Refers to the voltage "Micro Cooling Fan" work properly when the relay coil is needed, which is controlled by the control voltage of the circuit. The relay of the model, may be an alternating voltage or a DC voltage. DC resistance is the DC resistance of the relay coil, can multi meter measurements. "Micro Cooling Fan" pull current relay means capable of producing a minimum current pull action. In normal use, given the current must be slightly larger than the pull current, this relay can stably. For coil applied voltage, usually not more than 1.5 times the rated working voltage, otherwise it will have a greater current to the coil burnt. "Micro Cooling Fan" discharge current is the relay produced the maximum current release action. When the current relay state is reduced to a certain extent, the relay will be released back to the non-energized state. Then the current is much smaller than the pull current.