The utility model discloses a wide range ampere meter, this ampere meter include the current detection mutual -inductor of holding electrical connection with the high -voltage electrical equipment ground, have connect rectifier module and gauge outfit display module on the current detection mutual -inductor in proper order. The utility model discloses the high accuracy, current measurement's full flow precision is within 5%, passive, direct measurement need not other external condition, and adopts the energy storage mode to provide the action energy for the count module, and the place of use does not have the limitation, and it does not have the area of condition of power supply to use to have made things convenient for, because this patent does not have an internal resistance, this product has realized no internal resistance and has measured, does not have any influence to original circuit characteristic, and measuring range is big, range from 0A - 50A, the protection of machinery gauge outfit (gauge outfit display module) outrange, the action is protected in time rapidly, still useful pilot lamp reflects the state of equipment operation directly perceivedly.