Description

• Model: 2108N4001N
• Brand: Honeywell Analytics
• Series: Searchpoint Optima Plus
• Core Function: Detects flammable ethylene gas concentration
• Type: Point Infrared Flammable Gas Detector
• Key Specs: 0-100% LEL, 4-20 mA output, 24 VDC nominal, ATEX/IECEx

Product Introduction

The HONEYWELL 2108N4001N is a Searchpoint Optima Plus point infrared flammable-gas detector configured specifically for ethylene. It provides a 4-20 mA analog output and is certified for hazardous-area installation under ATEX/IECEx schemes. The detector uses an electro-polished 316 stainless-steel body with an M25 threaded entry, plus a dust barrier, weather housing, and deluge/sunshade.

Its measurement range is 0-100% LEL, with a nominal 24 VDC supply and maximum power consumption below 4.5 W. The infrared design has no catalytic bead, and Honeywell’s published material describes self-compensating optics and contaminated-optics diagnostics. For an ethylene service application, that combination is useful because the instrument is intended to remain stable in demanding industrial environments rather than rely on combustible-gas contact with a catalytic element.

Key Technical Specifications

Honeywell’s product guide identifies 2108N4001N as the ethylene version with 4-20 mA output, ATEX/IECEx certification, M25 entry, and 316 stainless-steel construction.

HONEYWELL 2108N4001N

Application and Selection Notes

This detector is intended for fixed-point monitoring of flammable ethylene in industrial areas where explosive atmospheres are possible. Typical applications include petrochemical plants, chemical processing units, tank farms, offshore facilities, and other hydrocarbon-handling installations.

The N suffix is important. This configuration uses the standard 4-20 mA output without HART; Honeywell lists 2108N4001H as the corresponding HART-enabled ethylene version. The two should not be treated as electrically identical just because the main model number is similar.

Calibration is another purchasing point. Honeywell-related documentation specifies a dedicated ethylene calibration, with 2108D3240 identified for 100% LEL ethylene calibration. Make sure the installed detector and calibration accessory match the gas being monitored.

Advantages and Limitations

Advantages

• Dedicated ethylene calibration
• 0-100% LEL measuring range
• 4-20 mA analog output
• 316 stainless-steel enclosure
• IP66/IP67 environmental protection
• ATEX/IECEx hazardous-area certification
• Infrared sensing without catalytic poisoning
• Built-in optical diagnostics
• Suitable for remote functional gas testing

Limitations

This is a fixed gas detector, not a portable analyzer. It must be installed with the correct mechanical orientation, wiring, calibration arrangement, and certified hazardous-area installation method.

The N version also does not provide the HART overlay available on the H variant. If remote digital diagnostics are required, the exact suffix should be reconsidered before purchase.

Global Procurement and Shipping Notes

For international orders, list the full 2108N4001N part number and gas calibration on the Commercial Invoice and Packing List. Do not declare it merely as a “sensor.” The calibration and hazardous-area classification are material characteristics for receiving and compliance review.

Country of origin should be taken from the physical product label or supplier documentation. Do not infer origin solely from the seller’s shipping address.

Quality Inspection and Test SOP

1. Inbound inspection

Check the nameplate, serial number, calibration identification, certification markings, M25 entry, stainless-steel housing, optical window, weather protection, and dust barrier. Look for corrosion, impact damage, contamination, or evidence of prior repair.

2. Live test

Use the approved Optima Plus commissioning equipment and calibration procedure. Verify power-up diagnostics, 4-20 mA output, detector status, optical diagnostics, and response to an approved test gas. Record the actual result in a Test Report.

3. Electrical testing

Verify supply polarity, wiring continuity, and grounding according to the installation manual. Do not apply arbitrary high-voltage insulation tests directly to the detector electronics.

4. Calibration verification

Record the detector’s gas calibration and identification. Confirm that the calibration curve corresponds to ethylene service. Check the date and status of any associated calibration equipment before commissioning.

5. Final QC

Protect the optical assembly from impact and contamination, use a rigid carton with suitable cushioning, and attach a QC Passed label with inspection date. Test photographs or video can be provided when the relevant test has actually been completed.

Common Replacement Risks

Calibration mismatch: An ethylene detector should not be treated as interchangeable with every hydrocarbon-calibrated Optima Plus unit. Check the gas calibration before shipment.

N/H suffix mismatch: 2108N4001N is the 4-20 mA version, while 2108N4001H adds HART. Verify the control-system requirement before ordering.

Hazardous-area installation error: ATEX/IECEx certification applies only when the complete installation follows the relevant approval requirements. Check gland, barrier, grounding, and installation method.

Optical contamination: Dirt or condensation on the optical path can affect measurement quality. Honeywell’s design includes contaminated-optics diagnostics and dynamic heating, but maintenance procedures still matter.

Power wiring: The specified supply is 18-32 VDC. Check voltage at the detector terminals, not just at the control cabinet power supply.

One field habit is worth keeping: photograph the detector label and cable termination before removal. It gives procurement and commissioning teams a clean reference.

Related Models

2108N4000N: Searchpoint Optima Plus hydrocarbon-calibrated version with 4-20 mA output and the same general ATEX/IECEx configuration.

2108N4001H: Ethylene-calibrated version with HART over the 4-20 mA signal.

2108N4011N: Related ethylene configuration with remote gassing-cell arrangement.

2108D3240: Calibration gas reference identified for 100% LEL ethylene applications.

Quick Conclusion

• Honeywell Searchpoint Optima Plus infrared gas detector.
• Dedicated for ethylene detection.
• 0-100% LEL measuring range.
• 4-20 mA output without HART.
• 18-32 VDC supply, 24 VDC nominal.
• 316 stainless-steel housing with M25 entry.
• IP66/IP67 and ATEX/IECEx-certified configuration.
• ⚠️ Verify calibration, certification marking, suffix, and actual stock before purchase.

FAQ

What is the HONEYWELL 2108N4001N?

It is a Searchpoint Optima Plus fixed point infrared flammable-gas detector configured for ethylene.

What gas does it detect?

This configuration is specifically calibrated for ethylene with a published 0-100% LEL measuring range.

What output does it provide?

The N configuration provides a 4-20 mA analog output. HART is available on the corresponding H configuration instead.

What power supply is required?

The published supply range is 18-32 VDC, with 24 VDC nominal operation and less than 4.5 W maximum power consumption.

Is it suitable for hazardous areas?

Yes. The listed configuration is certified for hazardous-area use under ATEX/IECEx schemes. The actual marking and installation method must still be checked against the project requirements.

What should be checked before purchase?

Confirm the complete part number, ethylene calibration, N versus H suffix, certification markings, M25 connection, physical condition, calibration status, test record, warranty, and actual warehouse stock.