Honeywell 1226-9001

Description

Technical Specifications:

• Part Number: 1226-9001
• Gas Detected: Carbon Monoxide (CO) — 0–500 ppm range (confirm specific gas variant)
• Sensor Type: Electrochemical (CO-specific)
• Output: 4–20 mA (loop-powered, 2-wire)
• Alarm Relays: 2 SPDT relays — 2 A @ 30 VDC / 250 VAC
• Alarm Setpoints: Low Alarm, High Alarm (programmable)
• Accuracy: ±3 ppm or ±5% of reading (whichever is greater)
• Response Time (T90): < 30 seconds
• Operating Temperature: -40°C to +55°C (-40°F to +131°F)
• Operating Humidity: 0–95% RH (non-condensing)
• Enclosure Rating: NEMA 4X / IP66 (weatherproof)
• Power Supply: 18–30 VDC
• Process Connection: 3/4″ NPT conduit entry (bottom)
• Dimensions: 178 mm × 127 mm × 95 mm
• Weight: 1.2 kg (2.6 lb)

Functional Features:

• Dual alarm relays with independent setpoints
• 4–20 mA output for DCS/PLC integration
• Non-intrusive calibration via magnet or HART
• LED indicators: Power, Alarm 1, Alarm 2, Fault
• Fault relay for sensor failure detection

Performance Parameters:

• Sensor Life: 2 years (CO electrochemical)
• Warm-Up Time: < 60 seconds
• Zero Drift: < ±2 ppm per month
• EMC: EN 61326, FCC Part 15 Class A
• Certifications: UL 2075, CSA C22.2, ATEX Zone 2 (if applicable)

Structural Features:

• UV-stabilized polycarbonate housing
• 3/4″ NPT conduit entry with gland
• Terminal block cover with gasket seal
• Wall-mount bracket included

Working Principle:
CO gas diffuses through a membrane into the electrochemical cell, where it is oxidized at the working electrode, generating a current proportional to gas concentration. The electronics convert this current to a 4–20 mA signal. When concentration exceeds programmable setpoints, the alarm relays activate.

Key Advantages:

• NEMA 4X / IP66 rating for outdoor and corrosive environments
• Dual relays enable staged alarm response (warn + evacuate)
• 2-year sensor life reduces maintenance cost
• HART-compatible for remote configuration

Applicable Industries: Oil and gas, chemical plants, refineries, wastewater treatment, mining, confined space monitoring

Installation Requirements:

• Mount 1.5–3.0 m above floor (CO is near-neutral buoyancy)
• Use shielded twisted-pair cable for 4–20 mA signal
• Loop resistance: 100–600 Ω
• Conduit entry must use provided NPT gland

Usage Notes:

• Bump test sensor monthly with calibration gas
• Full calibration every 6 months or per regulatory requirement
• Replace sensor when “Fault” LED illuminates
• Do not paint or coat the sensor window