| 摘要 |
<p>A test control circuitry conducts an electrical current through a thermo electric cooler (62) for the purpose of testing the operability of a thermal control unit (60). At temperatures higher than a temperature threshold, this electrical current is directed such that the thermo electric cooler cools a temperature sensitive switch (68). The direction of the electrical current is inverted at temperatures lower than such temperature, causing heat to flow to the temperature sensitive switch. These specified temperatures of the test control circuitry are programmable either manually or automatically from a remote computer linked to the control circuitry. Optionally, a temperature sensor such as a thermo-couple or thermistor and their associated electrical circuitry is used as temperature sensitive switch. In such cases its temperature threshold is programmable.</p> |
