Julabo CD-19M General-Purpose Circulating Water Bath

Overview

The Julabo CD-19M is a high-precision, general-purpose circulating water bath engineered for stable thermal conditioning of samples, reactors, and external equipment in research laboratories, quality control environments, and industrial R&D settings. Unlike basic immersion heaters or non-circulating baths, the CD-19M employs a closed-loop internal circulation system with a robust stainless-steel heating coil and a high-capacity pump (15 L/min, 0.35 bar), enabling uniform temperature distribution across its 19-liter working volume — critical for applications requiring reproducible thermal profiles over extended durations. Its operational range spans from ambient +5 °C up to 150 °C, making it suitable not only for aqueous media but also for silicone oils and other heat-transfer fluids compatible with stainless-steel wetted parts. The unit operates exclusively in heating mode and does not incorporate refrigeration; this design prioritizes thermal stability, energy efficiency, and long-term reliability within elevated temperature regimes.

Key Features

• PID1 + ACC (Intelligent Cascade Control) dual-stage temperature regulation ensures rapid setpoint attainment and minimal overshoot, even under dynamic load conditions.
• ATC1 (Absolute Temperature Calibration) allows user-performed single-point calibration at any temperature within the operating range, maintaining traceable accuracy without third-party intervention.
• Adjustable controller immersion depth (7.5–16.5 cm) accommodates varying bath configurations and sensor placement requirements for optimal thermal feedback.
• Rotatable internal circulation outlet enables flexible flow direction alignment — essential when integrating with external jackets, coiled tubing, or custom reaction vessels.
• Low-noise pump and acoustically damped housing (<45 dB(A) at 1 m) meet stringent laboratory noise specifications, supporting quiet-zone environments such as analytical suites and cell culture facilities.
• Comprehensive safety architecture includes continuous overtemperature protection across the full RT+5–150 °C range, automatic dry-run shutdown via float-level sensor with audible/visual alarm, and lockable IEC 60320 C14 power inlet compliant with EN 61010-1.
• High-brightness white LED display provides clear remote readability, while intuitive rotary encoder interface supports tactile operation with glove compatibility.

Sample Compatibility & Compliance

The CD-19M is designed for use with standard laboratory glassware (e.g., flasks, beakers, jacketed reactors) and externally connected systems requiring precise thermal input. Its stainless-steel bath chamber and corrosion-resistant heating coil ensure compatibility with deionized water, glycol-water mixtures, and low-viscosity silicone oils (up to 150 °C). The unit conforms to DIN 12876-1 Class III (FL) for both internal and external temperature control applications — certifying suitability for use with open and closed external circuits. Regulatory compliance includes EN 61010-1 (safety of electrical equipment for measurement, control, and laboratory use), EN 61326-1 (EMC requirements for laboratory instruments), and RoHS/WEEE directives. It meets foundational requirements for GLP-compliant thermal validation protocols when paired with calibrated reference thermometers and documented calibration records.

Software & Data Management

While the CD-19M operates as a standalone instrument with no built-in data logging or PC connectivity, its analog-compatible 0–10 V output signal (optional accessory) permits integration into centralized monitoring systems or SCADA platforms for real-time temperature tracking. All calibration and operational parameters are retained in non-volatile memory during power cycles. For audit-ready environments, users may implement external validation workflows aligned with ISO/IEC 17025 or FDA 21 CFR Part 11 guidelines using third-party data acquisition hardware and timestamped digital logs — provided appropriate electronic signature and change-control procedures are established per organizational SOPs.

Applications

• Enzyme kinetics and protein denaturation studies requiring tightly controlled thermal ramps and plateaus.
• Calibration of temperature-sensitive sensors (e.g., RTDs, thermistors) against NIST-traceable references.
• Thermal preconditioning of polymers, adhesives, and composites prior to mechanical testing.
• Stabilization of chromatography columns, viscometers, and spectrophotometer sample compartments.
• Heating and circulation support for jacketed bioreactors, distillation assemblies, and reflux condensers.
• Accelerated aging tests per ASTM D573, ISO 188, or IEC 60068-2-11 standards.

FAQ

Is the CD-19M suitable for oil-based heat transfer media?

Yes — its stainless-steel construction and 150 °C upper limit support common silicone and mineral oils, provided viscosity remains below 100 cSt at operating temperature.
Does it support external temperature probes for independent verification?

The unit accepts optional PT100 probe inputs via analog interface (accessory required); however, primary control relies on its integrated high-stability sensor.
Can it be used in GMP-regulated environments?

It satisfies core hardware safety and EMC requirements; full GMP compliance depends on site-specific IQ/OQ/PQ execution, calibration frequency, and documentation practices.
What maintenance is recommended for long-term stability?

Annual verification of ATC1 calibration, periodic inspection of the float-level switch mechanism, and descaling of the bath chamber (if using hard water) are advised.
Is the bath opening compatible with standard lab stands and clamps?

The 36 × 30 cm aperture and reinforced rim allow secure mounting of universal support frames, clamp holders, and overhead stirrer assemblies.