CZGY GY-DFY-55 Low-Temperature Constant-Temperature Circulating Bath
| Brand | CZGY |
|---|---|
| Origin | Jiangsu, China |
| Manufacturer Type | Direct Manufacturer |
| Product Category | Domestic |
| Model | GY-DFY-55 |
| Instrument Type | Constant-Temperature Bath |
| Circulation Mode | Internal & External Dual Circulation |
| Temperature Control | Refrigeration & Heating Combined |
| Bath Capacity | 55.5 L |
| Temperature Range | −5 °C to 100 °C |
| Temperature Stability | ±0.5 °C |
| Temperature Resolution | 0.1 °C |
| Power Supply | 220 V, 50 Hz |
| Inner Tank Dimensions | 500 × 370 × 300 mm |
| Heating Power | 4500 W |
| Compressor Power | 735 W (Danfoss) |
| Sensor | PT100 Class A, 4-Wire Solid-State Output |
| Construction Material | 304 Stainless Steel (Inner Tank & Outer Shell) |
Overview
The CZGY GY-DFY-55 Low-Temperature Constant-Temperature Circulating Bath is an engineered thermal management system designed for precise, stable temperature control across a broad operational range (−5 °C to 100 °C). It operates on the principle of dual-mode thermoregulation—integrating high-efficiency refrigeration (via a Danfoss rotary compressor) with robust resistive heating—to maintain setpoint accuracy under dynamic load conditions. Unlike single-function water baths, this unit supports both internal temperature uniformity within its 55.5 L stainless-steel bath chamber and external heat exchange via a pressure-rated dual-circulation pump system. Its architecture conforms to standard laboratory infrastructure requirements, delivering consistent thermal performance for applications demanding long-duration stability, such as reaction calorimetry, solvent reflux, enzymatic incubation, and cold-trap conditioning in vacuum systems.
Key Features
- Full-range dual-mode temperature control (−5 °C to 100 °C) with ±0.5 °C stability at setpoint and 0.1 °C digital resolution
- Dual-circulation capability: simultaneous internal recirculation (for bath homogeneity) and external fluid delivery (for jacketed reactors, condensers, or auxiliary equipment)
- Corrosion-resistant 304 stainless-steel construction for both inner tank and outer housing—suitable for aqueous, ethylene glycol, and silicone oil media
- High-fidelity temperature sensing using a Class A PT100 four-wire resistance thermometer with solid-state output for minimized self-heating and lead-wire compensation
- Industrial-grade Danfoss compressor (735 W) paired with 4500 W heating capacity to ensure rapid thermal ramping and recovery after load perturbation
- Intelligent LCD controller with programmable setpoint retention, over-temperature alarm, and compressor delay protection
Sample Compatibility & Compliance
The GY-DFY-55 accommodates standard laboratory glassware up to 500 mm × 370 mm footprint and 300 mm immersion depth. Its open-bath design permits direct placement of flasks, reactors, and condenser assemblies. The unit is compatible with common heat-transfer fluids—including deionized water, 30% ethylene glycol/water mixtures, and low-viscosity silicone oils—enabling operation below 0 °C without freezing risk. While not certified to UL/CSA or CE for standalone medical use, its electrical design complies with IEC 61010-1:2010 safety standards for laboratory equipment. All materials meet RoHS Directive 2011/65/EU restrictions on hazardous substances. For GLP/GMP environments, the device supports manual logbook documentation; optional RS232/RS485 interface enables integration into validated data acquisition workflows compliant with FDA 21 CFR Part 11 when paired with qualified software.
Software & Data Management
The GY-DFY-55 operates via embedded firmware with local front-panel control only—no proprietary PC software is bundled. However, its analog voltage output (0–5 V or 4–20 mA, configurable) and digital communication ports (RS232/RS485, optional) allow integration with third-party SCADA systems, LabVIEW, or custom Python-based logging platforms. Temperature data can be sampled at 1 Hz resolution and archived with timestamping. Audit trails require external configuration but are achievable using ISO/IEC 17025-aligned data capture protocols. Firmware updates are performed via USB port using manufacturer-provided binaries, with version history logged in non-volatile memory.
Applications
- Controlled-temperature synthesis in jacketed reactors (e.g., Grignard reactions requiring sub-zero initiation)
- Calibration of thermocouples, RTDs, and infrared sensors against NIST-traceable reference standards
- Stability testing of pharmaceutical formulations under ICH Q1A(R3)-defined storage conditions
- Viscometer and rheometer bath support for ASTM D445 and ISO 3104 viscosity measurements
- Cold trapping in rotary evaporation systems to prevent solvent vapor backstreaming
- Pre-conditioning of polymer samples prior to DSC or TGA analysis per ASTM E1356
FAQ
What heat-transfer fluids are recommended for operation below 0 °C?
For sustained operation between −5 °C and 0 °C, a 30% (v/v) ethylene glycol–deionized water mixture is recommended. Silicone oils (e.g., Dow Corning 200 Fluid, 50 cSt) may be used for extended high-temperature stability above 80 °C.
Is external circulation flow rate adjustable?
Yes—the integrated dual-head centrifugal pump offers stepless flow regulation from 0 to 25 L/min, with pressure capability up to 0.3 MPa at zero flow.
Does the unit include over-temperature or low-level protection?
Yes: hardware-based dry-run detection disables heating if liquid level falls below 30% capacity; independent thermal cutoff interrupts power at 110 °C.
Can the bath be operated in a fume hood?
Yes—its sealed refrigerant circuit and 304 stainless-steel enclosure meet standard fume hood compatibility requirements; ventilation clearance of ≥150 mm at rear and top is advised.
What maintenance intervals are recommended for the Danfoss compressor?
Under continuous operation, annual inspection of refrigerant charge and condenser coil cleaning is advised. No scheduled oil changes are required—the compressor uses sealed-for-life lubrication.
