROHS3 compliance. The substitute is currently in active production status with 896 units in stock, ensuring availability for replacement and new applications.

The LST1505VL2NT1 operates within the same voltage protection band (150 V maximum continuous operating voltage) as the original part. The substitute features a higher short-circuit rating (200 kA) compared to the original surge rating (40 kA), providing enhanced protection capability. The operating temperature range of the substitute (-40°C to 85°C) is narrower at the lower bound compared to the original (-55°C to 85°C), which may require evaluation in applications requiring extended low-temperature operation.

Both components feature thermally protected designs and maintain single-circuit configurations. The primary differences lie in packaging (tray vs. unspecified for original), mounting type (through hole vs. screw mount), and form factor (module only for substitute). These differences necessitate mechanical redesign considerations in applications where the original screw mount configuration was integral to the assembly.

Frequently Asked Questions (FAQ)

Q: Can the LST1505VL2NT1 directly replace the FBMOV115M without circuit modification?

A: The LST1505VL2NT1 provides equivalent voltage protection and thermal safety characteristics. However, the mounting type differs (through hole vs. screw mount), requiring mechanical redesign of the mounting interface. Electrical functionality is compatible within the specified voltage and current parameters.

Q: What is the significance of the different surge current ratings (40 kA vs. 20 kA discharge)?

A: The FBMOV115M specifies 40 kA surge capacity, while the LST1505VL2NT1 specifies 20 kA discharge current (8/20µS waveform). The LST1505VL2NT1 compensates with a 200 kA short-circuit rating. These represent different measurement methodologies for transient protection capability. Application-specific surge profiles must be evaluated against both specifications.

Q: Are there temperature range limitations when substituting?

A: The LST1505VL2NT1 operates from -40°C to 85°C, compared to the original -55°C to 85°C range. Applications requiring operation below -40°C require alternative solutions or thermal management considerations.

Q: What compliance certifications apply to both parts?

A: Both the FBMOV115M and LST1505VL2NT1 are ROHS3 compliant. Both carry ECCN classification EAR99. The LST1505VL2NT1 includes UL approval agency certification and REACH unaffected status.

Q: Why is the original part classified as obsolete?

A: The FBMOV115M is obsolete, indicating discontinued production by the manufacturer. The LST1505VL2NT1, as an active product from the same manufacturer, represents the current technology platform for equivalent protection requirements.