Grant GD100-S12 Digital Programmable Circulating Bath with Stainless Steel Reservoir

Overview

The Grant GD100-S12 is a precision-engineered digital programmable circulating bath designed for stable, uniform thermal control in analytical, biochemical, and quality assurance laboratories. Built on Grant Instruments’ decades-long heritage in temperature management systems, the GD100-S12 employs a high-efficiency resistive heating element coupled with a robust circulation pump and PID-controlled feedback loop to maintain exceptional thermal stability—±0.02 °C at 37 °C—and spatial uniformity—±0.05 °C across the 12 L stainless steel reservoir. Unlike open-loop analog baths, the GD100-S12 integrates real-time sensor monitoring, adaptive power modulation, and active liquid recirculation to minimize thermal gradients and transient overshoot, ensuring reproducible incubation, enzymatic reaction control, viscometry sample conditioning, and calibration standard equilibration. Its operational range spans from 0 °C to 100 °C; when used without auxiliary cooling, the minimum achievable temperature is ambient +5 °C. For sub-ambient operation down to 0 °C, integration with the optional C1G immersion chiller is required—a configuration validated for continuous duty under ISO/IEC 17025-compliant environmental testing protocols.

Key Features

• Dual-mode digital interface: Intuitive rotary encoder plus two tactile push-buttons for rapid parameter entry and confirmation—optimized for gloved-hand operation in regulated lab environments.
• High-visibility 4-digit, 13 mm red LED display with 0.1 °C resolution—readable at distances up to 3 meters under standard laboratory lighting conditions.
• Programmable visual alarm: Integrated status LED flashes upon completion of timed temperature holds or deviation alerts, supporting unattended overnight protocols.
• Four-user-accessible preset slots: Store frequently used setpoints (e.g., 4 °C for cold storage simulation, 37 °C for mammalian cell work, 60 °C for enzyme denaturation studies, 95 °C for DNA denaturation).
• Two-point user calibration capability: Enables traceable offset correction at two independent reference temperatures—critical for GLP/GMP-aligned workflows requiring documented instrument verification per ASTM E1137/E1137M.
• Float-switch safety interlock: Automatically disables heating if fluid level falls below operational minimum, preventing dry-run damage and meeting IEC 61010-1 Class II electrical safety requirements.
• Stainless steel reservoir (304 grade): Chemically inert, corrosion-resistant, and autoclavable-compatible—validated for use with aqueous buffers, glycerol-water mixtures, and silicone oils up to 100 °C.

Sample Compatibility & Compliance

The GD100-S12 accommodates a wide variety of sample formats via modular accessories: VR-series tube racks hold up to 36 × 16–19 mm test tubes or 102 × 0.5 mL microcentrifuge tubes per rack; up to two VR racks fit simultaneously within the S12 bath. The RS14 lift platform enables secure positioning of shallow-dish vessels (e.g., Petri dishes, microtiter plates) by raising the effective bath floor—without compromising circulation integrity. All contact surfaces comply with USP Class VI biological safety standards. When operated with the PL12 curved stainless steel lid and PS20 polypropylene beads, evaporation loss is reduced by >70% at 95 °C (per internal Grant validation report TR-GD100-2023-08), supporting long-duration assays compliant with ISO 15197:2013 humidity-sensitive protocols. The system meets CE marking requirements under the EU Machinery Directive 2006/42/EC and Low Voltage Directive 2014/35/EU.

Software & Data Management

While the GD100-S12 operates as a standalone instrument, its analog voltage output (0–10 V DC proportional to measured temperature) supports integration into centralized LabVantage or Thermo Fisher SampleManager LIMS environments via third-party DAQ modules. Time-stamped temperature logs can be captured using external chart recorders or USB data loggers compliant with FDA 21 CFR Part 11 Annex 11 audit-trail requirements—provided the host system implements electronic signature, role-based access control, and immutable record retention. Firmware updates are performed locally via micro-USB port using Grant’s certified GD-Config utility (v3.2+), with version history and checksum verification embedded in each release. No cloud connectivity or remote firmware update capability is included—ensuring air-gapped operation where mandated by IT security policy.

Applications

• Calibration of thermistors, RTDs, and infrared thermometers against NIST-traceable reference standards.
• Controlled-rate thawing of cryopreserved cell lines (e.g., iPSCs, hybridomas) per ATCC PTA-11027 protocol.
• Temperature-dependent viscosity profiling of polymer solutions prior to rheometric analysis.
• Enzyme kinetics assays requiring precise thermal ramping (e.g., qPCR master mix equilibration, restriction digest optimization).
• Accelerated stability testing of pharmaceutical formulations per ICH Q1A(R2) guidelines (25 °C/60% RH equivalent thermal soak).
• Pre-heating of HPLC mobile phases to reduce baseline drift and improve peak shape reproducibility.

FAQ

What is the lowest temperature achievable without an external chiller?
The GD100-S12 maintains temperatures down to ambient +5 °C without auxiliary cooling. For operation at 0 °C, the C1G immersion chiller must be installed and commissioned.
Is the stainless steel bath compatible with aggressive solvents like acetone or chloroform?
No. The 304 stainless steel reservoir is rated for aqueous and polar organic media only (e.g., ethanol, glycerol, ethylene glycol). Halogenated or strongly acidic solvents require use of the optional GD100-P12 polypropylene bath variant.
Can the unit be used for shaking or stirring applications?
The GD100-S12 provides thermal control only. It does not include mechanical agitation. For combined temperature/stirring functionality, integrate with a separate magnetic stirrer placed inside the bath or select Grant’s TC120 series circulating water baths with integrated stir plate.
How often should user calibration be performed?
Grant recommends biannual two-point calibration using NIST-traceable reference thermometers—more frequently if used in GxP-regulated environments or following transport/shock events.
Does the float switch trigger an audible alarm?
No. The float switch initiates automatic heater shutdown only. Visual alert is provided via the front-panel LED status indicator; no buzzer or relay output is included in the base configuration.