The Dickson THDX Temperature Humidity Recorder is a dual-channel environmental data logger that simultaneously records temperature, humidity, and dew point on an 8-inch circular chart with real-time digital LCD readout. Designed for precision monitoring in HVAC systems, laboratories, manufacturing facilities, and environmental control applications, the THDX delivers ±1.8°F (±1.0°C) temperature accuracy and humidity accuracy to ±2% RH across the 0–60% range, expanding to ±3% RH between 61–95% RH. The unit accepts user-configurable measurement ranges: −20 to +120°F (−20 to +50°C) or +40 to +110°F (+5 to +40°C) for temperature, with 0–95% RH (non-condensing) for humidity. Dew point calculations span −22 to +122°F (−30 to +50°C).
Technical Specifications
• Temperature: ±1.8°F (±1.0°C) accuracy; thermistor sensor; selectable −20 to +120°F or +40 to +110°F ranges
• Humidity: ±2% RH (0–60%), ±3% RH (61–95%); monolithic IC with thin-film capacitor sensor; 0–95% RH operating range
• Dew Point: −22 to +122°F (−30 to +50°C); ±2°C (±3.6°F) accuracy 30–95% RH; ±49°C (±88.2°F) accuracy 0–5% RH
• Display: Large digital LCD; 1°F (1°C) and 1% RH resolution; simultaneous temperature/humidity or dew point display
• Chart: 8-inch (20.3 cm) diameter circular; 24-hour, 7-day, or 31-day user-selectable intervals
• Sampling: Configurable 10 seconds to 24 hours; 15-minute intervals recommended for warehouse mapping
• Response Time: Temperature 30 seconds (63% step change, 1 CFM); humidity 20 seconds (63% step change, 1 CFM); 2.5 minutes full-scale general response
– Key Features
• 120V AC adapter with 4 “D” cell battery backup (≈72 hours runtime)
• Audio/visual alarms with user-defined high/low setpoints
• 24V DC 0.5A SPST relay contact (NO/NC configurable); normally open, closes on alarm
• Switchable C/F and RH/dew point display modes
– Typical Applications
HVAC system validation, pharmaceutical and food manufacturing environmental compliance, cleanroom monitoring, research laboratories, and warehouse climate mapping.
– Compatibility & Integration
Relay output rated 24VDC, 0.5A. Battery backup does not support alarm or relay functions.
