Heating-Cooling System
This unit has been designed to control the temperature of the measuring table in the range from about 0°C up to about 60°C. This is done by supplying electrical current to set of four Peltier elements having total maximum rated power up to 960 W. The elements have been attached to the rear side of the brass measuring table. Depending on the direction of the current flowing through Peltier elements the table may be either heated or cooled and the value of current (electrical power) determines the rate of the temperature changes. In case when the measuring table is cooled down the „hot” side of the Peltier elements must be intensively cooled down to prevent their overheating. This is provided by the system of the forced water flow. The water is cooled down in the external cooler supported by highly efficient fans. All these components, together with water container have been mounted inside a single unit called Cooling-Heating Controller. The unit has been designed to operate in either of two following modes:
- manual - standalone, simple control with the use of the knob on the front panel;
- remote - full control of the device operation from the computer via USB interface, through Solar Cells I-V Curve Tracer software,
- mixed mode.
In the manual mode the user chooses himself whether the measuring table is to be heated or cooled and controls the amount of electrical power supplied to Peltier elements. In temperature stabilization mode the unit self controls the heating, cooling and level of power to maintain the temperature set by the user.
View of the cooling-heating unit; inside the unit both container with water as well as highly efficient cooler for conditioning Peltier cells attached to the backside of the measuring table have been placed.
Features
- operation in temperature stabilization mode or continuous cooling or heating mode;
- DC output current instead of PWM current used;
- programmable temperature or power set point via PC or manually;
- control mode selectable and configurable by the user;
- infinitely variable regulation of temperature and power settings;
- temperature stabilization system with an accuracy of not less than 1.0%;
- integrated 1.3" OLED display on the front panel;
- simple control with the use of the knob on the front panel;
- full control of the device operation from the external system (computer) via USB interface;
- continuous temperature reading with a 0.01°C measurement resolution.
General Technical Specification
| Phase | Single Phase |
| Type | H-CC-04 |
| Supply voltage | 220-240 VAC 50/60 Hz |
| Power consumption | up to 1000 VA |
| Control modes | PID, heating, cooling |
| Operation modes | stand alone, remotely controlled via USB interface |
| Display | 1.3" OLED (128x64) |
| Table temperature adjustment range | 0°C - 60°C |
| Temperature measurement range |
-5°C - 65°C |
| Temperature probe input | PT100 |
| Output current | ±0 - 20 A (no PWM, bipolar) |
| Output voltage | up to 48 V (higher voltage on request) |
| Setpoint resolution |
0.1°C or 1% |
| Display resolution | 0.01°C |
| Measurement accuracy | 0.5% |
| Operating temperature | +10°C to +30°C (50°F to 86°F) |
| Operating humidity | 20-95% not condensing |
| Chassis | 19" 4U industrial rack-mount |
| Dimesions (H×W×D) | 483 x 178 x 353 mm; 19” x 7” x 13.9” (with front panel) |
| Case color | Black |
| Weight | ~7 kg ( ~ 15.4 lbs) |
Rear view of the heating-cooling unit.
In order to prevent overheating of the Peltier elements in the cover of water container a sensor of the actual coolant level (or liquid flow sensor) has been mounted. In case when the amount of water in the container due to some reasons (e.g. leaking out or evaporating after some time of use) decreases to the level which does not allow for effective cooling of the „hot” side of the Peltier elements during cooling down process of the measuring table, the ouptut power is switched off. In such case neither stabilization, cooling nor heating of the measuring table is possible before refilling the water container to the level which will allow to switch again the electrical power to Peltier elements.
View of top of the full H-bridge mounted in the cooling-heating unit (at the bottom side are visible high-current terminals).
