A99BC-300C Johnson Controls Sensor

Overview

The Johnson Controls A99BC-300C is a passive Positive Temperature Coefficient (PTC) silicon temperature sensor designed to provide an economical and highly accurate solution for environmental monitoring. Part of the A99B Series, this splashproof sensor features a calibrated PTC thermistor element that combines the accuracy advantages of platinum-based sensors with the high resistance variation of traditional thermistors. This calibration allows for easy sensor exchange without the need for system recalibration. Housed in a durable stainless steel probe, it is engineered for exceptional long-term stability and reliability in demanding commercial HVAC and refrigeration systems, and it is built for compatibility with modular electronic controllers such as the System 450.

Features

• Calibrated Sensing Element: Employs a factory-calibrated PTC silicon thermistor that ensures excellent accuracy and facilitates sensor swapping without recalibration.
• High-Temperature Cable: Equipped with a heavy-duty 9-3/4 foot (3 meter) silicon lead wire insulation capable of withstanding extreme temperatures.
• Durable Construction: Features a rugged stainless steel sensing bulb/probe that resists corrosion and allows for deployment in diverse environments.
• Splashproof Design: Built to withstand moisture and condensation, making it ideal for refrigeration applications.
• Extended Wiring Capability: Lead wire can be extended up to 800 feet (244 meters) with minimal impact on output accuracy when properly accounted for.

Specifications

• Sensor Type: Positive Temperature Coefficient (PTC) Silicon Sensor
• Reference Resistance: 1,035 ohms at 77 F (25 C)
• Sensing Range: -40 to 248 F (-40 to 120 C)
• Accuracy: +/- 0.9 F (+/- 0.5 C) between 5 and 167 F (-15 and 75 C)
• Cable Length: 9-3/4 feet (3 meters)
• Lead Wire Gauge: 22 AWG
• Probe Material: Stainless Steel
• Maximum Allowable Bulb Temperature: 257 F (125 C)
• Ambient Operating Humidity: 0 to 100% RH (condensing)
• Compatibility: Designed for use with System 450 Modular Controls, System 27 NOVA, MR/MS series, and other electronic control modules.

Applications

• Refrigeration Systems: Ideal for monitoring temperatures in walk-in coolers, reach-in coolers, freezers, and commercial display cases.
• Defrost Termination: Commonly used for defrost termination temperature sensing to optimize energy efficiency in cooling equipment.
• HVAC Monitoring: Suitable for return air, space, and outdoor air temperature sensing across commercial and industrial environments.
• Condenser Fan Cycling: Used to sense temperature for managing condenser fan operations in HVAC systems.
• Process Systems: Applicable for general process cooling, heating applications, and liquid immersion environments when paired with a compatible bulb well.