Foxboro 43AP-PA42N/TA-3B Pneumatic Indicating Controller

Product Description: The 43AP-PA42N/TA-3B is a classic Foxboro 43AP series panel-mount pneumatic indicating controller, Style B construction. It receives pneumatic measurement signal, compares process variable against setpoint and outputs a 3–15 psi pneumatic signal to drive pneumatic control valves. This unit features local analog indication for process value, setpoint and output, with PID (Proportional + Integral + Derivative) control algorithm. The suffix TA-3B defines internal configuration, transfer station and calibration range package for panel installation in legacy pneumatic control panels.

Features:

• Panel mount version (P) of Foxboro 43AP pneumatic controller, Style B housing
• 3–15 psi standard pneumatic output signal, supply air 20 psi (140 kPa)
• Full PID control: proportional band 4–400%, integral 0.01–50 min, derivative 0.05–50 min
• Built-in local pointer indication for PV, set point and output signal
• Bumpless auto/manual transfer function for smooth switching without valve shock
• IP53 / NEMA Type 3 weatherproof enclosure, resistant to plant dust and moisture
• 1/4 NPT air tubing connections, compatible with traditional pneumatic loop systems

Applications:

• Legacy petrochemical pneumatic control panels for pressure, flow, temperature and level control
• Refinery, oil & gas process loops with pneumatic control valves
• Power plant auxiliary system old pneumatic control cabinet retrofit spare
• Pulp & paper, chemical batch process backup pneumatic regulation
• Offshore platform legacy pneumatic instrument replacement

FAQ:

Q: What does PA42N / TA-3B mean?
A: P=Panel mount, A4=PI control, 2=3-15psi output, N=no standard transfer; TA-3B is the special option and range code for this variant.

Q: Can it be replaced with other 43AP models?
A: Only same control action, signal range and transfer option can be interchanged; suffix code TA-3B must be matched.

Q: Is this controller still in production?
A: The 43AP series is fully discontinued. Available stock is surplus NOS or fully rebuilt & calibrated refurbished units.