The utility model relates to a test device, include gaseous collection system, electrically conductive and conducting rod, electrically conductive is equipped with the chamber that holds that is used for bearing coke and test solution, and the one end of conducting rod is inserted and is held the intracavity, and the other end is connected with gaseous collection system, inserts supply circuit between electrically conductive piece and the conducting rod, and supply circuit is equipped with the power and is used for the voltage current measuring device of the measuring circuit voltage curent change. Before the test, fill the coke in holding the intracavity to pour test solution into, during the test, start supply circuit, change rule through the moisture coke of voltage current measuring device record voltage electric current under the different power -on time turns into resistivity change rule to passing through gases collection system collects produces gas, after the test is accomplished, obtain the change of conducting rod quality to coke resistance changes and the gaseous volume of collection determines whether there is the air -resistor effect through measuring, measures the product gas characteristic of moisture coke in power -on process.