PRMA1C24 Reed Relay Equivalent & Substitute Parts

Part Overview

The PRMA1C24 is a reed relay manufactured by Coto Technology, designed for switching applications requiring 250 mA contact current at 24 VDC coil voltage. This component features a single-pole double-throw (SPDT) contact configuration with through-hole PC pin termination. The PRMA1C24 is classified as obsolete, necessitating identification of active equivalent parts for new designs and ongoing production requirements. Substitute parts must maintain functional compatibility across coil voltage, contact rating, contact form, and termination style while meeting current compliance standards.

Substiute Parts

PRMA1C24

Coto TechnologyIn Stock: 1137PRMA1C24 Datasheet

Current PartRFQ

HE721C2400

Littelfuse Inc.In Stock: 1223HE721C2400 Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the PRMA1C24 are identified based on strict electrical and mechanical compatibility criteria. The following parameters must match or exceed the main part specifications:

Critical Matching Parameters:

• Coil voltage: 24 VDC
• Contact form: SPDT (1 Form C)
• Contact rating: 250 mA minimum
• Mounting type: Through Hole
• Termination style: PC Pin
• Coil type: Non Latching

Allowable Variations:

• Switching voltage: Substitute may exceed maximum rating
• Coil current: Minor variations acceptable within design tolerance
• Operate/Release time: Variations acceptable if within application requirements
• Operating temperature range: Substitute may exceed upper limit
• Coil resistance: Variations acceptable within design tolerance
• Product status: Active parts preferred for obsolete originals

The HE721C2400 from Littelfuse Inc. satisfies all critical matching parameters and is classified as active, making it a direct functional equivalent for the obsolete PRMA1C24.

Parameter Comparison

Engineering Selection Recommendations

The HE721C2400 from Littelfuse Inc. is the direct functional equivalent for the obsolete PRMA1C24. Selection of this substitute is based on the following engineering criteria:

Electrical Compatibility: Both parts operate at 24 VDC coil voltage with identical SPDT contact configuration and 250 mA contact rating. The HE721C2400 provides higher maximum switching voltage (175 VDC versus 100 VDC), which extends application flexibility without compromising performance in existing circuits designed for the PRMA1C24.

Mechanical Compatibility: Both parts feature through-hole mounting with PC pin termination, ensuring direct board-level compatibility without redesign.

Compliance Status: The HE721C2400 maintains ROHS3 compliance and REACH unaffected status, meeting current regulatory requirements. Both parts share identical ECCN and HTSUS classifications.

Product Availability: The HE721C2400 is classified as active with 1211 units in stock, ensuring long-term supply continuity compared to the obsolete PRMA1C24.

Operational Parameters: The HE721C2400 operates across an extended temperature range (-40°C to 85°C versus -40°C to 80°C) and features a lower must-operate voltage (16 VDC versus 18 VDC), providing improved performance margins in low-voltage conditions.

Frequently Asked Questions (FAQ)

Q: Can the HE721C2400 be used as a direct replacement for the PRMA1C24 without circuit modification?

A: Yes. Both parts share identical coil voltage (24 VDC), contact form (SPDT), contact rating (250 mA), mounting type (through-hole), and termination style (PC pin). No circuit modification is required for functional substitution.

Q: What is the significance of the higher switching voltage rating on the HE721C2400?

A: The HE721C2400 supports 175 VDC maximum switching voltage compared to 100 VDC on the PRMA1C24. This higher rating provides additional design margin for applications operating at elevated switching voltages and does not negatively impact performance in circuits designed for the lower rating.

Q: Are there differences in switching speed between these parts?

A: The HE721C2400 has a slightly longer operate time (3 ms versus 2 ms on the PRMA1C24), while release time remains identical at 3 ms. Applications with strict timing requirements below 3 ms operate time should evaluate this parameter against specific circuit requirements.

Q: Do both parts meet current environmental compliance standards?

A: Yes. The HE721C2400 is ROHS3 compliant and REACH unaffected. The PRMA1C24, though obsolete, is RoHS compliant. Both parts carry EAR99 ECCN classification and identical HTSUS codes.

Q: What is the packaging difference between these parts?

A: The PRMA1C24 is supplied in standard packaging, while the HE721C2400 is packaged in tubes. Tube packaging is standard for active production parts and does not affect component functionality or board-level performance.

Q: Is the coil resistance difference between 2.15 kOhms and 2 kOhms significant?

A: The 0.15 kOhm difference represents approximately 7% variation and falls within normal manufacturing tolerance for relay coils. Both parts operate at 24 VDC with coil currents of 11.2 mA and 12 mA respectively, indicating compatible drive circuit requirements.

Q: Can the HE721C2400 operate in the full temperature range of the PRMA1C24?

A: Yes. The HE721C2400 operates across -40°C to 85°C, which exceeds the PRMA1C24 range of -40°C to 80°C. The substitute part maintains performance across the entire original operating range and extends the upper limit by 5°C.