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After receiving the heater, a few test runs were made to determine the operating conditions. The voltage at which the heater reaches a steady temperature of 800°C needed to be determined. The heater was connected to a device which can vary the voltage applied to the heater, called a Variac. The Variac was then plugged into the wall outlet for power. This will be the same setup used in operation. We began with the voltage at 50V and slowly increased the voltage until the temperature near the heater was 800 °C. It took about 45 minutes to reach this temperature. The temperature was kept steady using 90V. The results of this test not only told us how long it takes to reach operating temperature (45 minutes), but also what voltage to set the Variac (90V). To test the electrical connections, we used a battery in the place of what will be a fuel cell. Batteries are similar to fuel cells in that they convert chemical energy to electrical energy, operate at solid state, and put out approximately the same amount of power. Our circuit was hooked up to a battery and successfully received data on the battery's electrical output. Safety is of great concern due to the use of hydrogen gas operating at high temperature. Therefore, there must be no interaction between the hydrogen gas and oxygen anywhere the temperatures are high (mainly inside of the fuel cell housing unit). To make sure that there are no leaks in our gas delivery system, we first ran helium through the system. Helium was used because of its small molecular size; if there are no helium leaks then we can be sure the bigger sized elements hydrogen and oxygen will not be able to diffuse through the housing. The test run with helium was done at the National High Field Magnetic Laboratory. Helium was run through the system at the same flow rate that will be used during normal operation (5 cubic feet/hr). A helium sensor was used to check for any leaks within the system. We suggest that before every use, a helium test is performed to check for leaks.
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