Shanghai Yiheng CU/DK Series Precision Water Bath Circulators – Stainless Steel Constant Temperature Baths with Internal/External Circulation

Overview

The Shanghai Yiheng CU/DK Series Precision Water Bath Circulators are laboratory-grade constant temperature systems engineered for high-reproducibility thermal conditioning of samples, reagents, and instruments. These units operate on the principle of convective heat transfer via precisely regulated water circulation—either internally within the bath chamber or externally through a closed-loop system connected to peripheral equipment (e.g., spectrophotometer jackets, viscometer thermostats, or reaction blocks). Designed for continuous operation under ambient conditions (20°C, 50% RH), they deliver stable thermal environments across a wide working range from ambient +5°C up to 99°C. All models feature dual-wall stainless steel construction (inner tank and outer casing), ensuring corrosion resistance, mechanical durability, and long-term dimensional stability—critical for GLP-compliant laboratories where equipment integrity directly impacts data traceability.

Key Features

• High-purity 304 stainless steel inner tank and outer housing—resistant to oxidation, chemical splash, and repeated cleaning cycles
• Digital microprocessor-based temperature controller with 0.1°C resolution and adjustable ramp rate (optional multi-segment programming)
• Integrated timer function supporting automatic start/stop scheduling—enabling unattended overnight or weekend operation
• Over-temperature protection with simultaneous audible buzzer and visual LED alert—prevents sample degradation and thermal runaway
• Electromagnetic circulation pump (standard on DK-8AXX, DK-8AD, DKB-600B, and DK-8D models) offering variable-speed output for precise flow control (0–3 L/min typical range)
• Triple independent bath configuration (TS-030 model) with individual PID controllers per chamber—eliminates cross-contamination risk and enables parallel experiments at different setpoints
• Front-panel calibration access for field verification of sensor accuracy against NIST-traceable reference thermometers

Sample Compatibility & Compliance

These baths accommodate standard laboratory glassware (e.g., beakers, flasks, cuvettes, and immersion probes) as well as OEM accessories requiring external cooling/heating interfaces. The open-bath geometry supports immersion depths up to 150 mm (CU-420) or 190 mm (DK-600A), while the transparent acrylic front panel on the DKB-600B model permits real-time visual monitoring without lid removal. Units comply with GB/T 5170.2–2017 (Environmental Testing Equipment—Temperature Test Methods), IEC 61010-1:2010 (Safety Requirements for Electrical Equipment for Measurement, Control, and Laboratory Use), and meet CE marking requirements for electromagnetic compatibility (EMC Directive 2014/30/EU) and low voltage (LVD Directive 2014/35/EU). While not FDA 21 CFR Part 11–certified out-of-the-box, audit-ready documentation—including calibration certificates, maintenance logs, and IQ/OQ templates—is available upon request for GMP/GLP-regulated facilities.

Software & Data Management

The base configuration operates via front-panel keypad interface with non-volatile memory retention for last-used parameters. Optional RS-485 communication port enables integration into centralized lab management systems using Modbus RTU protocol. When paired with Yiheng’s optional LabLink software (Windows-compatible), users gain access to real-time temperature logging, trend graphing, alarm history export (CSV format), and electronic signature-enabled audit trails—supporting compliance with ISO/IEC 17025:2017 Clause 7.7 (Control of Equipment Records) and internal SOPs governing instrument qualification. All firmware updates are delivered via USB flash drive; no cloud dependency or internet connectivity is required.

Applications

• Enzyme kinetics assays requiring strict thermal consistency (e.g., amylase or protease activity at 37°C ±0.3°C)
• Calibration of liquid-in-glass thermometers, RTDs, and thermocouples against reference standards
• Pre-conditioning of polymer solutions prior to rheological testing (e.g., viscosity vs. temperature sweeps)
• Cell culture media warming and antibody diluent equilibration in molecular biology workflows
• Thermal stress testing of electronic components and solder joints using accelerated aging protocols
• Standardization of pH electrode response curves across multiple buffer temperatures
• Supporting ASTM D2196 (Rheology of Non-Newtonian Materials) and ISO 2555 (Viscosity Determination by Capillary Viscometer) test methods

FAQ

What is the maximum allowable load volume before temperature stability degrades?
Stability specifications (±0.3°C) are validated under empty-bath conditions per GB/T 5170.2. With full load (≥80% nominal capacity), expect ±0.5°C deviation—verified during factory IQ/OQ. We recommend maintaining ≥2 cm clearance between vessel bottom and tank floor.
Can the circulation pump be disabled for static bath operation?
Yes—pump activation is manually toggled via dedicated front-panel switch on all circulation-capable models (DK-8AXX, DK-8AD, etc.).
Is external temperature probe input supported?
Not natively. However, optional PT100 external sensor kits (YH-EXT-PT100) can be retrofitted with firmware v2.3+, enabling dual-sensor PID control (bath + sample location).
Do these units support dry-run protection?
No. They lack level sensors; operation without adequate fluid volume will trigger over-temperature alarm but may damage heater elements. Always confirm minimum fill line before startup.
What documentation accompanies shipment for regulatory audits?
Each unit ships with Factory Calibration Report (traceable to CNAS-accredited lab), Electrical Safety Test Certificate, and User Manual containing maintenance schedules, spare parts list, and troubleshooting matrix aligned with ISO 9001:2015 Annex A.7.