Foxboro 43AP-PA42N/TA-3B 43AP series pneumatic indicator regulator

Product Description

43AP-PA42N/TA-3B is a Foxboro 43AP series pneumatic indicating controller. TA-3B denotes the liquid-filled thermal bulb temperature measuring element. It is a legacy field-mounted pneumatic controller with PI (Proportional + Integral) control, dual-pointer indication for process variable and setpoint, and bumpless auto-manual transfer. Standard 3~15 psi pneumatic output drives pneumatic control valves directly. This model is discontinued and supplied only as spare part for legacy pneumatic control loops in chemical and power plants, ideal for hazardous, high-temperature and high EMI environments.

Technical Specifications

• Model: 43AP-PA42N/TA-3B
• Series: 43AP Pneumatic Indicating Controller
• Sensing Element: TA-3B liquid-filled thermal bulb for temperature
• Control Action: PI; proportional band 4%~400%, integral time 0.01~50 min
• Output Signal: 3~15 psi (20~100 kPa), with 0~30 psi output gauge
• Supply Air: Nominal 20 psi (140 kPa), operating range 17~23 psi (115~155 kPa)
• Indication Accuracy: ≤±0.5%FS
• Repeatability: ≤±0.2%FS, dead band ≤0.1%FS
• Enclosure: NEMA Type3, IP53, corrosion-resistant fiberglass housing, weatherproof
• Auto-Manual: N version, bumpless transfer with balance gauge
• Air Consumption: approx. 0.5 m³/h
• Dial: Large sector dial, dual red pointers for PV and SP
• Ambient Temperature: -30℃ ~ +80℃
• Mounting: Field pipe / yoke mounting
• Standard: ISA pneumatic instrument standard, suitable for intrinsically safe pneumatic circuits
• Weight: approx. 4.8 kg

Application

1. Local pneumatic closed-loop temperature control for heat exchangers and process lines in refineries and chemical plants
2. Temperature regulation for boiler auxiliary circuits in legacy thermal power plants, driving pneumatic diaphragm control valves
3. Continuous temperature control in classified hazardous areas without electric power supply
4. Spare replacement and retrofitting for existing Foxboro pneumatic instrument systems
5. Standalone temperature PID control for metallurgy and paper mills, independent of DCS

Series Models

43AP-PA42N/TA-1A, 43AP-FA42C/PB-BA, 43AP-FA42C/TA-1A, 43AP-BA42N