The Fluke 2635A Hydra Data Bucket is a portable 21-channel data acquisition unit designed for gathering and transporting large volumes of measurement data, including extended operation from remote locations. The Hydra Data Bucket is part of the broader Hydra Series, which also includes the 2625A Data Logger and the 2620A Data Acquisition Unit. The 2635A is distinguished within the family by its removable PCMCIA memory card storage, which the 2625A (internal storage) and 2620A (no nonvolatile storage) do not provide.

A data acquisition instrument captures readings from multiple sensor inputs over time, recording values for later analysis or transmitting them in real time to a host computer. The Hydra Data Bucket is used for standalone monitoring operations where data is collected on the memory card and later retrieved at a PC, and for PC-based data acquisition where the RS-232 link feeds readings directly into application software. The datasheet describes its role in test and monitoring systems, remote-location data gathering, and applications that mix standalone recording with periodic upload via the Hydra RS-232 port, an optional external PC memory card drive, or a standard PCMCIA slot on the user's computer.

Brand Heritage

Fluke Corporation is the original manufacturer of the Hydra Series. The Hydra family was developed during the era when Fluke operated as a standalone public company before its 1998 acquisition by Danaher Corporation. Fluke has continued to operate under its own brand name through the Danaher era and into the current Fortive Corporation, which was spun off from Danaher in 2016 and now serves as Fluke's parent company.

Compare Other Models in This Series

The Hydra Series comprises four data acquisition instruments built on a common 21-channel Universal Input Module front end with shared measurement specifications. All four models share the same analog measurement performance, the same isolation and safety ratings, and the same Universal Input Module that accepts thermocouples, RTDs, DC and AC voltage, resistance, and frequency without external signal conditioning.

The models differ along two axes: nonvolatile data storage and host interface. The 2635A Hydra Data Bucket adds PCMCIA memory card storage to the RS-232 interface, supporting standalone logging with later upload. The 2625A Hydra Data Logger provides internal nonvolatile memory storing more than 2,000 scans with RS-232 transfer. The 2620A Hydra Data Acquisition Unit has no internal nonvolatile storage and is designed for direct PC connection via RS-232, while the 2620A/05 substitutes an IEEE-488 interface for the RS-232 (the two interfaces are mutually exclusive when IEEE-488 is in use).

Each pre-owned Hydra Series model below is its own dedicated product page with condition-matched pricing, inventory status, and quote workflow. Use the comparison table to confirm which storage and interface combination matches the deployment, then navigate to the specific model page for current availability.

Within the Hydra Series, the 2635A Data Bucket is the configuration optimized for standalone field logging with bulk data offload. Its PCMCIA memory card storage, multiple card capacity options (256 KB through 4 MB), and ability to transfer real-time data to a PC while simultaneously recording to the card distinguish it from the internally-stored 2625A and the PC-tethered 2620A. The datasheet explicitly identifies the 2635A as the right choice for gathering and transporting large volumes of data and for working extended periods from remote locations.

The compare-models table below summarizes the four Hydra Series variants by storage type and host interface. All four share identical analog measurement performance — the Universal Input Module, the 17-bit ADC, the channel count, the isolation ratings, and the temperature, humidity, and EMI specifications are common across the family.

Selection across the family is driven by deployment mode rather than measurement performance. Standalone field logging with later card retrieval favors the 2635A. Standalone logging with serial upload at a fixed location favors the 2625A. Direct PC-tethered acquisition in a test rack favors the 2620A.

Additional differences in specifications beyond the few shown above are not listed here — see each model's full specifications below.

Accessories Supplied

• Instrument
• Universal Input Module
• Line cord
• User manual
• Starter Software (DOS)
• RS43 cable

Product Core & Specifications

About this used unit

• Warranty included on every pre-owned Hydra Series unit shipped from ValueTronics
• Functional verification performed in-house against the published measurement specifications before shipment
• Standard Calibration Upgrade Options: No Calibration Required, NIST Traceable, Z540.1 or ISO 17025 with Data, Z540.3 Guardbanding with Data.
• Note that unnecessary accessories may not be included (contact Test Architect to confirm).

Please review the Manufacturer's Data Sheet to verify published specifications. Feedback on this webpage is always welcome — please reach out to your Test Architect at any time for questions or concerns. Thank you, we truly appreciate you being our customer.