UB5C-33RF1 Equivalent & Substitute Parts

Part Overview

The UB5C-33RF1 is a 33 Ohm, ±1% tolerance, 5W axial wirewound resistor manufactured by Riedon. This through-hole component is designed for current sensing applications and features flame-proof, moisture-resistant, and pulse-withstanding characteristics. The part is currently active in production with 1055 units in stock. Equivalent parts are identified when they maintain identical electrical specifications and mechanical compatibility for direct circuit board substitution.

Substiute Parts

UB5C-33RF1

RiedonIn Stock: 1155UB5C-33RF1 Datasheet

Current PartRFQ

45F33RE

OhmiteIn Stock: 185945F33RE Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

The 45F33RE from Ohmite qualifies as a direct substitute for the UB5C-33RF1 based on the following critical parameters:

• Resistance value: 33 Ohms (identical)
• Tolerance: ±1% (identical)
• Power rating: 5W (identical)
• Composition: Wirewound (identical)
• Package: Axial (identical)
• Temperature coefficient: ±20ppm/°C (identical)
• Moisture sensitivity: MSL 1 (identical)
• RoHS compliance: Both parts meet regulatory requirements

Physical dimensions differ between the two parts, which may affect board layout but does not impact electrical performance or functional compatibility in standard through-hole applications.

Parameter Comparison

Engineering Selection Recommendations

Both the UB5C-33RF1 and 45F33RE are active production parts with full RoHS compliance and MSL 1 moisture sensitivity ratings. The 45F33RE offers an extended maximum operating temperature of 275°C compared to the UB5C-33RF1 at 250°C, providing additional thermal margin in high-temperature applications. Physical dimensions differ; the 45F33RE is larger in both diameter and length, requiring verification of available board space before substitution. Both parts meet ECCN EAR99 export classification requirements.

Frequently Asked Questions (FAQ)

Q: Can the 45F33RE replace the UB5C-33RF1 in all applications?

A: Yes, from an electrical standpoint. Both parts share identical resistance, tolerance, power rating, temperature coefficient, and composition. Physical dimensions differ, so board layout compatibility must be confirmed before installation.

Q: What is the primary difference between these two parts?

A: The main differences are physical size and maximum operating temperature. The 45F33RE is larger (0.343" Dia x 0.937" L versus 0.250" Dia x 0.500" L) and rated to 275°C maximum versus 250°C for the UB5C-33RF1.

Q: Are both parts RoHS compliant?

A: Yes. The UB5C-33RF1 is ROHS3 compliant, and the 45F33RE is RoHS compliant. Both meet regulatory requirements for lead-free manufacturing.

Q: Does the larger size of the 45F33RE affect electrical performance?

A: No. Physical dimensions do not alter the electrical characteristics. The larger size is a manufacturing design difference between Riedon and Ohmite but does not impact resistance value, tolerance, power dissipation, or temperature coefficient.

Q: What is MSL 1 moisture sensitivity?

A: MSL 1 indicates unlimited shelf life with no moisture sensitivity restrictions. Both parts can be stored and handled without special moisture control measures.