Johnson Controls R310AD-1 Sensing Switch

The Johnson Controls R310AD-1 Sensing Switch is a critical component for contractors looking to eliminate nuisance lockouts in commercial HVACR systems. Built with a solid-state normally open switch, this device detects alternating current (AC) flow in a single circuit without direct electrical connection, providing a 0.5 ampere fixed trip point. It is specifically engineered to interface with low-voltage control circuits, making it the standard current sensing relay for P445 Electronic Lube Oil Controls. By monitoring the current flow to the compressor motor, the R310AD-1 ensures that the electronic timer is de-energized whenever the motor shuts down, effectively preventing lockout cycles during motor overload events.

Designed for professional-grade durability, this switch features a high dielectric material housing that allows for safe mounting inside motor starters or contactor enclosures. The large 0.70-inch (18 mm) sensor hole accommodates heavy-gauge conductors or multiple coils for low-amperage monitoring. With a switching capacity of 0-30 Vac/Vdc at 0.1A, it provides reliable monitoring of HVAC motors, fans, and pumps up to 200 amperes maximum sensing capacity.

Key Benefits

• Solid-State Design: No moving parts ensure long-term reliability in high-cycle HVAC pilot circuit applications.
• Nuisance Lockout Prevention: Accurately senses current drop to de-energize oil failure cutout controls like the P28, P45, and P445.
• Versatile Installation: Compact NEMA 1 enclosure fits into tight electrical cabinets and starters.
• Wide Sensing Range: Monitors equipment from 0.5A up to 200A for broad system compatibility.
• Non-Polarity Sensitive: Simplifies field wiring for technicians during current status switch replacements.

Common Questions

• Can this switch detect a broken belt or coupling? No, this model is designed to sense current flow to the motor; it does not detect mechanical failures like broken belts where the motor continues to run.
• What is the difference between the R310AD-1 and the R310AE-2? The R310AD-1 is designed for low-voltage (0-30V) circuits like the P445, while the R310AE-2 is intended for high-voltage applications.
• Is the trip point adjustable? No, the R310AD-1 has a fixed 0.5A trip point for consistent, "no-fuss" performance in the field.

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.