SMC HEF Series Peltier-type Chillers
Thermo-con/Compact Type, Air-cooled
Key Features
- Precise Temperature Control: Utilizes a Peltier device for accurate temperature management of circulating fluids.
- Refrigerant-Free: Environmentally friendly design without refrigerants.
- Low-Noise Design: Operates at a low noise level of 37 dB (at low load), with options to further reduce noise.
- Compact Size: Dimensions of 130 mm (Width) x 210 mm (Height) x 150 mm (Depth).
- Fast Response: Achieves an 86% reduction in temperature change time (e.g., 41 seconds to lower temperature by 10°C compared to previous models).
- Easy Maintenance: Features an easily accessible and replaceable dustproof filter.
The unit is depicted with its main components labeled: Display/Operation panel, Circulating fluid level gauge, and a replaceable Dustproof filter.
Performance Highlights
- Cooling Capacity: 220 W (Tap water, 1 L/min flow rate, 25°C ambient, 25°C fluid).
- Heating Capacity: 500 W (Tap water, 1 L/min flow rate, 25°C ambient, 25°C fluid).
- Temperature Stability: ±0.1°C.
- Set Temperature Range: 10°C to 60°C.
Construction and Principles
The thermo-con unit employs a Peltier element (thermo-module) situated between a heat exchanger and a heat sink. This setup, controlled by DC power supply, precisely regulates the circulating fluid's outlet temperature. The circulating fluid is drawn from a tank, pumped through heat exchangers and a temperature sensor, and then returned to the tank. Air for heat dissipation is drawn from the front and expelled from the rear.
A schematic diagram (Figure 1) illustrates the internal components: Controller, Power switch, Power supply, Peltier device, Heat exchanger, Heat sink, Temperature sensor, Fan, Tank, Pump, and fluid ports (OUT, IN, Fill port). Figure 2 shows the air flow direction, entering the front and exiting the rear.
Application Examples
The HEF Series chillers are versatile and suitable for various applications, including:
- Cooling Diode Lasers
- Cooling Optical Cameras (compatible with digital cameras)
- Microscope Cooling Plates
- Laser Oscillators
- Cooling Power Devices
- Beam Bumpers
- Cooling Glass Heat Exchangers
- Circulation Between Gas Generation Analyzers and Jacketed Vessels
- Cooling Sample Embedding Machines
Diagrams illustrate the chiller connected to each of these applications, showing the fluid circulation paths.
Specifications
| Feature | Specification |
|---|---|
| Cooling Method | Thermoelectric device (Thermo-module) |
| Radiating Method | Forced air cooling |
| Control Method | Cooling/Heating automatic shift PID control |
| Ambient Temperature/Humidity | 10 to 35°C, 35 to 70% RH (No condensation) |
| Circulating Fluid | Tap water, Ethylene glycol aqueous solution (20% or less) |
| Set Temperature Range | 10.0 to 60.0 °C (No condensation) |
| Cooling Capacity | 220 W (Tap water)*¹ |
| Heating Capacity | 500 W (Tap water)*¹ |
| Temperature Stability | ±0.1°C*² |
| Pump Capacity | Refer to performance charts. Approx. 110 mL tank capacity. |
| Port Size | Rc1/4 |
| Fluid Contact Material | Stainless steel, EPDM, NBR, Ceramics, PPE, PPS, Carbon, PP, POM |
| Power Supply | 24 VDC ±10% |
| Power Consumption | 12.5 A (Peak current 18 A) |
| Alarm | Refer to "Alarm" section. |
| Communications | RS-232C/RS-485 |
| Weight | Approx. 3.5 kg |
| Noise Level | 37 to 60 dBA (45 dBA: When set to constant fan speed mode)*⁴ |
*¹ Conditions: Set temperature 25°C, Ambient temperature 25°C, Circulating fluid flow rate 1 L/min. For options, refer to performance charts.
*² Indicated values are for stable load without turbulence. May vary based on operating conditions.
*⁴ Noise can be suppressed to 45 dBA or less by setting to constant fan speed mode, but this reduces cooling capacity.
