Honeywell POS187311 Liquid Level Sensor - Equivalent & Substitute Parts

Part Overview

The Honeywell POS187311 is a liquid level sensor with NPN output configuration, designed for bracket mount installation in industrial liquid level detection applications. This sensor features stainless steel housing and prism materials, operating across a temperature range of -25°C to 100°C with a voltage rating of 12 to 28V DC.

The POS187311 is classified as an obsolete product. Identifying equivalent substitute parts is necessary for system maintenance, repair, and new design implementations where the original component is no longer available through standard distribution channels.

Substiute Parts

POS187311

Honeywell Sensing and Productivity SolutionsIn Stock: 929POS187311 Datasheet

Current PartRFQ

SQ4-A22-N

Panasonic Industrial Automation SalesIn Stock: 743SQ4-A22-N Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the POS187311 are identified based on the following critical parameters that determine functional compatibility:

Primary Compatibility Criteria:

• Output Configuration: NPN (required match)
• Mounting Type: Bracket Mount (required match)
• Sensor Type: Liquid level detection (required match)
• Voltage Rating: Minimum 12V DC support (required match)

Secondary Compatibility Considerations:

• Operating temperature range overlap
• Housing material chemical compatibility
• Current handling capability
• RoHS compliance status

The substitute part SQ4-A22-N from Panasonic Industrial Automation Sales meets the primary compatibility criteria. However, differences exist in operating temperature range, voltage rating maximum, and housing material that must be evaluated for specific application requirements.

Parameter Comparison

Engineering Selection Recommendations

For POS187311 Replacement:

The SQ4-A22-N is an active product from Panasonic Industrial Automation Sales and represents a viable substitute where application parameters align with its specifications. The substitute maintains NPN output configuration and bracket mount design, ensuring mechanical and electrical interface compatibility.

Critical Differences Requiring Application Verification:

1. Operating Temperature Range: The SQ4-A22-N operates from -10°C to 55°C, which is narrower than the POS187311 range of -25°C to 100°C. Applications requiring operation below -10°C or above 55°C cannot use this substitute.

2. Voltage Rating Maximum: The SQ4-A22-N supports 12 to 24V DC, while the POS187311 supports 12 to 28V DC. Systems operating above 24V DC require alternative solutions.

3. Housing Material: The POS187311 uses stainless steel; the SQ4-A22-N uses PFA. Chemical compatibility with the liquid being sensed must be confirmed for the PFA material.

Compliance Status:

Both parts maintain MSL 1 (Unlimited) moisture sensitivity classification and are RoHS compliant. The SQ4-A22-N carries ROHS3 compliance, meeting current regulatory requirements.

Frequently Asked Questions (FAQ)

Q: Can the SQ4-A22-N directly replace the POS187311 in all applications?

A: No. The SQ4-A22-N is a functional substitute only where application operating temperature remains between -10°C and 55°C, system voltage does not exceed 24V DC, and PFA material is chemically compatible with the sensed liquid. Applications outside these parameters require alternative solutions.

Q: What is the significance of the NPN output configuration in substitution?

A: NPN output configuration determines the electrical interface with the control system. Both the POS187311 and SQ4-A22-N use NPN configuration, ensuring compatible signal conditioning and control circuit integration. Substitution with PNP output sensors would require circuit redesign.

Q: Why does the POS187311 have a wider operating temperature range than the SQ4-A22-N?

A: Operating temperature range is determined by component design, material selection, and sensor calibration. The POS187311's -25°C to 100°C range reflects its design specifications. The SQ4-A22-N's -10°C to 55°C range reflects Panasonic's design parameters. These are independent specifications and cannot be modified through substitution.

Q: What does bracket mount mean for these sensors?

A: Bracket mount refers to the mechanical installation method. Both sensors use bracket-based mounting, allowing installation on support structures without threaded connections. This ensures mechanical compatibility between the two parts.

Q: Is the difference in housing material (stainless steel vs. PFA) significant?

A: Yes. Stainless steel and PFA have different chemical resistance properties. The sensed liquid's chemical composition may attack one material but not the other. Application-specific chemical compatibility must be confirmed before substitution.

Q: What does RoHS compliance mean for component selection?

A: RoHS compliance indicates the component meets restrictions on hazardous substances in electrical and electronic equipment. Both parts are RoHS compliant, meeting regulatory requirements for most industrial markets. The SQ4-A22-N's ROHS3 compliance represents the current standard.

Q: Can I use the SQ4-A22-N in a system designed for 28V DC operation?

A: No. The SQ4-A22-N maximum voltage rating is 24V DC. Operating at 28V DC exceeds the component's specification and may cause damage or failure. Alternative parts rated for 28V DC operation must be identified.

Q: What is MSL 1 (Unlimited) moisture sensitivity?

A: MSL 1 (Unlimited) indicates the component has minimal sensitivity to moisture absorption and can be stored without time-limited desiccant packaging. Both the POS187311 and SQ4-A22-N carry this classification, simplifying inventory and storage management.