DLT-8006N Ultra-Low Temperature Circulating Bath with Magnetic Stirring

Overview

The DLT-8006N Ultra-Low Temperature Circulating Bath with Magnetic Stirring is an engineered thermal management system designed for precision temperature control in demanding laboratory and industrial applications. Utilizing a cascade refrigeration architecture—comprising two independent, hermetically sealed compressors operating with R410A (Stage 1) and a custom non-standard zeotropic blend (Stage 2)—the unit achieves stable operation down to −80 °C while maintaining tight thermal uniformity across its 5 L stainless steel bath chamber. Unlike single-stage low-temperature baths, the cascade design enables rapid cooldown, reduced thermal stress on components, and improved long-term reliability under continuous sub-ambient operation. The system supports both internal immersion-based thermal conditioning and external closed-loop circulation via a high-head, low-heat-output pump (8 L/min flow rate), making it suitable for coupling with external reactors, viscometers, spectroscopic cells, or calorimetric modules requiring precisely regulated coolant delivery. Its dual-mode thermal control—simultaneous or independent activation of heating and refrigeration—allows seamless transition between cooling and warming protocols without manual reconfiguration.

Key Features

• Advanced PID temperature controller with XMT architecture, offering real-time display of setpoint and actual bath temperature at 0.01 °C resolution (user-selectable); programmable ramp-soak profiles supported via front-panel interface.
• ABS-molded ergonomic housing with rounded-edge safety design; front-accessible side panels require no tools for removal, facilitating routine maintenance and coil inspection.
• Cascade refrigeration system with Hitachi compressors ensures consistent performance at extreme low temperatures; integrated overheat and overcurrent protection circuits safeguard compressor longevity.
• Hermetically sealed, brushless magnetic drive circulation pump delivers quiet, vibration-free fluid motion with negligible heat generation—critical for sensitive optical or electrochemical measurements.
• 304 stainless steel inner tank, deck, and refrigerant coil surface treatment resist corrosion from aqueous, ethylene glycol, or ethanol-based coolants; optimized coil geometry enhances thermal transfer efficiency.
• Comprehensive safety suite includes dry-run detection for heater elements, over-temperature cut-off with audible/visual alarm, automatic power-loss recovery, and thermal fuse backup.
• Front-mounted quick-connect 304 stainless steel bayonet fittings (inlet/outlet) and concealed drain valve enable rapid fluid exchange and system servicing without disassembly.
• Standard configuration includes insulated silicone circulation tubing, thermal cover plate, and drain spool; optional accessories include integrated magnetic stirrer (speed-adjustable, 0–1200 rpm), universal flask support stand, and PT100 calibration port.

Sample Compatibility & Compliance

The DLT-8006N accommodates standard laboratory glassware (e.g., 100–1000 mL jacketed reactors, U-tube viscometers, quartz cuvettes) within its 18 × 14 cm open bath aperture and 27 × 20 × 13 cm internal chamber. It is compatible with water, 30–60% aqueous ethylene glycol, and low-viscosity silicone oils—provided fluid viscosity remains below 50 cP at operating temperature. The unit complies with IEC 61010-1:2010 for electrical safety in laboratory equipment and meets CE marking requirements for EMC (EN 61326-1) and low-voltage directives. While not certified for GMP manufacturing environments, its temperature stability (±0.05 °C), audit-ready parameter logging (via optional RS485/Modbus interface), and configurable alarm thresholds support GLP-aligned workflows in QC labs conducting ASTM D2857 (viscosity), ISO 291 (conditioning), or USP environmental validation studies.

Software & Data Management

The DLT-8006N operates autonomously via its embedded XMT controller but supports optional digital integration through an RS485 serial interface compliant with Modbus RTU protocol. When connected to a host PC or SCADA system, users can remotely monitor real-time bath temperature, compressor status, pump duty cycle, and alarm history. Logged data—including timestamps, setpoints, deviations, and event flags—is exportable as CSV for traceability. Though the base unit does not include FDA 21 CFR Part 11-compliant electronic signatures or audit trails, third-party middleware solutions (e.g., LabArchives, DeltaV) may be deployed to meet regulated data integrity requirements for pharmaceutical or clinical trial support applications.

Applications

• Low-temperature reaction kinetics studies in synthetic organic chemistry and catalysis research.
• Calibration and verification of thermocouples, RTDs, and infrared pyrometers across extended thermal ranges.
• Stabilization of laser diodes, photomultiplier tubes, and CCD detectors requiring cryogenic thermal anchoring.
• Controlled-cooling protocols for polymer crystallization analysis (DSC sample prep) and protein folding assays.
• External circulation cooling for rotary evaporators, HPLC column ovens, and FTIR spectrometer beam paths.
• QC testing of battery electrolyte conductivity, lithium-ion cell thermal runaway simulation, and aerospace material low-temp tensile conditioning.

FAQ

What coolant fluids are recommended for operation at −80 °C?
Ethanol/water (30/70 v/v) or specialized low-temperature silicone oils (e.g., DC200 series) with pour points below −90 °C are validated for sustained use. Avoid pure water or glycerol-water mixtures below −20 °C due to freezing risk.
Can the magnetic stirrer be retrofitted to an existing DLT-8006N unit?
Yes—the stirrer module is mechanically and electrically decoupled; installation requires only removal of the standard deck plate and mounting of the OEM stirrer assembly with included hardware.
Is the temperature stability specification (±0.05 °C) guaranteed across the full −80 °C to ambient range?
Yes—stability is verified per ISO 17025-accredited procedures at three points: −80 °C, 0 °C, and 25 °C, with load conditions simulating typical 500 mL glass reactor immersion.
Does the unit support external temperature feedback control using a user-supplied probe?
No—the DLT-8006N regulates exclusively via its internal Pt100 sensor; external probe input is not supported in standard firmware.
What is the maximum allowable backpressure for external circulation loops?
The integrated pump is rated for ≤1.2 bar (17 psi) static head pressure; exceeding this may reduce flow rate and compromise temperature uniformity in remote vessels.