PRMA1C05 Reed Relay SPDT 250mA 5V - Equivalent & Substitute Parts

Part Overview

The PRMA1C05 is a reed relay manufactured by Coto Technology, configured as a Single Pole Double Throw (SPDT) contact form with 250mA contact rating and 5VDC coil voltage. This product is classified as obsolete, necessitating identification of functionally equivalent active substitute components for continued system design and maintenance applications. Equivalent parts must maintain identical electrical specifications across coil voltage, contact form, contact current rating, and coil resistance while accommodating allowable variations in switching voltage, timing characteristics, and operating temperature ranges.

Substiute Parts

PRMA1C05

Coto TechnologyIn Stock: 3151PRMA1C05 Datasheet

Current PartRFQ

DIP05-1C90-51L

Standex-Meder ElectronicsIn Stock: 1067DIP05-1C90-51L Datasheet

SimilarRFQ

HE721C0500

LittelfuseIn Stock: 1364HE721C0500 Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the PRMA1C05 are identified based on the following critical parameters that must match or exceed the original specification:

Primary Matching Criteria (Must Be Identical):

• Coil Voltage: 5VDC
• Contact Form: SPDT (1 Form C)
• Contact Rating (Current): 250 mA
• Coil Current: 25 mA
• Coil Type: Non Latching
• Coil Resistance: 200 Ohms
• Termination Style: PC Pin
• Mounting Type: Through Hole

Secondary Compatibility Parameters (Allowable Variations):

• Switching Voltage: Substitute parts may exceed the original 100VAC/100VDC rating
• Operating Temperature: Substitute parts may provide broader temperature ranges
• Operate/Release Time: Variations acceptable within switching application requirements
• Must Operate/Release Voltage: Substitute parts with lower thresholds provide improved sensitivity

Both identified substitutes (DIP05-1C90-51L and HE721C0500) satisfy all primary matching criteria, with enhanced switching voltage ratings and active product status.

Parameter Comparison

Engineering Selection Recommendations

Both DIP05-1C90-51L (Standex-Meder Electronics) and HE721C0500 (Littelfuse) are active, production-available substitutes for the obsolete PRMA1C05. Selection between these alternatives depends on specific application requirements:

DIP05-1C90-51L: Offers superior switching voltage rating (175VAC/175VDC), faster operation (0.7 ms operate, 1.5 ms release), and compliance with ROHS3 standards. Operating temperature range (-20°C to 70°C) is narrower than the original specification.

HE721C0500: Provides extended operating temperature range (-40°C to 85°C) matching or exceeding the original PRMA1C05 specification. The part exhibits the lowest must-release voltage (0.5 VDC), enhancing sensitivity in low-voltage switching applications. ROHS3 compliance and 175VDC switching voltage rating are supported.

Both substitutes are REACH unaffected and classified under ECCN EAR99, maintaining equivalent regulatory compliance with the original component.

Frequently Asked Questions (FAQ)

Q: Are DIP05-1C90-51L and HE721C0500 direct pin-compatible replacements for PRMA1C05?

A: Yes. Both substitutes maintain identical contact form (SPDT), termination style (PC Pin), and mounting type (Through Hole) as the original PRMA1C05. Component pinout compatibility is preserved for direct board-level substitution without mechanical or electrical interface modifications.

Q: What is the significance of the switching voltage difference between the original and substitute parts?

A: The PRMA1C05 supports 100VAC and 100VDC maximum switching voltage. Both substitutes (DIP05-1C90-51L and HE721C0500) support 175VDC maximum switching voltage, exceeding the original specification. This enhancement provides greater safety margin in high-voltage switching applications. Applications operating below 100VDC experience no functional change.

Q: How do the operate and release times differ between options?

A: The DIP05-1C90-51L exhibits faster response (0.7 ms operate, 1.5 ms release) compared to the PRMA1C05 (2 ms operate, 3 ms release). The HE721C0500 matches the original timing (3 ms release) with slightly longer operate time (3 ms). Application-specific timing requirements determine whether the faster DIP05 variant or timing-matched HE721 variant is appropriate.

Q: Does the operating temperature range affect substitution suitability?

A: The DIP05-1C90-51L operates within -20°C to 70°C, which is narrower than the original -40°C to 80°C range. This substitution is suitable only for applications not requiring operation below -20°C or above 70°C. The HE721C0500 (-40°C to 85°C) fully encompasses the original temperature specification and is preferred for wide-temperature-range applications.

Q: What is the packaging impact on component procurement?

A: Both substitutes are supplied in tube packaging, whereas the original PRMA1C05 packaging is not specified. Tube packaging is standard for through-hole reed relays and presents no compatibility issues for automated or manual assembly processes.

Q: Are both substitutes available in equivalent inventory quantities?

A: The DIP05-1C90-51L (1044 Pcs) and HE721C0500 (1300 Pcs) are both maintained in production inventory. Component availability differs from the PRMA1C05 (3129 Pcs), reflecting its obsolete status. Current inventory levels support standard procurement timelines for both active substitutes.