Cooling Capacity Calculation Example
The document provides an example for calculating cooling capacity:
Formula: Q = (ΔT × V × ρ × C) / (h × 60 × 1000)
Where:
- Q = Cooling capacity (W)
- ΔT = Temperature difference (K or °C)
- V = Volume (L)
- ρ = Density (kg/m³)
- C = Specific heat (J/(kg·K))
- h = Time (min)
Example Calculation: Cooling 2 L of tap water by 10°C in 15 minutes (from 30°C to 20°C).
Using typical values for tap water (ρ = 1 x 10³ kg/m³, C = 4.2 x 10³ J/(kg·K)):
Q = (10 × 2 × 1 × 10³ × 4.2 × 10³) / (15 × 60 × 1000) = 93.3 W
With a 20% safety factor, the cooling capacity is 112 W.
Typical physical property values for Ethylene Glycol Solution (20%) and Water are provided in tables for various temperatures.
Dimensions and Connectors
The unit has compact dimensions: 130 mm (W) x 210 mm (H) x 150 mm (D). Key ports include a fluid fill port, circulating fluid OUT (Rc1/4), and circulating fluid IN (drain) (Rc1/4). The front panel houses the display/operation panel and level gauge. The rear or side typically contains the dustproof filter and air vents.
Detailed dimension drawings show the placement of ports, panels, and mounting points. Connector details are provided for the Power connector (24 VDC) and a multi-pin Communication connector (supporting RS-485, RS-232C, RUN/STOP signals, and alarm output).
Power Cable Accessory: Available for single-phase 100/115 VAC and 200 VAC types.
Operation Display Panel and Alarms
The display panel shows the current temperature (PV) and set temperature (SV). Indicator lights show RUN status and ALARM status. Control keys (RUN/STOP, MODE, UP, DOWN) are available for operation.
The unit supports eight types of alarm codes, which can be read via serial communication or indicated on the display. Common alarms include:
- AL0: Memory error
- AL1: Controller error
- AL2: Temperature sensor disconnection
- AL3: Temperature sensor short circuit
- AL4: Temperature sensor high temp error
- AL5: Temperature sensor low temp error
- AL6: Low fluid level alarm
- AL7: Thermostat alarm (e.g., due to clogged heat sink or fan/pump failure)
Alarms typically result in the unit stopping operation.
Maintenance
On-site maintenance is generally not conducted by SMC. Repairs typically require returning the unit to an SMC service site.
Regular inspections (monthly) are recommended, including checking displayed contents, unit temperature/vibration/sounds, power supply, circulating fluid condition, and radiated air flow.
Options
High-Pressure Pump Mounted (Option P): Available for customers with higher piping resistance. Note that this option may reduce cooling capacity by approximately 20 W due to heat generation from the pump.
* Options must be selected when ordering; they cannot be added later.
Optional Accessories
- AC Adapter: Model HEC-S1896, provides 24 VDC output.
- Power Supply Cable: Available for 100/115 VAC (HRS-CA001) and 200 VAC (HRS-CA002) types.
- Dustproof Filter: Part numbers HEF-FL001 (set) and HEF-FL002 (filter only).
Specific Product Precautions
Users are advised to read the handling precautions and operation manual thoroughly. Key precautions include:
- Handling: Avoid strong vibration/impact. Handle as a heavy object. Mount on a flat, level surface.
- Operating Environment: Keep within specified temperature/humidity. Avoid clean room usage as the unit generates dust. Protect from low molecular siloxanes.
- Radiation Air: Ensure air inlets/outlets are not obstructed or exposed to dust. Consider airflow arrangement when using multiple units. Clean the built-in filter periodically.
- Circulating Fluid: Use specified fluids (tap water, ethylene glycol solution up to 20%). Deionized water may lose conductivity and promote bacterial growth. Avoid fluids with metal powders. Never operate without circulating fluid. Ensure proper piping to avoid negative pressure. If using tap water, adhere to quality standards to prevent corrosion and scale.
- Maintenance: Prevention of electric shock and fire is critical. Cut off power immediately in case of abnormal sound, smoke, or odor.
Tap Water Quality Standards: A table lists recommended quality standards for tap water used as circulating fluid, covering pH, electric conductivity, ion content, hardness, and silica, to minimize corrosion and scale generation.
