Patent ID: 7284426

Claim:
A measurement apparatus of measuring fuel cell capacity used in fuel cell system comprising: a sensor device further comprising a multi-stage type first electrode set and a multi-stage type second electrode set, being accommodated into a fuel storage and/or a fuel flow layer to detect anode fuel capacity of the fuel storage and/or the fuel flow layer, said second electrode set being electrically connected to a low potential, wherein said first electrode set provides at least a first low limit electrode, a first middle electrode and a first high electrode and said second electrode set provides at least a second low limit electrode, a second middle electrode and a second high electrode corresponding to said first low limit electrode, said first middle electrode and said first high electrode respectively; at least three resistors each providing a first terminal being electrically connected to one of said first electrodes, and a second terminal being electrically connected to a high potential; an A/D converter providing input terminals being electrically connected to said first electrodes and the first terminal of the respective resistor to input analog measurement voltages and converts into corresponding digital measurement voltages; and a controller electrically connecting with the A/D converter to input the digital measurement voltages and converting the digital measurement voltages into liquid level of the anode fuel in the fuel storage and/or fuel flow layer. whereby, once liquid level of the anode fuel is detected by said low electrodes, insufficient amount of anode fuel is made up immediately; once liquid level of the anode fuel is detected by said middle electrodes, the liquid level is in a normal state; and once the liquid level of the anode fuel is detected by said high electrodes, filling the anode fuel is stopped immediately.