CZGY HH-501 Precision Circulating Water Bath

Overview

The CZGY HH-501 Precision Circulating Water Bath is an engineered laboratory thermal management system designed for consistent, uniform temperature control in applications requiring stable liquid-phase heating environments. Operating on resistive heating and digitally regulated PID feedback control, the HH-501 maintains precise thermal conditions across its stainless steel bath chamber (400 × 300 × 180 mm) via a dual-mode circulation pump—enabling both internal recirculation for homogeneous bath temperature and external fluid transfer for jacketed reactor or condenser cooling/heating. Its operational range spans from ambient +5°C to 100°C, with a stability of ±0.5°C and 0.1°C digital resolution—making it suitable for routine procedures including solvent evaporation, sample pre-warming, enzymatic reaction incubation, distillation support, and calibration of temperature-sensitive probes. The unit complies with general electrical safety requirements per IEC 61010-1 for laboratory equipment and incorporates grounded chassis design, over-temperature protection, and dry-run prevention circuitry to ensure operational integrity under standard lab conditions.

Key Features

• Stainless steel inner tank (400 × 300 × 180 mm) resistant to corrosion and thermal fatigue
• Dual-mode circulation system supporting both internal homogenization and external fluid routing
• Digital PID temperature controller with SET key interface, adjustable P (proportional band), T (cycle time), and E (cut-off hysteresis) parameters
• High-resolution 0.1°C LED display with intuitive up/down arrow navigation for setpoint entry
• 1550 W heating capacity enabling rapid thermal ramping within specified stability limits
• Powder-coated cold-rolled steel housing for mechanical durability and chemical splash resistance
• Integrated ground-fault protection and automatic cut-off when water level falls below safe threshold

Sample Compatibility & Compliance

The HH-501 accommodates aqueous solutions, glycol-water mixtures, and low-viscosity organic solvents compatible with stainless steel and standard silicone tubing. It is not rated for oil-based media or aggressive halogenated solvents. While not certified to ISO/IEC 17025 or GLP-specific validation protocols out-of-the-box, its programmable PID architecture supports traceable parameter logging when integrated with external data acquisition systems. The device meets basic CE marking prerequisites for electromagnetic compatibility (EMC Directive 2014/30/EU) and low-voltage safety (LVD Directive 2014/35/EU), and adheres to laboratory best practices outlined in ASTM E29–23 (Standard Practice for Using Significant Digits in Test Data) for temperature reporting precision.

Software & Data Management

The HH-501 operates via embedded firmware without external software dependency. All configuration—including proportional band (P), cycle time (T), and hysteresis offset (E)—is accessible through the front-panel keypad after a 3-second SET button press. Default PID tuning values (I = 180 s, D = 45 s) are factory-set and non-user-adjustable; however, advanced users may optimize P and T for specific thermal loads to balance response speed and relay longevity. No built-in USB, RS-232, or Ethernet interface is provided. For regulatory environments requiring audit trails (e.g., FDA 21 CFR Part 11), third-party analog voltage output modules or external temperature loggers must be employed to capture time-stamped bath temperature data.

Applications

• Pre-conditioning of reagents and standards prior to HPLC, GC, or spectrophotometric analysis
• Controlled evaporation of solvents during sample concentration workflows
• Thermal equilibration of viscometers, density meters, and refractometers
• Support heating for rotary evaporators, reflux condensers, and jacketed glass reactors
• Incubation of temperature-sensitive biological samples where active agitation is unnecessary
• Calibration verification of thermocouples, RTDs, and infrared thermometers against NIST-traceable references

FAQ

What is the minimum safe operating water level?
The bath must be filled to at least 50% of internal volume (≥10.8 L) before power-on to prevent heater element dry-firing and irreversible damage.
Can the HH-501 be used with external circulation loops?
Yes—the unit includes dedicated inlet/outlet ports and a high-flow circulation pump rated for continuous external loop operation with compatible tubing (ID ≥ 8 mm).
Is the temperature sensor calibrated to NIST standards?
The internal Pt100 sensor is factory-calibrated; however, end-users must perform periodic verification using a certified reference thermometer per ISO 17025 guidelines if required for quality assurance documentation.
Does the HH-501 support cooling functionality?
No—it is a heating-only system. For sub-ambient control, integration with an external chiller or use of a separate refrigerated circulator is necessary.
What maintenance is recommended for long-term reliability?
Monthly descaling with 5% citric acid solution is advised for hard water environments; annual inspection of pump seals and electrical grounding continuity is recommended per manufacturer service guidance.