The Series UDL Universal Input Data Loggers are available with 0, 2 or 4 universal inputs. Each universal input can be individually configured to accept a thermocouple, RTD, thermistor, voltage, or current input. All Series UDL data loggers have an internal temperature sensor and a digital input, which can be used as a trigger to start logging or as a pulse counter for interfacing with flow meters or other sensors with a pulse output. Optional feature include an internal humidity sensor and an LCD display and an external humidity and temperature sensor. The Series UDL loggers interface to the USB port of a PC. The unit includes software, USB connection cable and installed battery.• Inputs: RTD, thermocouple, thermistor, current, voltage, slidewire. • Range: Internal temperature: -22 to 158°F (-30 to 70°C); Internal RH: 0 to 100%; External temperature: -22 to 158°F (-30 to 70°C); External RH: 0 to 100%. • Accuracy: Internal temperature: ±1°F (± 0.5°C); External temperature: ±1°F (±0.5°C) over 30 to 122°F (0 to 50°C), ±2°F (±1°C) over -30 to 32°F (-30 to 0°C) and 122 to 158°F (50 to 70°C); Internal/external RH: ±2.0% RH over 10%-90%, ±4.0% RH over 0-10% and 90-100% RH. • Memory Size: 0 or 2 universal inputs: 62,000 readings; 4 universal inputs: 128,000 readings. • Resolution: All universal inputs: 16 Bit; Internal & external temperature: 12 Bit; Internal & external RH: 8 Bit. • Sampling Method: Stop when full or continuous logging (wrap when full). • Sampling Rate: Selectable from 1 second to 24 hours. • Computer Requirements: Windows® 98, Windows® 2000, Windows® ME, Windows NT®, Windows® XP, and Windows Vista® operating system with 16 MB RAM, one free USB port. • Power Requirements: 3.6 VDC lithium AA. • Battery Life: 6 years (approx.). • Alarms: Programmable high/low. • Interface: USB port (cable included). • Housing Material: ABS plastic. • Weight: 5.8 oz (165 g). • Agency Approvals: CE, RoHS.