The Dickson TP425 is a dual-channel data logger for temperature and humidity monitoring in controlled environments. It combines an internal digital temperature sensor with a monolithic RH IC humidity sensor, delivering ±0.8°F (±0.5°C) accuracy across the primary operating range and ±1.8°F (±1.0°C) at temperature extremes. The unit stores up to 32,512 sample points with configurable logging intervals from 1 second to 24 hours. A 2.5-digit LCD display shows real-time readings or min/max values, while push-button controls enable three start modes: no delay, button-triggered, or delayed start. Data downloads via USB to a compatible PC running DicksonWare™ software in approximately 1 minute when memory is full. The CR123 lithium battery provides one year of typical operation and is user-replaceable in the field. Housed in a compact polycarbonate enclosure measuring 1.34″ × 3.08″ × 2.25″, the TP425 weighs 4 oz and operates across -4°F to +158°F (-20°C to +70°C) at 0% to 95% RH non-condensing conditions. Audio/visual alarms and indicator states (solid, scrolling, flashing, blank) provide at-a-glance logging status.
## Technical Specifications
• **Temperature Range:** -4°F to +158°F (-20°C to +70°C)
• **Temperature Accuracy:** ±0.8°F (±0.5°C) from +20°F to +120°F (-6°C to +48°C); ±1.8°F (±1.0°C) outside this range
• **Humidity Range:** 0% to 95% RH non-condensing
• **Humidity Accuracy:** ±2% RH at 0–60% RH; ±3% RH at 60–95% RH
• **Resolution:** 0.1°F (0.1°C), 1% RH
• **Sample Interval:** 1 second to 24 hours, configurable in 1-second increments
• **Data Storage:** 32,512 total sample points (16,256 per channel)
• **Response Time:** 10 minutes to 63% full scale (internal channel)
• **Display:** 2.5-digit LCD, 1.2″ × 0.9″, TN reflective, 20-second update rate
• **Power Supply:** CR123 lithium battery, user-replaceable; 1 year typical life
• **Enclosure:** Polycarbonate; IP20 rated
• **Dimensions:** 1.34″ × 3.08″ × 2.25″ (3.4 cm × 7.8 cm × 5.7 cm)
• **Weight:** 0.45 kg (1 lb)
## Key Features
• Dual-channel independent logging with min/max tracking
• USB data transfer; 6-foot USB cable included
• Field-user calibration via SW400 software
• Three selectable start modes for experimental flexibility
• Real-time LCD display with status indicators and audio/visual alarms
• Compact form factor for placement in tight or space-constrained environments
## Compatibility & Integration
The TP425 interfaces with DicksonWare™ software (minimum version 13.6) on Microsoft Windows® 98 and later systems. Required PC specifications: 486 MHz or faster processor, 16 MB RAM, one free USB root hub, CD drive, and VGA monitor or equivalent.
