The Keysight U2802A is a 31-channel thermocouple input module that delivers precision temperature measurement and signal conditioning for data acquisition systems. It converts low-voltage thermocouple signals into ±10 V outputs compatible with Keysight U2355A and U2356A DAQ devices via SCSI-II 68-conductor connection. The module supports eight standard thermocouple types (J, K, R, S, T, N, E, B) and includes built-in cold junction compensation, open thermocouple detection, and onboard EEPROM calibration storage with NIST traceability.
Technical Specifications
Input Channels & Modes
• 31 differential thermocouple inputs plus 1 cold junction compensation input
• Thermocouple Input Mode: ±100 mV signal acceptance; 10 kSa/s aggregate sampling across all channels; 4 Hz low-pass filter per channel; CMRR > 80 dB
• Voltage Input Mode: Direct ±10 V routing; > 500 kHz bandwidth; 500 kSa/s module sampling rate; CMRR > 60 dB
• Zero Mode: Shorts instrumentation amplifier inputs to measure and subtract offset errors
Signal Conditioning
• Instrumentation amplifier on each thermocouple channel
• Built-in thermistor for cold junction compensation
• Isothermal terminal block construction
• Open thermocouple detection circuitry
• Zeroing function to compensate for temperature and long-term drift
Calibration
• Onboard EEPROM stores per-channel gain and offset factors
• Module ID, serial number, and calibration date stored
• NIST traceable calibration
• Factory restoration available via KMM software
Electrical
• Power: ±12 VDC, 750 mA maximum
• Input overvoltage protection: ±10 V module ground limit; TC+/TC– pins withstand ±17 V differential (short duration)
– Key Features
• Eight thermocouple types per NIST ITS-90 database
• Per-channel amplification and filtering reduces noise
• Retrievable calibration data prior to measurements
• Isothermal design improves measurement accuracy
– Compatibility & Integration
Connects to Keysight U2355A or U2356A DAQ devices via SCSI-II 68-conductor cables.
