• 0.0024% DC accuracy
  • 0.5°C thermocouple accuracy
  • Up to 66 universal differential isolated inputs
  • 20 on-board math channels
  • 45 channels/second basic dc scan rate
  • 6.5-digit bench DMM function for front panel inputs
  • One button screen capture
  • Multi-channel real-time data
  • Internal 75,000 scan/setup file memory
  • Category II 300 V safety rating

What's in the Box

  • Relay boards
  • Universal Input Connectors installed
  • Test leads
  • Safety information and 2680A-APSW/L
  • Power cord
  • Screwdriver
  • Traceable calibration report with data


The Fluke Hydra Series III Data Acquisition System / Digital Multimeter continues the legacy of precision, multi-channel data acquisition. The new Series III improves on Hydra's industry-leading thermocouple accuracy and adds a new dimension to how you collect and view data in a portable system.

The 2638A is expandable from 22 to 66 channels of differential analog inputs. A flexible, 22-channel Universal Input Connector lets you connect and disconnect any type of input to any channel, quickly and easily. Selectable inputs include dc voltage, ac voltage, resistance, thermocouple, RTD, thermistor, frequency and dc and ac current. You can also use the 2638A with optional software and other Fluke data loggers to create a flexible, customized data acquisition system with an almost unlimited number of input channels.

The 2638A features a DC measurement accuracy of 0.0024 % and a basic 0.5°C thermocouple accuracy. A full-color display, easy-to-use menu system and industrial safety ratings put the 2638A in a category of its own as a precision data acquisition system. The dedicated 6.5 digit digital multimeter (DMM) mode provides additional utility and value.