A421ABT-02C Johnson Controls Temperature Control

Overview

The Johnson Controls A421ABT-02C is a line-voltage electronic single-stage temperature control with an integrated duty-cycle timer. Designed for free-cooling and ventilation applications, it features a bright backlit LCD screen with adjustable brightness and a simple three-button touchpad interface. It comes housed in a NEMA 1/IP20 high-impact thermoplastic enclosure suitable for surface or DIN rail mounting.

Features

• Integrated duty-cycle timer for timed ventilation and overcooling protection
• Easy-to-read backlit LCD display with customizable brightness levels
• Three-button touchpad interface for basic and advanced programming
• Adjustable On and Off temperature setpoints for heating or cooling applications
• High and low temperature setpoint stops to restrict unauthorized user adjustments
• Temperature offset capability to align displayed temperature with actual sensed temperature
• Adjustable anti-short cycle delay to protect compressors from short cycling
• Switch-activated temperature setback option via binary input control circuit

Specifications

• Supply Voltage: 120/240 VAC, 50/60 Hz
• Power Consumption: 1.8 VA maximum
• Temperature Control Range: -40°F to 212°F (-40°C to 100°C)
• Output Relay: Single-Pole, Double-Throw (SPDT)
• Control Accuracy: Less than +/- 1.8°F (+/- 1.0°C)
• Enclosure Rating: NEMA 1, IP20 high-impact thermoplastic
• Sensor Type: A99 PTC temperature sensor (1,035 ohm at 77°F), includes A99BB-200C sensor with 6.6 ft cable and 2-inch probe
• Approvals: cULus Listed, FCC Compliant, CE Mark

Applications

• Agricultural ventilation and free-cooling systems
• Duty-cycle ventilation monitoring
• Commercial refrigeration equipment control
• HVAC temperature regulation systems