The Great Wall HT-1500 Precision Temperature Control Unit
| Brand | The Great Wall |
|---|---|
| Origin | Henan, China |
| Manufacturer Type | Direct Manufacturer |
| Country of Origin | China |
| Model | HT-1500 |
| Cooling Method | Air-Cooled |
| Refrigerant | R410A |
| Temperature Control Mode | PID |
| Ambient Operating Conditions | 5–40°C / 30–70% RH |
| Setpoint Range | 5–40°C |
| Cooling Capacity | 1500 W |
| Temperature Stability | ±0.2°C |
| Circulation Pump Max Pressure | 0.14 MPa |
| Circulation Pump Max Flow Rate | 40 L/min |
| Reservoir Volume | 5 L |
| Heat Transfer Fluid Options | Deionized Water or 15% Ethylene Glycol Solution |
| Inlet/Outlet Port Size | Rc1/2 |
| Refill Pressure Range | 0.2–0.5 MPa |
| Refill Temp Range | 5–40°C |
| Refill Rate | 1 L/min |
| Refill Port Size | Rc3/8 |
| Overflow Port Size | Rc3/4 |
| Safety Protections | Overpressure, Overcurrent, Thermal Overload, Overheat, Low-Level Liquid Detection |
| Total Power Consumption | 1160 W |
| Input Current | 6.2 A |
| Power Supply | 220–240 V~, 50 Hz |
| Dimensions (W×D×H) | 403×576×645 mm |
| Noise Level | 68 dB(A) @ 1 m (front, no load, steady state) |
| Net Weight | 50 kg |
| Communication Interfaces | RS485, RS232, ZigBee Wireless |
| Data Logging | Internal Auto-Storage + USB Export |
Overview
The Great Wall HT-1500 Precision Temperature Control Unit is an engineered thermal management system designed for stable, continuous external cooling of sensitive laboratory and industrial equipment. It operates on a closed-loop refrigeration cycle using R410A refrigerant and employs air-cooled condensation to maintain precise temperature setpoints between 5°C and 40°C. Unlike simple chillers or immersion circulators, the HT-1500 integrates cascade PID control logic—simultaneously regulating expansion valve actuation, compressor staging, and fan speed—to achieve ±0.2°C temperature stability under dynamic load conditions. Its primary function is to deliver consistent thermal energy removal to external devices via a pressurized circulation loop carrying either deionized water or a 15% ethylene glycol/water mixture. This makes it suitable for applications requiring strict thermal boundary conditions, including analytical instrument cooling (e.g., HPLC column ovens, mass spectrometer sources), semiconductor process tool thermal stabilization, controlled-environment gas cabinet conditioning, and precision machining coolant regulation.
Key Features
- Cascade PID temperature control architecture with real-time modulation of refrigerant flow, compressor output, and airflow—ensuring high reproducibility across variable thermal loads.
- Integrated liquid level monitoring system with visual indicator and automated replenishment capability, maintaining optimal fluid volume without manual intervention.
- Dual-safety overflow and pressure-relief design compliant with IEC 61000-6-3 EMC and ISO 13849-1 functional safety principles for fluid containment integrity.
- Triple communication interface support (RS485, RS232, ZigBee wireless) enabling seamless integration into centralized facility monitoring systems or SCADA networks.
- Onboard data logging with timestamped thermal profiles, alarm events, and operational parameters; exportable via standard USB flash drive in CSV format for audit-ready traceability.
- Comprehensive protection suite including overpressure cutoff, thermal overload shutdown, phase-loss detection, low-level liquid interlock, and overtemperature lockout—meeting UL 61010-1 and GB 4793.1 safety requirements.
Sample Compatibility & Compliance
The HT-1500 is compatible with a wide range of heat transfer fluids, including deionized water and 15% ethylene glycol solutions—validated for use down to 5°C without freezing risk. Its Rc1/2 inlet/outlet ports conform to ISO 228-1 pipe thread standards, facilitating connection to standard laboratory tubing manifolds or OEM equipment interfaces. All electrical components comply with CE marking directives (EMC Directive 2014/30/EU, Low Voltage Directive 2014/35/EU) and meet RoHS 2011/65/EU material restrictions. The unit supports GLP/GMP-aligned operation through configurable data retention policies and tamper-evident logging protocols. While not FDA 21 CFR Part 11 certified out-of-the-box, its audit trail capabilities—including user-access logs, parameter change timestamps, and immutable USB exports—provide foundational infrastructure for regulated environments.
Software & Data Management
The HT-1500 features embedded firmware with non-volatile memory for storing up to 30 days of operational history at 1-minute intervals. Logged parameters include setpoint temperature, actual bath temperature, pump pressure, reservoir level, compressor runtime, and fault codes. Data export via USB adheres to ISO/IEC 17025 clause 7.7.1 requirements for raw data integrity. Optional Modbus RTU protocol implementation over RS485 allows bidirectional communication with third-party LabVantage, DeltaV, or custom Python-based control platforms. Firmware updates are performed via secure signed binary upload through the RS232 port, preserving configuration integrity during version transitions.
Applications
- Cooling of high-resolution mass spectrometry ion sources and detector housings to minimize thermal drift and improve signal-to-noise ratio.
- Thermal stabilization of photolithography alignment stages and laser interferometer enclosures in microfabrication cleanrooms.
- Temperature-controlled conditioning of specialty gas cabinets for ultra-high-purity (UHP) carrier gases used in CVD and ALD processes.
- Process-critical cooling of CNC machine spindles and hydraulic systems to mitigate thermal expansion-induced dimensional errors.
- Support of pharmaceutical stability chambers and bioreactor jacket circuits where ±0.2°C stability directly impacts kinetic assay fidelity.
- Integration with food-grade pasteurization validation rigs requiring traceable, repeatable cold-side thermal loading profiles.
FAQ
What heat transfer fluids are validated for use with the HT-1500?
Deionized water and 15% ethylene glycol/water mixtures are factory-validated. Propylene glycol or silicone oils are not supported due to viscosity and thermal conductivity constraints inherent to the pump and heat exchanger design.
Can the HT-1500 operate continuously at 5°C ambient temperature?
Yes, provided relative humidity remains below 70% and no condensation forms on internal components. Operation below 5°C ambient requires consultation with technical support to assess condensate management and refrigerant subcooling margins.
Is remote monitoring possible without physical cabling?
ZigBee wireless communication enables local network telemetry within a 10-meter line-of-sight radius. For enterprise-level integration, RS485 Modbus RTU is recommended for deterministic latency and noise immunity.
How does the auto-refill system prevent overfilling?
The system uses dual capacitive level sensors—one for minimum threshold activation and one for maximum cutoff—combined with a solenoid valve rated for 0.5 MPa max pressure. Refill halts immediately upon reaching the upper sensor threshold, independent of timer or flow duration.
Does the unit support NIST-traceable calibration?
While the HT-1500 includes a factory-calibrated PT100 sensor (±0.1°C accuracy at 25°C), end-user NIST-traceable recalibration requires third-party metrology services per ISO/IEC 17025. Calibration certificates are issued with each service event.
