Julabo CORIO CD-5 Open-Circuit Heating Circulator

Overview

The Julabo CORIO CD-5 is a precision-engineered open-circuit heating circulator designed for demanding laboratory applications requiring stable, controllable thermal environments. Operating on the principle of forced convection via an integrated high-efficiency circulation pump, the CD-5 delivers uniform heat transfer to both internal samples and external systems through its dual-mode circulation architecture—supporting both internal bath immersion and external closed-loop temperature control. Its operational range spans from +5 °C to +150 °C, making it suitable for applications involving low-viscosity aqueous media, silicone oils, and other thermally stable heat-transfer fluids. The device employs a robust stainless-steel bath construction with corrosion-resistant heating coils, eliminating scale formation and ensuring long-term thermal fidelity. Unlike basic thermostats, the CD-5 integrates Julabo’s proprietary ACC (Adaptive Cascade Control) algorithm alongside standard PID regulation, enabling dynamic response to load changes while maintaining stability within ±0.03 °C across the full operating range—a specification validated under ISO/IEC 17025-aligned internal calibration protocols.

Key Features

• Precision temperature control via dual-stage PID + ACC algorithm, optimized for rapid equilibration and minimal overshoot during setpoint transitions
• ATC1 (Absolute Temperature Calibration) functionality allows user-performed single-point calibration at any temperature within the working range, traceable to NIST-traceable reference standards
• High-brightness white LED display with adjustable resolution (0.01–0.1 °C), viewable from distances up to 3 meters under typical lab lighting conditions
• Submersible controller design with adjustable immersion depth (7.5–16.5 cm), accommodating variable bath geometries and fluid levels
• Rotatable internal circulation outlet (M16×1 thread) for flexible hose routing and optimal flow distribution in custom fixtures
• Integrated safety architecture including overtemperature cutoff, low-level float switch with audible/visual alarm and automatic power disconnection, and lockable IEC 60320 C14 power inlet
• Thermally isolated electronics compartment with optimized airflow path, ensuring continuous operation at ambient temperatures up to 40 °C without derating
• Compliance with DIN 12876-1 Class III (FL) for flammable liquid handling, EN 61010-1 for electrical safety, and EN 61326-1 for electromagnetic compatibility

Sample Compatibility & Compliance

The CD-5 supports a wide range of sample formats and external instrumentation interfaces. Internally, samples up to Ø15 cm × 15 cm height can be immersed directly in the 4.5 L stainless-steel bath. Externally, it interfaces seamlessly with jacketed reactors, viscometers, polarimeters, HPLC columns, electrophoresis units, and spectrophotometers via standardized 8–12 mm tubing connections. All wetted parts—including the bath, heater coil, and pump head—are constructed from AISI 316 stainless steel, certified per ASTM A240 and compliant with USP for extractables profiling in regulated environments. The system meets GLP documentation requirements when used with optional audit-trail-enabled software (e.g., Julabo WinTemp Pro), supporting 21 CFR Part 11-compliant electronic records where configured with digital signature modules.

Software & Data Management

While the CD-5 operates autonomously via its front-panel interface, it supports RS232 and optional USB/Ethernet connectivity for integration into centralized lab management systems. When paired with Julabo WinTemp Pro v4.x or higher, users gain access to real-time data logging (≥1 Hz sampling), programmable ramp/soak profiles, remote setpoint adjustment, and automated report generation in PDF or CSV format. All logged temperature events—including alarms, calibration actions, and power cycles—are timestamped and stored with hardware-enforced write protection. Audit trails comply with ALCOA+ principles (Attributable, Legible, Contemporaneous, Original, Accurate, Complete, Consistent, Enduring, Available) and are exportable for regulatory review without modification.

Applications

• Thermal conditioning of reference standards prior to metrological verification (e.g., viscosity calibration oils per ASTM D445)
• Stabilization of optical components in refractometers and polarimeters to minimize thermal drift during measurement
• Temperature control of chromatographic columns in GC and HPLC systems to ensure retention time reproducibility
• Material testing per ISO 6721-1 (dynamic mechanical analysis) and ASTM D3418 (DSC sample prep)
• Controlled heating of reaction mixtures in jacketed glass reactors (≤2 L volume) with external recirculation
• Preconditioning of biological samples for enzymatic assays requiring strict thermal consistency (e.g., ELISA plate incubation support)

FAQ

What is the maximum recommended fluid volume for the CD-5 bath?
The CD-5 has a nominal bath capacity of 4.5 L, with a minimum fill level of 3.5 L to ensure proper immersion of the heating element and sensor.
Can the CD-5 be used with silicone oil or other non-aqueous heat-transfer fluids?
Yes—the stainless-steel construction and sealed pump design are compatible with common synthetic heat-transfer fluids, provided their flash point exceeds 150 °C and viscosity remains below 100 cSt at operating temperature.
Is external cooling capability available for the CD-5?
No—the CD-5 is a heating-only circulator; however, optional external cooling coils (order code: COIL-CD) can be installed in the bath for passive heat dissipation in low-duty-cycle applications.
Does the CD-5 support validation documentation packages for GxP environments?
Yes—Julabo provides IQ/OQ documentation templates aligned with ASTM E2500 and EU Annex 15, including as-delivered temperature mapping reports and factory calibration certificates traceable to DAkkS-accredited standards.
How often should ATC1 calibration be performed?
Julabo recommends annual ATC1 verification using a calibrated reference thermometer; frequency may increase based on usage intensity and internal quality procedures, particularly in regulated labs subject to FDA or EMA inspection.