CMRD4845 Equivalent & Substitute Parts

Part Overview

The CMRD4845 is a Solid State Relay (SSR) manufactured by Sensata-Crydom, designed as a SPST-NO (1 Form A) switching device with integrated heat sink for DIN Rail mounting. This component operates with a 4–32VDC input signal and controls AC loads from 48V to 530V at 45A capacity, utilizing zero-cross switching technology for AC applications.

The CMRD4845 maintains Active product status and is fully compliant with ROHS3 and REACH regulations. Substitute parts become necessary when inventory constraints occur, when legacy designs require component refresh, or when application requirements align with alternative qualified models from the same manufacturer family.

Substiute Parts

CMRD4845

Sensata-CrydomIn Stock: 846CMRD4845 Datasheet

Current PartRFQ

GNR45DHZ

Sensata-CrydomIn Stock: 1278GNR45DHZ Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the CMRD4845 is determined by the following critical parameters:

• Circuit Configuration: Must maintain SPST-NO (1 Form A) topology for direct functional replacement
• Input Voltage Range: Must accept 4–32VDC control signal
• Load Current Rating: Must support minimum 45A continuous current
• Output Type: Must provide AC switching with zero-cross capability
• Mounting Interface: Must support DIN Rail installation with screw terminal connections
• Voltage Tolerance: Load voltage range must encompass or exceed the 48–530V operating window

The GNR45DHZ qualifies as a direct substitute based on these parameters. Both devices share identical input voltage specifications, load current capacity, circuit topology, output switching characteristics, and mounting configuration. The GNR45DHZ extends the maximum load voltage to 600V, providing enhanced voltage margin while maintaining full backward compatibility with CMRD4845 applications.

Parameter Comparison

Engineering Selection Recommendations

For Active Design Programs: The CMRD4845 is the primary selection. It maintains Active product status, ensuring long-term availability and manufacturer support. ROHS3 compliance aligns with current regulatory requirements and future-proofs designs against evolving environmental standards.

For Inventory Substitution or Legacy System Maintenance: The GNR45DHZ provides functional equivalence across all critical electrical parameters. The extended load voltage range (48–600V versus 48–530V) presents no compatibility risk and offers additional operational margin. However, the GNR45DHZ carries "Not For New Designs" status, indicating Sensata-Crydom's transition away from this model line. The package form factor difference (Module versus Integrated Heat Sink) requires verification of thermal management adequacy in the specific application context.

Compliance Consideration: Both parts meet REACH and EAR99 export classification requirements. The CMRD4845's ROHS3 compliance supersedes the GNR45DHZ's RoHS compliance for applications subject to the latest environmental directives.

Frequently Asked Questions (FAQ)

Q: Can GNR45DHZ directly replace CMRD4845 in existing installations?

A: Electrical substitution is valid. Both devices share identical input voltage (4–32VDC), load current (45A), circuit topology (SPST-NO), and switching characteristics (AC, zero-cross). Screw terminal connections and DIN Rail mounting are identical. The GNR45DHZ's higher maximum load voltage (600V) does not create incompatibility. Physical form factor differs (Module versus Integrated Heat Sink); verify mounting space and thermal dissipation requirements in your specific application.

Q: Why does GNR45DHZ have "Not For New Designs" status?

A: This designation indicates the manufacturer has discontinued active development and marketing of the GNR series in favor of the CMRD series. New designs should specify CMRD4845 to ensure long-term component availability and manufacturer technical support.

Q: Are there compliance differences between these parts?

A: Both parts comply with REACH and EAR99 regulations. CMRD4845 meets ROHS3 (current standard), while GNR45DHZ meets RoHS (earlier standard). For applications requiring ROHS3 certification, CMRD4845 is the appropriate choice.

Q: What is the significance of the package type difference?

A: CMRD4845 includes an integrated heat sink as part of the SSR assembly, providing passive thermal management. GNR45DHZ is supplied as a module without integrated heat sink. Thermal performance in your application depends on ambient temperature, duty cycle, and available mounting surface area. Consult thermal specifications if substituting into space-constrained or high-ambient-temperature environments.

Q: Can I use GNR45DHZ in applications requiring ROHS3 compliance?

A: GNR45DHZ meets RoHS compliance but does not carry ROHS3 certification. If your application or customer requirements mandate ROHS3, use CMRD4845.