RT500AS3R30JB Equivalent & Substitute Parts

Part Overview

The RT500AS3R30JB is a 3.3 Ohm, 500W wirewound linear potentiometer manufactured by Vishay Sfernice, designed for panel mount applications with a 1-turn adjustment mechanism and solder turret termination. This component is classified as obsolete, necessitating identification of active equivalent parts to maintain design continuity and ensure supply chain availability for new production and maintenance applications.

Substiute Parts

RT500AS3R30JB

Vishay SferniceIn Stock: 826RT500AS3R30JB Datasheet

Current PartRFQ

RRS3R0E

OhmiteIn Stock: 747RRS3R0E Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the RT500AS3R30JB is based on the following critical parameters that define functional equivalence:

• Resistance Value: Substitute parts must operate within the tolerance band of the original specification. The RT500AS3R30JB specifies 3.3 Ohms ±5%. The RRS3R0E provides 3 Ohms ±10%, representing a 0.3 Ohm nominal difference within acceptable tolerance overlap for high-power resistive applications.
• Power Rating: Both parts must support 500W continuous operation to maintain thermal and electrical performance in the application circuit.
• Taper Characteristic: Linear taper is required to preserve the adjustment response curve of the original design.
• Construction Type: Wirewound construction is mandatory for 500W power dissipation capability and thermal stability.
• Mounting Configuration: Panel mount with single-gang, single-turn adjustment defines the mechanical interface requirement.

The RRS3R0E from Ohmite meets these core substitution criteria and is classified as an active product, providing supply continuity for the obsolete RT500AS3R30JB.

Parameter Comparison

Engineering Selection Recommendations

The RRS3R0E is the designated manufacturer-recommended substitute for the RT500AS3R30JB. Selection of this part is supported by the following factors:

• Product Status: The RRS3R0E maintains active production status, ensuring long-term availability and supply chain reliability compared to the obsolete RT500AS3R30JB.
• Compliance: The RRS3R0E is ROHS3 compliant, meeting current environmental and regulatory requirements for electronic component procurement.
• Functional Equivalence: Both parts share identical power rating, taper, construction method, and mounting configuration, establishing direct functional compatibility.
• Resistance Tolerance: The 0.3 Ohm nominal difference between 3.3 Ohms and 3 Ohms falls within the combined tolerance bands of both specifications, permitting direct substitution in applications where the resistance value is not a critical design constraint.

Frequently Asked Questions (FAQ)

Q: Can the RRS3R0E be used as a direct replacement for the RT500AS3R30JB?

A: Yes, the RRS3R0E is the manufacturer-recommended substitute. Both parts share identical power ratings, linear taper, wirewound construction, and panel mount configuration. The 0.3 Ohm resistance difference is within acceptable tolerance overlap for high-power applications.

Q: What is the significance of the resistance tolerance difference between the two parts?

A: The RT500AS3R30JB specifies ±5% tolerance (3.135 to 3.465 Ohms), while the RRS3R0E specifies ±10% tolerance (2.7 to 3.3 Ohms). The tolerance bands overlap, allowing substitution in applications where the nominal resistance value does not require tighter control than ±10%.

Q: Are there mechanical differences that affect installation?

A: Yes. The RRS3R0E has a larger body diameter (203.20 mm vs. 143.00 mm) and uses a flatted actuator instead of a round actuator. The actuator length is slightly longer (50.80 mm vs. 50.00 mm). Panel cutout and mounting bracket compatibility must be verified before installation.

Q: What is the difference between solder turret and solder lug termination?

A: Solder turret termination uses a turret-style connection point, while solder lug termination uses a flat lug. Both are solder-based connections suitable for PCB or chassis mounting. The specific termination style must be compatible with the application's connection method.

Q: Is the RRS3R0E RoHS compliant?

A: Yes, the RRS3R0E is ROHS3 compliant, meeting current environmental regulations. The RT500AS3R30JB compliance status is not specified in the available documentation.

Q: Can I use the RRS3R0E in applications requiring the exact 3.3 Ohm resistance value?

A: The RRS3R0E nominal value is 3 Ohms with ±10% tolerance. If the application requires the exact 3.3 Ohm value with tight tolerance control, the resistance tolerance difference must be evaluated against circuit performance requirements.