S312 Solid State Relay SPST-NO Module

Part Overview

The S312 is a solid state relay (SSR) module manufactured by Sensata-Crydom, configured as a single-pole single-throw normally open (SPST-NO) switch with a 3A load capacity. This through-hole mounted module operates with a 4.6–8VDC input and supports AC loads from 20V to 140V with zero-cross switching capability.

The S312 is classified as obsolete. Identifying equivalent substitute parts is necessary to maintain system functionality and ensure continued availability for replacement and new designs.

Substiute Parts

S312

Sensata-CrydomIn Stock: 1241S312 Datasheet

Current PartRFQ

LR600240D25

Sensata-CrydomIn Stock: 3197LR600240D25 Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the S312 is determined by the following critical parameters:

• Circuit Configuration: Must remain SPST-NO (1 Form A) to maintain identical switching logic
• Output Type: Must support AC with zero-cross switching for compatible load control
• Mounting Type: Must be through-hole to fit existing PCB layouts
• Termination Style: Must use PC Pin termination for direct board connection
• Package / Case: Must be module form factor

The LR600240D25 satisfies these core substitution criteria. While this part exhibits higher current capacity (25A vs. 3A) and extended voltage ranges, it maintains functional compatibility through identical circuit topology, output switching characteristics, and physical mounting specifications. The elevated ratings provide design margin and do not prevent substitution in applications requiring the S312's baseline performance envelope.

Parameter Comparison

Engineering Selection Recommendations

The S312 is obsolete and no longer in active production. The LR600240D25 is the designated substitute, manufactured by the same supplier and classified as active with current production status.

The LR600240D25 is RoHS3 compliant and REACH affected, providing enhanced environmental and regulatory alignment compared to the S312. Both parts carry identical moisture sensitivity ratings and EAR99 export classification.

Selection of the LR600240D25 ensures access to an actively manufactured component with equivalent functional topology and superior availability for both replacement and new design applications.

Frequently Asked Questions (FAQ)

Q: Can the LR600240D25 directly replace the S312 in existing designs?

A: Yes. Both parts share identical circuit configuration (SPST-NO), output switching type (AC, zero-cross), mounting method (through-hole), and termination style (PC pin). The LR600240D25 operates within the S312's input voltage range (4.6–8VDC falls within 4–32VDC) and load voltage range (20–140V falls within 24–280V). The higher current rating (25A vs. 3A) does not prevent substitution.

Q: What are the key differences between these parts?

A: The LR600240D25 provides higher load current capacity (25A vs. 3A), extended input voltage range (4–32VDC vs. 4.6–8VDC), and extended load voltage range (24–280V vs. 20–140V). The LR600240D25 is active production with RoHS3 compliance, while the S312 is obsolete.

Q: Are there any package or mounting considerations?

A: Both parts use through-hole mounting with PC pin termination in module form factor. No PCB layout modifications are required for substitution.

Q: What compliance differences exist between these parts?

A: The LR600240D25 is RoHS3 compliant and REACH affected. The S312 is REACH unaffected. Both carry identical moisture sensitivity ratings (MSL 1) and EAR99 export classification.