Johnson Controls S352AA-2 Module

The Johnson Controls S352AA-2 Module is a professional-grade System 350 pressure stage adder engineered to provide precision multi-stage control in commercial refrigeration and HVAC systems. Designed for seamless integration, this pressure stage module plugs directly into a P352AB pressure control or an A350 series master controller via a 5-pin connector, eliminating the need for complex inter-module field wiring. It features high-capacity SPDT enclosed relays rated for 10 amps non-inductive at 120/240 VAC, making it ideal for condenser fan staging and lead-lag pump applications. Technicians can achieve exact calibration using the onboard 2 to 50 psi differential adjustment and 2 to 50 psi offset range. Housed in a durable NEMA 1 thermoplastic enclosure, the S352AA-2 supports both wall and DIN rail mount configurations. With selectable direct or reverse acting modes via internal jumpers, this module offers the field flexibility required for demanding head pressure control and staging logic in high-performance mechanical environments.

• Modular Compatibility: Plugs directly into P352 series master controllers for rapid multi-stage expansion without additional wiring.
• Precise Tuning: Dual potentiometers allow for independent 2-50 psi offset and differential settings to prevent short-cycling.
• Versatile Mounting: Standard 35mm DIN rail or surface mounting capabilities fit any control cabinet layout.
• Visual Diagnostics: Integrated LED status indicator provides immediate confirmation of relay de-energization or activation.
• Flexible Logic: Field-selectable Direct Acting (DA) or Reverse Acting (RA) operation modes manage various pressure staging requirements.

How many S352AA-2 modules can be added to a single P352 control?
When powered by a Y350R power module, you can daisy-chain up to five stage modules. If using an external 40 VA transformer, the system can support up to nine modules for complex staging.

What is the primary difference between the offset and differential adjustments?
The offset determines the point at which the stage activates relative to the master setpoint, while the differential defines the pressure change required to clear the stage and reset the relay.

Can this module handle heavy motor loads?
Yes, the SPDT relay is rated for 1/2 hp at 120/240 VAC, suitable for direct control of small motors or as a pilot duty trigger for larger contactors.

Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.